Re: Assembler Question
In a message dated 2/10/2009 11:25:27 P.M. Central Standard Time, cfmpub...@ns.sympatico.ca writes: (BUNCH - Burroughs Univac Ncr Cdc Honeywell -- if I remember correctly). I thought that the C in BUNCH was Compagnie des Machines Bull. CDC made mainframe-compatible disk drives, though, I think, but not central processors. Bill Fairchild Rocket Software **The year's hottest artists on the red carpet at the Grammy Awards. AOL Music takes you there. (http://music.aol.com/grammys?ncid=emlcntusmusi0002) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Interesting APAR OA27291 an undocumented change to GETMAIN Behavior in z/...
In a message dated 2/5/2009 12:04:24 P.M. Central Standard Time, dennis.ro...@lmco.com writes: I had always been taught that the ONLY time storage is cleared is when RSM assigns a real page to a virtual page that is not already backed by one in aux storage. And how is a programmer supposed to know that this has happened? Ergo, always initialize. Bill Fairchild Rocket Software **Stay up to date on the latest news - from sports scores to stocks and so much more. (http://aol.com?ncid=emlcntaolcom0022) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Auditors
In a message dated 1/7/2009 1:07:55 P.M. Central Standard Time, howard.bra...@cusys.edu writes: And there's always the competition betwen liberal and conservative. Does anyone really understand those terms? I doubt it.Heck, I don't understand the difference between liberal and conservative.At least when I look at what the next US president proposes and compare it to what the previous president proposed, I don't see their values are significantly different. Historically, there was a difference. Look up both terms in some reference work. Today there is no difference. The two labels today are used to divide and conquer the voting public. This process is known as a Hegelian dialectic. Look that one up, too. Now that that's over, I trust this thread will get back to IBM Mainframes. Bill Fairchild Rocket Software **A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/10075x1215047751x1200957972/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072%26hmpgID=62%26bcd=De cemailfooterNO62) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Find TCB address from SRB
In a message dated 12/17/2008 12:30:45 P.M. Central Standard Time, edja...@phoenixsoftware.com writes: What if you were scheduled by another SRB? A global SRB can also be scheduled during the processing of an I/O interrupt, in which case there could be neither a current TCB nor a current SRB. Bill Fairchild Rocket Software **A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/10075x1215047751x1200957972/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072%26hmpgID=62%26bcd=De cemailfooterNO62) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Got burned by the FORCE COMMAND ?
In a message dated 12/4/2008 4:37:18 P.M. Central Standard Time, [EMAIL PROTECTED] writes: But I do agree that a appearance of hung can be, for example, the closing of many, many open files. I once canceled a job step with about 1,000 active subtasks, a job step with the maximum allowable number of DD statements (about 1,700 at the time), and a program that was nothing but an SVC 12 (which caused an infinite loop of creating SVRBs). In each case, it took 10 or 15 minutes for the cancel function to complete normally. I probably added the DUMP option on all those CANCELs. The Large System Effect will get you every time you mess around with a huge number or amount of resources. Bill Fairchild Rocket Software **Make your life easier with all your friends, email, and favorite sites in one place. Try it now. (http://www.aol.com/?optin=new-dpicid=aolcom40vanityncid=emlcntaolcom0010) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Big sorts
In a message dated 12/1/2008 10:26:13 A.M. Central Standard Time, [EMAIL PROTECTED] writes: I had never previously seen the term Shannon, defined to mean 1 mole of bits (6.02 x 10^23 bits). Since the title of the linked article includes the word Information, I would assume that Shannon refers to the late Claude Elwood Shannon, who did seminal research and published papers on Information Theory. _http://en.wikipedia.org/wiki/Claude_Shannon_ (http://en.wikipedia.org/wiki/Claude_Shannon) Bill Fairchild Rocket Software **Finally, one site has it all: your friends, your email, your favorite sites. Try the NEW AOL.com. (http://www.aol.com/?optin=new-dpicid=aolcom40vanityncid=emlcntaolcom0006) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: CPU time/instruction table
In a message dated 12/1/2008 11:53:31 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Thank you very much, I will try to messure There is a wealth of info on this topic already on the Archives, q.v. Discussions range from why it is no longer meaningful to some serious benchmark results. Bill Fairchild Rocket Software **Finally, one site has it all: your friends, your email, your favorite sites. Try the NEW AOL.com. (http://www.aol.com/?optin=new-dpicid=aolcom40vanityncid=emlcntaolcom0006) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Online volume mystery
In a message dated 11/25/2008 7:57:03 A.M. Central Standard Time, [EMAIL PROTECTED] writes: UNIT TYPE STATUS 9090 3390 O-RAL RAL, as it turns out, means 'restricted to allocation', which I've never seen before. I'm still looking, but currently stumped as to how it managed to get into this state. Anybody have any ideas? Try getting a hexadecimal dump of at least the UCB and DCE with the operator command DEVSERV. Then post that for us control block maniacs to look over. Bill Fairchild Rocket Software **Check out smokin’ hot deals on laptops, desktops and more from Dell. Shop Deals (http://pr.atwola.com/promoclk/10075x1213345834x1200842686/aol?redir=http://ad.doubleclick.net/clk;209513277;31396581;l) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Startio Question
In a message dated 11/21/2008 5:40:02 P.M. Central Standard Time, [EMAIL PROTECTED] writes: How would one via z/OS software make z/OS think that there is an I/O device attached to a particular channel? The way z/OS itself attaches a device to a particular channel is with the Modify Subchannel (MSCH) instruction. This instruction causes a real link to be built between a device-unique control block in the Hardware Storage Area (HSA) and a channel path-unique control block in the HSA. However, this requires that both the device and channel path be real. Gerhard's answer reminded me of what VM does. It controls real devices and real channel paths. It intercepts all privileged instructions. When a guest machine is IPLed under control of VM, VM intercepts all the instructions that the guest machine is doing to initialize its use of devices and channels. VM simulates the way the MSCH instruction works. VM also intercepts all SSCHs that occur after the virtual IPL, and knows which real device corresponds to the virtual (guest) machine's virtual device. In other words, I run some software that makes z/OS think it is a device and then intercept all channel commands to that device. You cannot intercept channel commands (assuming you meant channel command words, or CCWs). CCWs are processed partly by the channel subsystem, partly by the control unit, and do not involve machine instructions (like LA, MVC, etc.). In fact, a channel program is called a channel program because it consists of a series of I/O device instructions (really I/O control unit instructions) that are being executed in series with tests and branch on condition kinds of instructions at various points in the channel program, which runs separately from and simultaneously with software programs. Software consists of a series of machine instructions that are all documented in the Principles of Operation. The only way I can see to do what you say here is to build software that intercepts all machine instructions that could possibly operate on a device (SSCH, HSCH, CSCH, MSCH, etc.) or a channel path, then scan the channel program (if the instruction involves a channel program), and simulate the action of the instruction, channel subsystem, channel path, controller, and device. This is quite difficult. One example of commercially available software that does this is Virtual Tape (sorry, I don't know the exact product name or vendor anymore; it was developed originally in an EMC development lab in Tel Aviv). It intercepts all I/O requests involving tape devices, treats the tape device involved as virtual, scans the channel programs, simulates what they would do with a real tape by using a real DASD instead to write the data to (if a tape write CCW is being simulated) or from which to read the data (if simulating a tape read CCW), then manipulates the application's control blocks to make the application think that the I/O worked just as it would have with a real tape controller and device. So far everything I see in the z Arch Pop tells me how to communicate to a device, but not how to be a device. Would someone please give a hint where to look? I am not sure I understood your question, so I doubt that the above answers your question. And doing what I described is not easy. Bill Fairchild Rocket Software **Check out smokin’ hot deals on laptops, desktops and more from Dell. Shop Deals (http://pr.atwola.com/promoclk/10075x1213345834x1200842686/aol?redir=http://ad.doubleclick.net/clk;209513277;31396581;l) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Startio Question
In a message dated 11/21/2008 6:24:02 P.M. Central Standard Time, [EMAIL PROTECTED] writes: Well, this was one of the first IBM related things that popped up in Google: _http://www.freepatentsonline.com/6453277.html_ (http://www.freepatentsonline.com/6453277.html) Be careful when reading through the text of a patent application. There are certain words that are used inside patent applications that are there for ancient, historical, and legal reasons and do not necessarily relate exactly to the real world of computers as we know them. I suspect that one reason for the arcane terminology in patent applications is to obfuscate the explanation. Plurality is a good example of such obfuscatory and archaic words. A method and system of emulating an input/output (I/O) device in a mainframe environment. A started task executing as part of the operating system gains control of I/O instructions directed to virtual devices by insuring that such I/O instructions cause interrupts. The fact that the started task gains control of I/O instructions directed to a particular device is what makes that device virtual. If the started task weren't doing this, then the device would have to be real. The started task could also intercept instructions going to a real device and do things that would not affect the reality of the device; e.g., scan the channel program looking for character string XYZ being transferred to or from the device, and, if found, signal the operator, cancel the application, etc. One way for a started task to insure that such I/O instructions cause interrupts is to do what VM does; namely, force all software running on that processor to be in problem state. Then any privileged instructions will cause interrupts which this started task could then intercept. If the privileged instruction is not one of the 15 or so that operate on I/O hardware, then the started task does nothing special with the intercepted instruction (although it must allow the instruction to execute, or else perfectly simulate what it does). If the intercepted instruction is one of the I/O instructions, then the started task would presumably look at the device involved. If the device is one that the started task wants to treat as virtual, then the STC must do something special. Otherwise it allows the I/O instruction to execute normally (either allow it to execute or else perfectly simulate it). After having read part of the patent application you mentioned, I see a much simpler way to cause an interrupt when an SSCH or TSCH is executed against one particular device, which is to change what's in the UCB field containing the subchannel number in such a way that the subchannel number is invalid, and then a program interrupt will occur when any I/O instruction (SSCH, TSCH, MSCH, etc.) which has to specify a subchannel number as one of its operands is executed. The STC would have to replace the program interrupt new PSW's instruction address, so that all program interrupts go into the STC, which then examines the type of program interrupt, particular machine instruction involved, etc. According to what this patent says, its software is not intercepting channel commands (CCWs), but is intercepting machine instructions (SSCH, e.g.) that are being executed against a particular device which the software wants to treat as virtual. The started task then hooks the branch point for such interrupts. This means it replaces the instruction address part of the I/O interrupt new PSW so that an I/O interrupt will take you immediately into the STC rather than into IOS. Then the STC has to make sure that no matter what the STC does, the status of the system will be restored as it was when the I/O interrupt occurred, and then it when the STC ends all its processing it must branch to the location that was originally in the I/O interrupt new PSW. Upon obtaining control, the started task causes the I/O source to believe a transaction with a predefined data space in a general storage area on board the mainframe is actually a transaction with a physical device. Upon obtaining control, an STC can do whatever it likes with the device against which the intercepted instructions were being executed. Which led to the actual patent here: _http://www.patentstorm.us/patents/6453277/fulltext.html_ (http://www.patentstorm.us/patents/6453277/fulltext.html) How this can be a patent I don't understand. I thought patents were for inventions, and copyrights were for software. Bill Fairchild Rocket Software **Check out smokin’ hot deals on laptops, desktops and more from Dell. Shop Deals (http://pr.atwola.com/promoclk/10075x1213345834x1200842686/aol?redir=http://ad.doubleclick.net/clk;209513277;31396581;l) -- For IBM-MAIN subscribe / signoff /
Re: Startio Question
In a message dated 11/21/2008 6:26:45 P.M. Central Standard Time, [EMAIL PROTECTED] writes: and after looking at the S/370 books I see the SIO x'9C' instruction which made me think about STARTIO again. On a S/370, the machine instruction SIO (x'9C') was named Start I/O. It was a single machine instruction what told the channel subsystem to start processing a given channel program (series of CCWs). Ever since S/370-XA in the early 1980s, there is no more SIO instruction. There is now the machine instruction SSCH, named Start Subchannel. It functions very similarly to SIO, namely it tells the channel subsystem to start processing a given channel program. To confuse us all even more, IBM devised a macro spelled STARTIO (rhymes exactly with Start I/O, the name of the old SIO instruction). This macro requires as input the address of an IOSB. Look in SYS1.MODGEN (or maybe MACLIB) for IOSDIOSB or something like that for the DSECT of an IOSB. The macro makes sure the IOSB address is in general purpose register 1, then BALRs into an IOS module which builds a request control block structure that points to your IOSB, and puts this request on a queue of such I/O requests for the UCB involved. Sooner or later another IOS module is executed which removes this request from the queue and tries to start the I/O operation by using the SSCH instruction. Now I'm reading US Patent 6,453,277 which is Virtual I/O Emulator in a Mainframe Environment. Nowhere in this patent does it mention STARTIO. It talks about FLIH hooks instead. I would speculate that the patented software simply uses the STARTIO macro to do its I/O requests rather than a higher level access method macro, such as EXCP. So trying to research STARTIO in how this software works is a red herring. I have built much software that intercepts the IOS module that STARTIO BALRs into. This allows me to look at each channel program before it is started with the SSCH instruction way down deep inside another IOS module. But if you want to simulate every possible event involving an I/O device, then you may also need to intercept I/O interrupts. But a FLIH (First Level Interrupt Handler) could also be intercepted by forcing a UCB's Subchannel ID number to be invalid. Then any I/O instruction involving that device will cause a program interrupt. The patented software would then gain control over the I/O instruction by having also overlaid the program interrupt new PSW's instruction address. The location directly pointed to by any of the six new PSWs is called the First Level Interrupt Handler for that particular class of interrupts. The code to process an interrupt is typically quite voluminous, so the FLIH typically just saves system status somewhere and then branches to the much grander piece of code called the Second Level Interrupt Handler (SLIH),where all the real work is done for that type of interrupt. There are typically many ways to intercept certain events inside z/OS. Causing a program interrupt with an invalid SCHID and front-ending the program FLIH is just one of several ways to do it. There is much less overhead in this method than if you intercept all STARTIO macros and all I/O interrupts, since only I/O events occurring on one particular device will cause the intercept to occur. Bill Fairchild Rocket Software **Check out smokin’ hot deals on laptops, desktops and more from Dell. Shop Deals (http://pr.atwola.com/promoclk/10075x1213345834x1200842686/aol?redir=http://ad.doubleclick.net/clk;209513277;31396581;l) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Mainframe Jobs Considered Recession Proof
In a message dated 11/12/2008 9:03:50 P.M. Central Standard Time, [EMAIL PROTECTED] writes: Just what in the H*** is a Mainframe Computer Expert? Another example of a know-nothing with diarhea of the mouth and constipation of brains. Recession proof might be true for mainframe computer experts, whatever that means, but that does not imply that said jobs will be salary-decrease-proof. Bill Fairchild Franklin, TN “We can evade reality, but we cannot evade the consequences of evading reality.” [Ayn Rand] **Get movies delivered to your mailbox. One month free from blockbuster.com (http://pr.atwola.com/promoclk/10075x1212639737x1200784900/aol?redir=https://www.blockbuster.com/signup/y/reg/p.26978/r.email_footer) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Performance Question - Dynamic PAV
In a message dated 11/5/2008 11:36:58 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Since, I didn't keep any of this thread, I am going by memory. I think that's why God invented the archives. Check the archives for what each of you two said. Copy and paste exact quotes of one another. Then apologize to each other, or else continue to carry on your feud, PRIVATELY. PLEASE. Bill Fairchild Franklin, TN **AOL Search: Your one stop for directions, recipes and all other Holiday needs. Search Now. (http://pr.atwola.com/promoclk/10075x1212792382x1200798498/aol?redir=http://searchblog.aol.com/2008/11/04/happy-holidays-from -aol-search/?ncid=emlcntussear0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: z/Architecture Reference Summary
In a message dated 10/20/2008 1:48:33 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: The z/Architecture Principles of Operation, SA22-7832-06, is now $1434.96! I hope someone can correct those prices. Maybe they are in Yen. Or maybe IBM is pricing based on the expected value of one US dollar by the time they receive your order next week. Bill Fairchild Franklin, TN **BUY Indiana Jones and the Kingdom of the Crystal Skull on DVD today! (http://pr.atwola.com/promoclk/10075x1209326865x1200539441/aol?redir=http://www.indianajones.com/site/index.html) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Determining file attributes *before* OPEN
In a message dated 10/7/2008 12:02:05 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Thanks, but LOCATE/CAMLST only returns a volume list, not D(S)CB attributes. I can get the first few volumes from RDJFCB as well, along with the DSN, and that's enough info to use OBTAIN (which I missed the first time around) to get the DSCB. Get the DSN from the RDJFCB. Then get the volsers from either the RDJFCB or the data returned via LOCATE. Plug each volser into the CAMLST that you use with OBTAIN, then do the OBTAIN to read the DSCB for each volume. Or use the volser from the RDJFCB data. The only difference is which source (LOCATE or RDJFCB) will give you the complete volser list, if either. Bill Fairchild Rocket Software **New MapQuest Local shows what's happening at your destination. Dining, Movies, Events, News more. Try it out (http://local.mapquest.com/?ncid=emlcntnew0002) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: The Obsolete mainframe?
In a message dated 10/6/2008 4:50:00 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: David Alcock [EMAIL PROTECTED] 10/6/2008 4:32 PM Today's Dallas Morning News has an editorial written by their staff with the words could become as obsolete as computer mainframes. http://www.dallasnews.com/sharedcontent/dws/dn/opinion/editorials/stories/DN-t op10_06edi.State.Edition1.43fe5ef.html I plan to send them a friendly email to tell them that the mainframe is alive and well. ;-) Send them a friendly email stating what the Gartner Group's estimated total earnings from all mainframe hardware and software vendors were last year. Add suggest politely that mainframes are much less obsolete than is honest journalism. Bill Fairchild Rocket Software **New MapQuest Local shows what's happening at your destination. Dining, Movies, Events, News more. Try it out! (http://local.mapquest.com/?ncid=emlcntnew0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: VSAM I/O
In a message dated 10/5/2008 11:55:34 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I am looking for the simplest way to intercept/modify an i/o for a VSAM data set without impacting the application. I only know of one way to intercept/modify an I/O of any kind, and it is not simple. You must insert a front-end for an IOS module that is involved with the normal processing of an I/O request before it is started with the SSCH instruction. There are several different modules from which you could choose, but in all cases this is an extremely non-trivial task, your code that inserts the front-end must be authorized, and your code that runs when the I/O is intercepted must be bullet-proof with industrial-strength recovery. If you are not faint-hearted and have a sandbox system that you can crash at least 20 times, email me offline for further enlightenment. And intercepting the I/O is an order of magnitude easier than modifying it once intercepted. The reason that modifying it is so hard is because of the vast complexity of DASD channel programs, all possible variations of which your code must support. Bill Fairchild Rocket Software **New MapQuest Local shows what's happening at your destination. Dining, Movies, Events, News more. Try it out! (http://local.mapquest.com/?ncid=emlcntnew0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Mapping Macros for arguments to CCWs Define Extent, Locate Record etc.?
In a message dated 9/30/2008 11:35:38 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Anyone know where I can find mapping macros I could download/copy for the argument / parameters to Define Extent, Locate Record, etc.? Rather than type them up myself and make mistakes... John, I sort of remember finding both the DX and LR DSECTs about 20 years ago in SYS1.MACLIB or MODGEN. I can't find them now in either of those libraries. So I typed them up myself and made mistakes. :-( Many of the DX fields are in the DEB extension, so you could copy those fields' descriptions and that would be a good start. Then there's the Prefix command code's parameters that also need to be externalized, but that will probably never happen since that's all proprietary now. The Prefix parameters consist of all the DX parameters, some new DX fields, and all the parameters for the first LR or LRX in the chain after the DX. There are also many fields in the Prefix data that are not in either the DX or LR parameters. Bill Fairchild Rocket Software **Looking for simple solutions to your real-life financial challenges? Check out WalletPop for the latest news and information, tips and calculators. (http://www.walletpop.com/?NCID=emlcntuswall0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Mapping Macros for argument to CCWs Define Extent, Locate Record etc.?
John, Here is another reason why we z/OS-ers should be thankful for the VM world. Check out http://www.vm.ibm.com/pubs/cpdacb/index.html?where there is a whole passel of DSECTs.? You want to look at DEARG, LRARG, LRDA, and CDPFX.? And don't let IBM know that their VM developers have?public-domained [1]?a DSECT which I have been unable to get through official channels. Bill Fairchild [1] I just verbed the noun phrase public domain. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Mapping Macros for argument to CCWs Define Extent, Locate Record etc.?
I stand corrected on my verbing. Here is the update: ... don't let IBM know that their VM developers have generally-availabled [1] a DSECT which I have been unable to get through less than generally available, official channels. Bill Fairchild Rocket Software [1] I just verbed the adjectival phrase generally available. **Looking for simple solutions to your real-life financial challenges? Check out WalletPop for the latest news and information, tips and calculators. (http://www.walletpop.com/?NCID=emlcntuswall0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SRB Wait JWT
In a message dated 9/25/2008 10:53:46 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Though an SRB cannot issue a WAIT macro, Because an SRB cannot execute an SVC, which the WAIT macro does. it can go into a wait. In particular, the manual states that the SRB can use SUSPEND to stop itself. Some other process would then need to do a RESUME to restart it. Also a higher-priority function can interrupt a running SRB. Bill Fairchild Rocket Software **Looking for simple solutions to your real-life financial challenges? Check out WalletPop for the latest news and information, tips and calculators. (http://www.walletpop.com/?NCID=emlcntuswall0001) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: OT: Stretch article
From the article on Stretch: [Stretch] ... could perform 100 billion computations a day and handle half a million instructions per second. There are 86400 seconds in one day. Half a million instructions per second for one day equals 43 billion instructions, which somehow were able to perform 100 billion computations. I don't know of any z/OS instructions that can perform more than one computation per instruction, but I must confess I haven't read about all the newest ones yet. How was Stretch able to perform over two computations for each instruction handled? Bill Fairchild Rocket Software **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Hyper PAVs vs. Dynamic PAVs
In a message dated 9/12/2008 2:03:47 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Can anyone tell me what kind of improvements can be realized changing PAVs from Dynamic to Hyper? I'll leave the quantification to others and to your own mileage calculations. What is the real difference between the two? First came static PAVs. You decide where the PAVs are inside each LCU (Logical Control Unit), a collection of up to 256 devices. If you want to change any of them, you have to redo your configuration. Lots of work. Error-prone PITA. Hard to change. You must know your hot devices in advance. Next came dynamic PAV. The WLM decides within one LCU what should be PAVed for the next WLM interval in order to deliver your requested goals, WLM issues control I/O commands to the controller, PAV array is reset inside the controller, and the new PAV configuration is fixed in concrete (static) until the end of the next WLM interval, maybe 10 minutes later? Next came HyperPAV. IOS decides on an I/O by I/O basis if a PAV is needed for the next I/O, finds one from a pool of available PAV UCBs, directs the new I/O to a PAVed UCB which the controller knows how to send to the proper device, then IOS returns the PAV UCB to the pool of available PAV UCBs when the I/O ends. You don't have to reconfig. You don't wait until the end of the WLM interval. IOS does no control I/O to tell the controller a new PAV configuration. Instantaneously dynamic as opposed to quasi-static as opposed to seriously static. Bill Fairchild Rocket Software **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Hyper PAVs vs. Dynamic PAVs
In a message dated 9/12/2008 2:57:34 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Also, for the exaggerator in the crowd, the maximum WLM interval is 10s, not 10m. I wasn't exaggerating. I had no idea of its magnitude, and was guessing some number of minutes because of RMF's interval unit of granularity. HyperPAV cuts the interval down to the millisecond level, which is how long it takes for one I/O to run to completion. WLM's maximum of 10 seconds is worth about 10,000 such I/O requests. Bill Fairchild Rocket Software **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: KEY 8 CSA Usage
In a message dated 9/10/2008 6:20:17 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Also you can hire a lawyer to sit in the conference room with you and the auditors if you think it's going to escalate to that level of a conundrum. Wouldn't that by itself be tantamount to whistle blowing? I forgot. You are a lawyer. You don't need any help. Bill Fairchild **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: KEY 8 CSA Usage
In a message dated 9/10/2008 6:20:32 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: If I see you walking into an open manhole and say nothing, is that cooperation? Insufficient information given to answer. E.g., how far away are you? How fast is he walking? Is there someone right next to him in the act of warning or saving him from his doom? Another unnecessary, argumentative, and off-topic rejoinder, comme toujours. Unless the manhole is in key 8 CSA. Bill Fairchild **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: KEY 8 CSA Usage
In a message dated 9/10/2008 9:26:01 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: 1. Co-operate with the auditors. 2. Answer their questions as briefly (and consisely) as possible. 3.Don't volunteer any information. 4. Report, in detail, everything said to your direct manager. There is a conflict between 1. and 3. The only conflict is between the two choices of (1) answering each question truthfully but confining your answer to the narrowest possible context covered by the question and (2) answering each question truthfully while expanding your answer to include everything you know about the subject. To cooperate does not require volunteering. Not to cooperate could mean not to answer at all, to answer angrily or falsely, to change the subject with the answer, and a host of other ways one can avoid answering. I see no inherent conflict between 1 and 3. The conflict is created by putting more emphasis on 1 than on 3. A stretch of the imagination could even create a conflict between 1 and 4. E.g., what if something illegal and incriminating is discussed, and then the auditors tell you not to report to your manager? How can you cooperate with that? Another part of this equation is to remember that whistle-blowers are seldom (if ever) rewarded. Also you can hire a lawyer to sit in the conference room with you and the auditors if you think it's going to escalate to that level of a conundrum. Bill Fairchild Rocket Software **Pt...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty000514) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Vetting the Archives (Was: SMS - Delete)
In a message dated 8/29/2008 2:26:46 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Suppose there was a way to delete posts with wrong/bad information from the archives. Then, only correct/good information would remain -- increasing its value for research purposes. Is this possible? Maybe in some cases. But what if a post has good info in it not found elsewhere and also some bad info in it. Who decides whether or not to delete it? What if bad info is found out two months after it was deleted to have really been good info? Is the original poster of the bad info the one who must delete it? What if he doesn't want to or has dropped off the list? Who else can be allowed, or would want to volunteer, to clean up other people's bad info in the archives? What if a post with only good info is deleted by accident? Can it be undeleted? And so on... Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/25/2008 7:00:29 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I do find it distressing that experienced people on this forum would give advice about using non-programming interfaces such as CVTSRBRT. I didn't know until your post that using CVTSRBRT was not the optimal way to return from SRB code. I try to use an official interface when I know that there is one. Now I know, and I'll use R14 upon entry from now on. Thanks for the admonition. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
An accumulation of replies to multiple posts for this threat. 1. In a message dated 8/24/2008 10:54:51 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: How do you guys learn this stuff? So well? I mean, it's not like something they teach you in mainframe school, is it? We go to SHARE, where we share things, like knowledge, code, helpful hints, pitfalls to watch out for, sources of knowledge, doc, etc. etc. We contribute to and study others' contributions to common sources of helpful code, like the CBT tape. But most importantly, we all go back in time 30 or 40 years and start working with IBM operating systems when IBM mainframes were the dominant force and there were no PCs or other such Toys-R-Us software [IMHO] to distract us. It takes a long time to learn all this stuff, even when we have lots of help from helpful colleagues. Also back in those Jurassic days there were IBM educational classes, and then later also Amdahl-taught classes, in how all this stuff works. E.g., I attended a 2-week Amdahl class in MVS/XA operating system internals in 1985. I don't think such classes are available anywhere anymore unless you work for IBM, and they will send you to all the internal classes you need to work on whatever it is they hired to work on. 2. There's a tiny bit of setup required that the docs either don't mention, or I didn't see it. DROP SRB_ROUTINE DS 0H USING *,R6 LR R6,R15 The way to debug your own code on your own, with no help from IBM-MAIN, with your next problem like this is to start with the first instruction in your SRB routine, find somewhere in the dump or figure out somehow what must have been in R15 when the SRB code started to execute (some doc somewhere says that upon entry to an SRB routine R15 contains the address of the code to be executed), then simulate with pencil and paper the execution of each instruction by looking NOT at the instruction (e.g., BSOMEWHERE) but rather at the assembled object code on the extreme left of each line of the Assembly output. E.g, if it is a B instruction, then add the contents of what you know (or believe) to be in the base register of that instruction to the assembled displacement field in the B instruction, then subtract from that new address the value that was in R15 upon entry. This will give you the offset in your assembled code where you branched to next. If that new next instruction is not in your code, then you know you have your base register incorrectly set or else the USING is wrong upon which the assembly was based (those are the two most likely reasons). I suspect your code was assembled without errors (thus letting you assume it would also execute without error), you moved/copied some of it into the CSA location you had just gotmained, and the assembled offsets were all wrong for the new location of the code. You can start such an independent piece of code off with one of the following, e.g. USING *,R15 blah blah - or - BALR R15,0 USING *,R15 blah blah The first case assumes that some other code, like maybe the operating system, has correctly loaded R15 with the address at which this code is found in storage. The second case does not assume that, and initializes R15 so that the following displacements will be correct when the code executes regardless of where it is located in storage. This is an example of self-relocating code. 3. Someone else, not Lindey, wrote: What are you doing to save and restore the registers that you get when your code gets control? don't you have to have an R14 to return to, when your SRB routine is done? You can save anything you want upon entry to your SRB code so you can later study what was in the various registers if you want, but you don't have to save and restore anything in an SRB routine when you exit at the end. When you are finished, all you have to do is to arrive somehow at the one instruction in the dispatcher where SRBs are supposed to return to. One way to find it is this: L Rx,CVTPTR Get address of CVT L Rx,CVTSRBRT-CVTMAP(,Rx) Get Dispatcher's return address BSM 0,Rx Return to the Dispatcher where x can be any general purpose register except 0 CVT DSECT=YESGet CVT DSECT mapping It may be that R14 contains this address upon entry to the SRB code, and I would assume so, but I have never coded an SRB to return that way. I have always used the CVT pointer to the SRB return address within the Dispatcher, and that has always worked. I use this technique because I copied some working code once from someone else's debugged SRB, and that's the way he did it. And speaking of saving things upon entry, be careful where you try to save
Re: Why don't I see my CSA storage in the dump?
In a message dated 8/23/2008 8:02:47 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: I thought that instead of going wild and doing a bunch of SRB code that I should build the foundation first, meaning all the error recovery and so on. You should at the very least be thinking about recovery as you write new code. You can't really build the entire foundation first, since you don't know in advance everything you will have to free up or undo in your recovery routine until you have written the main code that acquires or does it. Write notes to yourself that you need to release such-and-such a resource later on, if ending normally or abnormally. Resources include CSA/ECSA acquired, locks held, and pretty much anything for which your code must be authorized to obtain or to do. The Authorized System Services Reference books will rapidly become good friends. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why don't I see my CSA storage in the dump?
In a message dated 8/23/2008 8:23:17 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: I just found a SETFRR macro. Do I use that? It isn't mentioned in connection with SRB's, but it may be supposed to be obvious. This seems like a good place to point out that you should start trying to find out these answers yourself before asking the IBM-MAIN world to help you with each problem you encounter. Look in the Authorized System Services Guide (but not Reference) and read the section on program recovery. That book also has a section on SRBs. You should read all of both sections before you try anything else and before you ask us more questions. Get the CBT tape if you don't already have it, and scan it for SRB routines that you can study and find out what others have done, then go read the IBM doc on what system services they are using (like IEAMSCHD, WAIT, POST, SETFRR, etc.). I am not trying to be a jerk, but sooner or later you will have to debug something and IBM-MAIN will not be around, or else you won't be able to wait for an answer from someone else. Ask us to explain something you find in the book but do not yet understand. Read up on the operator command CHNGDUMP in the appropriate IBM book. It will tell you how to get CSA, et al., dumped. A large part of the education we all had to go through was to learn in which IBM book the question was answered. Almost all questions are answered in some IBM book. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 9:39:54 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: .Do you have anything that needs re-locating? I would use directed LOAD. This means statements in your (Lindy's) program (the SRB routine that is to run in the other address space) like DC A(), where is a symbolic label within the program. If you dynamically acquire storage somewhere (whether CSA or not) and then move executable code into that storage, which is one way to get your SRB routine into CSA, you will have to write the code yourself to relocate all such address constants. A directed load means you acquire the storage, then code the LOAD macro to load your module at the specific address of the storage you just allocated. This assumes your load module is in a separately loadable module in a library somewhere. If it is simply a small part of your program that is not in a separate module, then you will have to copy the code into the storage yourself, then relocate the address constants in the copy. Or else relocate them in your code,then copy the code. But this means your program stores into itself, which may not be a good idea. Or you could add some code into the SRB routine that does the relocation once it starts to execute. This is called self-relocating code, and is something I did a lot of back in the days of DOS/360. Do something like this: SRBRTN ... beginning of code that runs in SRB mode in another address space LA R0,blahblah ST R0,adressxyz ... blahblah xxx more executable code ... adressxyz DC A(blahblah) This code will correctly relocate the address constant no matter where the code is loaded into storage. If you do an undirected LOAD, the LOAD process handles all the relocation of relocatable address constants into whatever load address the LOAD macro picks for your module to be loaded into. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 6:44:04 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: it runs to completion, but I can't tell if it worked or not So running to completion is like working as coded. All code ever written works as coded. One way to know if it works, after you fix all the problems you discover with LOGREC et al., is to put a WTO at the very end. Of course, you have to code the WTO so that it does not use an SVC (LINKAGE not = SVC; some macros allow LINKAGE=SYSTEM, others allow LINKAGE=BRANCH; check the WTO doc). And remember that the WTO system service will alter some registers. Check the WTO doc to see which ones. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 1:55:15 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Which parameter on IEAMSCHD tells it the address space it is to run in? TARGETSTOKEN. Specifies the space token (STOKEN) of the address space in which the SRB routine is to receive control [meaning run in]. Next you'll have to find out how to get the STOKEN for the address space in which you are interested. I don't know for sure, but I would try looking in the ASCB DSECT (the macro is named IHAASCB). It'll be my first SRB. Good luck. :-) Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 3:01:38 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: I don't know yet what an STOKEN or an ALET is. A token, in general, is an arbitrary value that is long enough so that all tokens for the same class of resource will be unique. Whenever certain kinds of events occur, a new, unique token is created and is always associated with the resource involved with the event that just happened (a new address space is created, e.g.). An STOKEN is a token that is unique to a Space (hence the S at the beginning of STOKEN), where space means address space. There are other types of tokens in z/OS; e.g., each task in an address space has a unique TCB token, each time an I/O configuration change occurs a new I/O configuration token is created, etc. Tokens are used to identify uniquely which of a set of similar resources is to be involved with certain kinds of system services. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 3:28:25 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: My current goal is to run VSMLIST in a target address space. Whatever you try to do in an SRB routine, make sure you don't code any system services that have an SVC instruction in their macro expansions. SVCs cannot be executed in SRB mode (except for the ABEND service, which uses an SVC). Most system services now have a parameter that governs whether the macro expansion will use an SVC or something else (PC or BALR perhaps). Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trying to figure out IEAMSCHD
In a message dated 8/22/2008 4:22:45 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Ok, Bill. Lightbulb time. It's tucked away in the ASSB. ASSBSTKN. The OS creates it when it creates an address space. Glad you found it. I haven't yet learned a good rule of thumb as to why some address space-related fields are in the ASCB, ASSB, or the ASXB. Sometimes I find the control block that has field X in it by doing an ISPF 3.14 with something resembling X in the search field and the data set name is first SYS1.MACLIB(*) and then SYS1.MODGEN(*) if necessary. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: A couple of memory/storage questions
In a message dated 8/19/2008 2:08:39 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: I played with something similar many years ago. IIRC, I used ESAR, SSAR and MVCP instructions to pull information from other address spaces. I did something similar once. You have to make sure that the target address space is swapped in first. You start out with addresses that are in common, such as ASCB, then work your way down pointer chains. It is mainly useful for system control blocks. Some of the system control blocks related to an address space are always accessible, but most are swapped out along with the rest of that address space's storage when it is swapped out. Find the DSECT for the control block in SYS1.MACLIB or MODGEN and read all the comments at the beginning of the DSECT. There is usually an explanation in there as to what subpool the control block is in, then go to the Authorized System Services Guide to find the various attributes of that subpool. If you really want to map out all the storage used by address space X, you can also try to find all its data spaces and also all the storage it has acquired above the bar. Sounds like a fun learning project for one's sand box system. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: DASD Space Allocation
In a message dated 8/18/2008 7:24:37 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Total max extents vary depending on whether SMS stripping and/or extended addressability which would put the max at 4080 extents. If Extent Constraint relief is used, then the max is 7257. Then there is the relatively new feature called Extent Consolidation. If a new extent is needed, the system finds an available extent according to all the previously discussed limits (per volume, max number of voumes, etc.). If this new extent begins exactly at the next track after the end of an already allocated extent, then the new extent is consolidated with the one already allocated. This does not mean you end up with more than 4080 (or 7257) total extents, but it does mean that you may take a trip through data set extend many more times than you end up with distinct extents to show for the trips. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Unbelievable Patent for JCL
In a message dated 8/19/2008 3:45:43 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: AFAIK the first software patent was granted to Martin Goetz of Applied Data Research, Inc. (ADR) in the sixties... I remember seeing this event well-publicized in the trade journals at the time. A colleague of mine and I jokingly came up with a new product idea once for allocating files, deleting files, and many other useful functions. Now I see I can also patent it. It's called IEFBR14. Bill Fairchild Rocket Software **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: A couple of memory/storage questions
In a message dated 8/18/2008 11:03:56 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: What is the advantage of freeing an entire subpool vs. freeing the memory by address? There is no advantage if you only have one piece of storage involved. If you have ten thousand pieces of storage, the advantage is one FREEMAIN versus ten thousand FREEMAINs. Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut000307 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: MIPS /day
In a message dated 8/15/2008 9:26:45 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I realise it's old, but I've had salesmen talk in MIPS even after that. And I have heard technical people who know better continue to use the term channel-unit address, CUU, or device address when they really should be saying device number. They still build new software that displays this obsolete term externally to users. The operating system thing called CUU was changed to device number with the advent of S/370/XA around 1983. Unit address is a meaningful term used correctly within a control unit, but not from the point of view of the operating system. Once a term becomes engrained, it is hard to replace. That's why I still sometimes think of, but don't let myself speak, the phrase low core. Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut000307 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: MIPS /day
In a message dated 8/14/2008 10:50:44 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I also had a same issue when my client wanted to know, how much horse power was being used by his application, and no such standard tool I could find out there. Instead I used the following formula; CPUTIME / (ACTUAL INTERVAL DURATION * NUMBER OF CPS) * TOTAL MIPS And this computation results in some number of foot-pounds per second? lol Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-Volkswagen-Jetta-2009/expert-review?ncid=aolaut000307 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: California's COBOL payroll system
In a message dated 8/11/2008 8:08:40 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I did not allow my daughter to use a calculator until she was in college! There I had no control I think it is all right to use a calculator if one is still adept at the pencil and paper method. E.g., I use a really big one whenever I need to do basic arithmetic on binary numbers. It's called a mainframe computer. Now that we're back on topic, how about WE KILL THIS THREAD? Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000517 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Politics - California state computers can't handle pay cut, controller sa...
In a message dated 8/5/2008 3:52:31 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: The Bee laid off their technology reporter - I heard they are having budget hard times. No wonder considering that they do such a poor job at tso many things. During the year that I lived in the Sacramento area (1997-1998), I observed that the average edition of the SacBee (Sacramento Bee newspaper) used about 60% of its pages for advertising automobiles for sale. That newspaper was so bad that my colleagues and I renamed it the SuckBee. Apparently it continues on doing a poor job at nearly everything. Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000517 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Politics - California state computers can't handle pay cut, controller sa...
In a message dated 8/5/2008 4:34:02 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Additionally, the payroll system is completely table-driven, for taxes and salaries, so this change should only take a short while to accomplish, not the six months asserted by controller John Chiang. When I read the first post by someone who assumed that Chiang was telling the truth, and therefore the taxes and salaries were hard-coded, I didn't believe Chiang either. The SuckBee is not the only source of extreme error here. Chiang, being a controller, is a political creature. All we know for sure is that he wants the public in California to believe that changing the programs cannot be done and is floating various reasons why, which wise readers should assume are bogus, exaggerations, or lies until proven otherwise by competent technical experts with no political agenda. Reading something like this makes one wonder about the veracity of all news reported. Political news is invariably at least 99% lies, rumor, innuendo, propaganda, disinformation, and/or garbage whether found in print or on the television (American TV, most especially). When I read text in IBM's Principles of Operations that explains how the Load Address instruction works, I believe it. When I see or hear political news I laugh. Prussian Prime Minister Prince Otto von Bismarck summed it up thus: “Never believe anything in politics, until it has been officially denied.” Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000517 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Datasets with KEYs
In a message dated 8/6/2008 10:36:19 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: ISAM. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of William Hecox Sent: Wednesday, August 06, 2008 10:27 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Datasets with KEYs Hi, I need to create and populate a NON-VSAM Dataset that contains KEYS. Is there an IBM utility I can use to do this? Bill ISAM is not an IBM utility. It is an access method which is about to become seriously unsupported by IBM. I suspect you will have to write your own utility whose design is similar to that of IEBGENER; i.e., read one logical record using QSAM from the input file, add that record to the output buffer; repeat until the output buffer is full, then write it to the output file using BDAM (q.v.). Alas, there is no QDAM, so you have to do the blocking on the output side yourself. If ISAM were to continue to be supported, you could write the logical record to the output file using QISAM and your one-time special-purpose utility program would be simpler. But you will still need to write the utility program yourself. Or find it on the CBT, maybe. Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000517 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Datasets with KEYs
In a message dated 8/6/2008 10:27:11 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I need to create and populate a NON-VSAM Dataset that contains KEYS. Thinking about your query some more made me realize you didn't give us enough technical specifications to help you very much. E.g., what do you mean by populate? What do you mean by contains keys? Namely, will the data set be blocked or unblocked? If unblocked, you might even be able to use IEBGENER and specify the key location and offset through JCL. If blocked, then what does the block's key represent - the lowest key of any record in the block, the highest key of any record in the block, or something else? Must all the keys written onto the tracks be in ascending key sequence, descending, or is random OK? What will happen if there are two blocks somewhere in the data set with the same key? How will this data set be accessed after its creation? With what software and/or access method? What will said accessing programs do if a key is not found? What happens if a block is found with no key on the track? How long will this data set exist? How do you plan to back it up and restore it if necessary? Will it be automatically managed by some kind of archival system? I don't expect answers to all of these, but you definitely need to think about these issues. Bill Fairchild Rocket Software **Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000517 ) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Example of what a very small JCL Interpreter can do to your installation.
In a message dated 7/29/2008 3:25:25 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Suppose someone who does not know that proc X is used by 10 other jobs with overriding DDs in them decides to rearrange the DD statements within proc X. Why ever would anyone do that? Possible reasons: 1. When I create JCL, I put my DD statements in alphabetic order by ddname within each step. It helps me find one later if I need to. My JCL is not used by others, so I am free to reorder my own DD statements according to whim. Someone with the same desire to alphabetize everything may cluelessly reorder a proc that others use without understanding the repercussions of what he is doing. 2. People make mistakes regardless of how clueless or anal retentive they are. Maybe somebody is editing a proc, accidentally deletes a DD statement, then realizes his mistake, recreates the now missing DD statement, and puts it in the wrong place because he doesn't remember exactly where it was in relation to the 20 or 30 other DD statements and he doesn't know that exact placement may be critically important. 3. Why would anyone ever do anything stupid? Never. Does that mean that stupid things never happen? 4. My program can never get to this point in the logic, so I don't need any code here to handle this situation. 5. As Donald Rumsfeld said, Stuff happens. Bottom line: software and procedures should be bullet-proof enough to survive situations that occur for reasons that make no sense to those of us who are rational, competent, wise, and blessed with huge amounts of experience. Bill Fairchild Rocket Software **Get fantasy football with free live scoring. Sign up for FanHouse Fantasy Football today. (http://www.fanhouse.com/fantasyaffair?ncid=aolspr000520) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: MIDAW and Dynamic Activation
In a message dated 7/29/2008 6:55:10 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: The final check is when we look at the UCBMIDAW bit in the UCB involved. If a channel program tried to use MIDAW and it was disabled on the system level, IOS would fail the channel program with a PGM CHECK. I look at that same UCB bit and nowhere else. I trust the rest of the operating system to turn the bit on if the processor, controller, device, and parmlib settings all allow it. So far I haven't gotten any channel program checks, which by the way are detected by the Channel Subsystem (part of the processor hardware microcode) rather than IOS (software component of the operating system). Bill Fairchild Rocket Software **Get fantasy football with free live scoring. Sign up for FanHouse Fantasy Football today. (http://www.fanhouse.com/fantasyaffair?ncid=aolspr000520) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Example of what a very small JCL Interpreter can do to your installation.
In a message dated 7/28/2008 10:55:50 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I certainly remember (though obviously not as clearly as Mr. Blair) a day and age when overriding DD statements were required to appear in the same order as the overridden DDNAMEs in the proc. I was delighted to see the constraint relaxed. Suppose someone who does not know that proc X is used by 10 other jobs with overriding DDs in them decides to rearrange the DD statements within proc X. Which mode of processing by IBM would be better? Another possibility is that beaucoup jobs use overrides for a universally available vendor proc like ASM, LKED, FDRxxx, CAwhatever, etc., and then the vendor decides to rearrange the DD statements within the distributed machine-readable PROCLIB containing that proc. Yes, I know, we can blame change control when the inevitable errors are found. But it would be better to avoid the errors than to find someone to blame when they occur. This situation seems to me to be analogous to users' building job streams that use output from utilities like IDCAMS as their input and require data set names to begin in column X and volser in column Y, e.g. Then IBM changes the format of the utility's output. And it's not limited to IBM. Data centers also have locally developed programs that generate SYSOUT which is then used as input for other programs, and the developer in charge of a utility cannot be expected to know all the downstream users of his SYSOUT. Bill Fairchild Rocket Software **Get fantasy football with free live scoring. Sign up for FanHouse Fantasy Football today. (http://www.fanhouse.com/fantasyaffair?ncid=aolspr000520) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: HSM recall on one LPAR for request on another lpar
In a message dated 7/16/2008 6:29:53 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: What is the risk? One possible risk is that the sandbox LPAR can crash while holding a reserve done by HSM, which then locks up some process on the prod LPAR. I crashed a test system once while it held a reserve on the JES2 checkpoint data set which caused the prod system's JES2 to get very unhappy. Bill Fairchild Rocket Software **Get the scoop on last night's hottest shows and the live music scene in your area - Check out TourTracker.com! (http://www.tourtracker.com?NCID=aolmus0005000112) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: IBM using more below the line storage.
In a message dated 7/9/2008 4:50:06 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Looks like a bit of do as I say, not as I do. It's been my experience that it's much better to do as they say. New applications should exploit storage above the bar as much as possible, IMHO. Bill Fairchild Rocket Software **Get the scoop on last night's hottest shows and the live music scene in your area - Check out TourTracker.com! (http://www.tourtracker.com?NCID=aolmus0005000112) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: STARTIO macro doc
In a message dated 7/8/2008 6:03:32 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: If you really want to do it yourself, here are a few things to consider before you jump too far in. 1) Modify OPEN/CLOSE/EOV code to intercept the open and close 2) Intercept device allocation 3) What do you do when DASD gets full? Move data to real tape? Delete oldest? 4) If for #3 you move to tape, how about catalog maintenance? 5) The above have not even started to scratch the surface of all the problems and hurtles that you have to overcome. It is not necessarily easier, but it is more fun (in my weird opinion) to intercept the STARTIO request some time before the SSCH happens (there are several different places where you can do this by front-ending different IOS modules), steal the I/O away from IOS [1], scan the tape I/O channel program's CCWs to determine what it is doing and build a DASD channel program to do the same thing (write a block, read a block, etc.) to a DASD file somewhere, do the DASD I/O, copy its ending status into the equivalent ending status for a real tape device, and finally unsteal the I/O back into IOS [1]. This is seriously difficult stuff, and you will crash your test system many, many times before you are done. You really don't want to do this unless you have a lot of time on your hands, a fire in the belly to learn how IOS internals works, and a fat budget for education or development. There is at least one commercial product that does what you want - redirects the I/O to a real DASD device, and it works pretty much the same as in my footnote [1] below. OTOH, modifying O/C/EOV and device allocation is no picnic, either. There were two separate presentations on STARTIO at the August 1987 SHARE in Chicago. I distributed a sample program to read a DASD volume label using STARTIO to all those in attendance, and this document was published in the proceedings if you can find them. Bill Fairchild Rocket Software [1] This means to render the request temporarily unstartable (there are a number of different and easy ways to do this, including never letting the request be put into the queue), pass a pointer to it while POSTing another address space that analyzes the tape channel program, does the equivalent DASD I/O after validating the possibility of doing it at all (file full, etc.), analyzes the result, fills in the original IOSB's status info (you also have to reflect back the tape device's equivalent error status if things go wrong), then invokes the appropriate IOSB exit to post status back to where the original I/O requester can find out that the tape I/O has ended. I did all this once (not for tape, though), and it took a very long time to get it right. I had the time, the fire in the belly, and the budget. A major part of the difficulty is the large variety and complexity involved in scanning a channel program and supporting all the possible ways of chaining CCWs, all the CCW flag bits, all the types of indirect address lists, and so on. You have to write code that emulates a large fraction of five of the Principles of Operations' most incomprehensible and somnifacient chapters (13-17) in addition to a large fraction of the book that describes how a tape device's CCWs work. Oh, yeah, and the DASD book, too, so you can build the correct DASD channel program. **Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut000507) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: want to read a dataset in use
A similar question was asked a few months ago. Check the archives for more ideas. Bill Fairchild Rocket Software **Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut000507) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Strange Problem: System Code S106
In a message dated 6/26/2008 10:36:31 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: My first thought is that the invalid CDE should be removed by LOAD processing if the LOAD fails. But there's also a good case for fixing the problem that led to the S106 Abend as well. I don't see how leaving a bogus CDE in the system can possibly help with the task of fixing the problem that led to the S106 ABEND. Bill Fairchild Rocket Software **Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut000507) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Strange Problem: System Code S106
In a message dated 6/26/2008 11:27:46 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Another workaround for us is: don't use the address in the CDE entry, if it is zero or X'8000'. I have seen another case of a control block's containing a full word of X'8000' that was supposed to be an address. I saw an IOSB one day that had one of its five exit addresses set to X'8000'. IBM code didn't build that IOSB. Vendor code did. The high-order bit is interpreted for setting the addressing mode by the component that calls the exit routine, and if the exit address is zero then a default IBM exit is used instead. That I/O request worked correctly, implying that IBM's IOS code tested only the right-most 31 bits for zero. Perhaps all our user code should be written similarly; i.e., if we inspect a field that is supposed to contain either an address or zero, then we should assume the worst case for the contents of that field, namely that the high-order bit is unpredictable as it is not strictly part of any address stored in that field. Bill Fairchild Rocket Software **Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut000507) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Op codes removed from z/10
In a message dated 6/25/2008 9:17:49 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: ... a number of linkage assist instructions that were never publicly by IBM documented to my knowledge. IBM documented the five mentioned by the OP in an extremely thin generally available publication in ca. 1983 or 1984 that was titled something like S/370/XA Processor Assist. I believe that this book was also the first public documentation on the (at that time) new Control Register bit that governs Low Address Protection. I had a copy of the book for a decade or two. I also vaguely recall that another pair of assist instructions were to set and remove an FRR. Bill Fairchild Rocket Software **Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut000507) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: EXCP access methos
In a message dated 6/11/2008 7:27:53 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: I wish there was a documented interface to STARTIO; I'd like to play around with Format-1 CCW's. :-) In AUG 1987 there were two sessions by two different presenters (I was one of them) at SHARE in Chicago on how to use STARTIO. In my session, I distributed a simple, sample program that used STARTIO to read the volume label from a DASD volume. If you can find this session in the SHARE archives, that handout is in the proceedings. IBM has not chosen to make STARTIO an externally documented interface. The main danger in using STARTIO is when you build a channel program with real addresses that has read CCWs in it, as you can easily overlay storage that is not yours. Write CCWs will not overlay storage, but you will write the wrong data out to the I/O device if you get those real addresses wrong. As with any other authorized service, STARTIO must be used cautiously. Or, as Ed Jaffe suggested, you can use Format 1 CCWs with EXCP in unauthorized code. If your code is authorized, there is a lot more you can do by modifying DEB fields after you OPEN your DCB. Bill Fairchild Rocket Software **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Outsourcing dilemma or debacle, you decide...
In a message dated 6/12/2008 9:39:09 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I am curious however, exactly what it is that the supposed senior systems outsource person knows, and exactly what has he done before, obviously it isn't much. I wonder if he even knows how to spell I-B-M. The company that is doing this will probably blame the inevitable debacle on IBM. Bill Fairchild **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Outsourcing dilemma or debacle, you decide...
In a message dated 6/12/2008 10:47:45 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Sorry, but I think you are making it very wide. I disagree, if by wide you mean exaggerating the problem. Some companies really give up on hiring from inside the Country moving the services to overseas, but people overseas are almost as skilled or even more skilled. They are just cheaper. No disagreement with this. As to the fact of terrorism it will always depend on what kind of company one will contract. You can always suffer from terrorism from inside also. Nobody said anything about terrorism. Now you are making it very wide. The entire discussion so far has been about experience and, most importantly, COMPETENCY. A business is free to move everything anywhere it wants (if legal), and can also hire only totally incompetent and unskilled workers, but then someone will have to train those workers and get them up to speed. If their employer won't do it, then the employer should be expected to suffer financially as a result of the incompetence of its management. Bill Fairchild **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Outsourcing dilemma or debacle, you decide...
In a message dated 6/12/2008 11:16:19 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Can you say cyber terrorism? [from a post by Tom Kelman at Commerce Bank of Kansas City which is where this comment came from.] Sorry. I missed that post. There is also management terrorism, in which incompetent management blunder their way into eventual dissolution of a good company. I have worked at more than one place like that. Bill Fairchild **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: EXCP access methos
In a message dated 6/12/2008 11:42:05 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Real CCW addresses are also used by the documented EXCPVR interface. True. And you have to get the real addresses correct with EXCPVR, or you will hose storage on read commands. The biggest problem with STARTIO is that there is no allocation, DCB, or OPEN required. I never considered this a problem but a major benefit, and one of several reasons why I use STARTIO. If you are authorized enough to use EXCPVR, you can also use EXCP, modify the DEB, and get to any device which you have not allocated, enqueued upon, or OPENed a DCB for. There are times when such things are necessary. The lower the level access method you use, the more flexibility you have, the more things you can do, sometimes the more things you have to do (e.g., block/deblock with BSAM but not with QSAM), and, at a low enough level, the more dangerous it becomes. All it needs is an IOSB -- which contains pointers to the channel program and UCB. Using STARTIO, you can construct a channel program to read or write any records anywhere on any device. This puts you one subtle programming error away from wiping out something important that isn't yours. Which is why you test your STARTIO code, and anything else you build that is authorized, on test systems that everyone else knows may not survive your test. You can also wipe out something that is not yours with an incorrect real address on a read command using the much safer EXCPVR. When you are building authorized code, you must write each instruction with the awareness that you can unexpectedly hose almost any conceivable part of MVS if you err. The other danger is having to write code that executes in SRB mode -- with PSW key zero -- to manage I/O completion. Many posters have demonstrated a familiarity with coding SRBs. I assume a poster is competent enough to do whatever is necessary whenever he finds out whatever prompted him to post a question. The original mention of STARTIO seemed to me more like intellectual curiosity than a desire to build a production program with possibly massive, hidden dangers in it. There are plenty of other dangers, too; e.g., in STARTIO you must build your channel program in and have all your data in fixed storage, and also make your address space nonswappable. You can screw up either of these and possibly hose something. Without question, STARTIO is a dangerous interface -- made even more dangerous by the total lack of documentation on its use. Not completely total. Only officially. Long ago intrepid developers discovered several IBM software products using STARTIO (JES3, IMS) whose source code was distributed, and they copied the code surrounding those STARTIOs. I learned how to do it from a photocopy of a photocopy of a ... from someone in Amdahl in 1985. And when I explained publicly how to use STARTIO in SHARE, I emphasized many times how easy it was to hose things with STARTIO and to be very, very careful. Bill Fairchild Rocket Software **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Outsourcing dilemma or debacle, you decide...
In a message dated 6/12/2008 12:30:46 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: But the lesser skilled work will be outsourced again to those who need the money enough to be willing to work for less Just as manufacturing jobs are migrating from one outsourced country to another when the first location's cost of production rises too high. Ralph Nader calls this the race to the bottom. Perhaps ultimately everything on earth will be made in Haiti or Botswana. Bill Fairchild **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: EXCP access methos
In a message dated 6/11/2008 8:25:57 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: It's my understanding that for many decades EXCP has not executed channel programs in place and as provided by the caller. Back in the days before paging systems, back when there was no virtual or real storage, back when storage was just called storage, EXCP would execute the channel program in place and as provided by the caller, but with extra CCWs in front of the caller's first CCW. These extra CCWs were added to insure data set integrity; i.e., the caller's channel program cannot go to any track that is not in the list of allocated extents created by OPEN. I don't remember for sure, but it was probably possible for a caller to have a read command executed with a storage address that would cause data being read to overlay storage that was outside his region, partition, or whatever the big chunk of storage was called. So you could clobber the operating system as well as other users' central storage with read commands. The various DASD access methods on these systems (OS/360, DOS/360, TOS/360, and BPS/360) were QSAM, BSAM, BPAM, BDAM, ISAM, and QISAM. They all used EXCP internally to do I/O requests, except for possibly ISAM which sometimes had a naked SIO instruction (or so I was told). I don't know very much about the other access methods for devices other than DASD and tape (e.g., TCAM, QTAM, and BTAM), but I would guess that they all also used EXCP internally. With the advent of virtual and real storage, IBM chose to require that the data addresses inside CCWs be interpreted by the I/O hardware as real addresses. Thus a scheme was needed to convert from virtual addresses to real addresses in order to make the transition to the new systems transparent to customers. The MVS architects decided to create a new I/O concept called IOS Driver which is a new layer of software that performs I/O requests without having to use EXCP. They also invented a new access method called STARTIO which replaced EXCP as the lowest possible level access method. The ancient DASD access methods, QSAM etc., still use EXCP, but EXCP was redesigned to interface between the callers of EXCP (ancient access methods), which present EXCP with channel programs containing virtual addresses, and the new lower level and thus intermediate, internal access method called STARTIO, which assumes that the channel program is in non-pageable storage, with real addresses of data, and which was built by a trusted software component. Many new functions in MVS were designed to use STARTIO directly themselves, such as the paging supervisor, while some new MVS components were designed to use EXCP, probably in order to get the new code written most quickly. JES2, e.g., originally used EXCP (I haven't dealt with JES2 internals now for 20+ years, so it may be different now), probably because JES2 was developed from HASP, which used EXCP, and that code was already well debugged, so why rewrite it? Rather, they are moved to protected storage so the user can not modify them on the fly Yes, unless you have EXCP appendages, but these must be loaded from an authorized library, so the customer can control their use. they are prefixed to prevent seeks to prohibited tracks; virtual addresses are translated to real; etc. I'd further expect changes to CCW architecture to accommodate XA and later 64-bit addressing and new I/O architecture. Correct on all counts. So the checks to prevent it may be a matter of IBM's resource allotment: rather than continually update EXCP code to all new hardware features, it's easier simply to prohibit use of EXCP for such purposes. I concur. Also IBM would like to encourage users to migrate all applications to the latest and greatest software and hardware solutions; namely, VSAM, DFSMS, ESS controllers, etc., so typically IBM adds support to strategic products and components first and then maybe, reluctantly and much later, to non-strategic components. They, too, have limited resources for developing new products and adding support for new products into other, older, products that must interface with the new products. It has always struck me as bizarre that the OS supports running channel programs built by problem-state programs. This is secure only if the channel programs are in effect interpreted rather than executed directly. A more rational layering of functions should have channel programs built only by trustworthy supervisor-state code. I don't know to what you are referring here by the OS. Problem-state programs in z/OS build channel programs which are then converted to safe, trusted equivalent channel programs by trusted software components before being started by IOS. In VM, CCWs are not interpreted as far as I know, but rather the channel program is scanned before being
Re: EXCP access methos
On Wed, 11 Jun 2008 10:41:11 -0500, Rick Fochtman [EMAIL PROTECTED] wrote:_ (mailto:[EMAIL PROTECTED] wrote:) IIRC, VSAM and the VSAM-like access methods use STARTIO directly. In a message dated 6/11/2008 5:36:57 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Directly? I thought that the move had been to use the Media Manager. I don't know what VSAM-like access methods are. For the last 15 years or so (or more) IBM has used the Media Manager to do DASD I/O in its new, strategic software products (e.g., DB2). VSAM has been an official access method since the introduction of paging operating systems in the mid-1970s. The Media Manager uses STARTIO to do its I/O. Bill Fairchild Rocket Software **Vote for your city's best dining and nightlife. City's Best 2008. (http://citysbest.aol.com?ncid=aolacg0005000102) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: DASD or VIO
In a message dated 6/4/2008 5:26:43 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: How can i determine in an assembler program whether a dataset is allocated on dasd or vio? Find the UCB for the device allocated to the data set. One possible way to find the UCB is to find the data set's entry in the TIOT. If you know the DDName, you can scan the TIOT looking for the same DDName. The TIOT entry has the UCB address in it. Add the UCB mapping DSECT IEFUCBOB to your program. If the field UCBJBNR in the UCB has the UCBVRDEV bit on, then the device is VIO. Also the field UCBDUMMY should contain the EBCDIC string VIO. Bill Fairchild Rocket Software **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Advertising on IBM-MAIN (Was: IBM PR: PCI Security Compliance Workshop in...
In a message dated 6/4/2008 1:10:19 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: know that I advertise occasionally for the MCMG group that I go to in Chicago. I'm glad the Sam Knutson advertises for the group in DC area, and Mark Nelson advertises the New York Naspa chapter's group that is meeting in 2 weeks. And a score or more posters advertise and/or freely discuss each upcoming SHARE. Which makes me wonder now why I haven't seen any discussion of the annual national CMG meetings. A large % of their sessions revolve around IBM mainframe computers. Just wondering... Bill Fairchild Rocket Software **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Advertising on IBM-MAIN (Was: IBM PR: PCI Security Compliance Workshop in...
In a message dated 6/4/2008 2:22:58 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: And speaking of advertising on IBM-MAIN, where did this come from in my last post? What odes AOL Food have to do with IBM mainframes? I didn't type it into my email. It BEGIN WEIRD INSERTED TEXT **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (_http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302_ (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) ) END OF WEIRD INSERTED TEXT I just sent an email to myself and discovered the weird text in there, too. It seems that my AOL is generating it. It is not part of my auto-signature. How do I turn off this trash? I apologize for all the times I've inadvertently sent junk like that to IBM-MAIN. Does the NSA also inserted invisible messages in all emails now? Bill Fairchild Rocket Software **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: re; American Airlines
In a message dated 6/3/2008 11:31:03 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: there were some early -13 ( -23) literature showing 90percent cache hit rate. i pointed out that the example was actually 3880 with 10 records per track and reading sequentially. I remember a SHARE session in which a control unit guru from IBM-TUCSON described the wonderful new DASD Fast Write feature of the 3990 (AUG 1993, I think). She told the audience that IBM had done extensive modeling and was convinced that 4MB would be enough NVS for all possible workloads. But just in case it wasn't, IBM was making 8MB also available as its maximum possible NVS size. Bill Fairchild Franklin, TN Disinterested intellectual curiosity is the life blood of real civilization. [G. M. Trevelyan; 1942; English Social History] **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Monitor use of Load-Library as JOBLIB/STEPLIB
In a message dated 6/3/2008 2:29:23 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: If one knew the names of the PDS' in question, I assume one could discern the concatenation order. With that knowledge and the name of the program that was loaded, it should be, somewhat, simple to firgure out which PDS made the contribution. Some simple coding should do the trick... Would it not? Not if the simple coding runs after the record has been written and the contents of the PDSes have had time to change. And how would one know the names of the PDSes in question? Read a PROCLIB looking for the PROC? Read some other kind of library looking for the JCL? And what if those libraries have changed? The most accurate way is to gather the information from the appropriate data source when building the record. Down stream = possibly down level. Bill Fairchild Franklin, TN Disinterested intellectual curiosity is the life blood of real civilization. [G. M. Trevelyan; 1942; English Social History] **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: American Airlines
In the ESS/2105 book I have, there is an entire chapter on the Multi-Path Lock Facility. There are also some options that can be set in the Define Extent operands that are ACP (now called TPF, the Transaction Processing Facility) specific, such as record caching. These facilities were supported in some earlier control unit generations (e.g., 3990). Bill Fairchild Franklin, TN Disinterested intellectual curiosity is the life blood of real civilization. [G. M. Trevelyan; 1942; English Social History] **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: PPRC and page datasets
In a message dated 5/8/2008 2:17:54 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: We established a PPRC Metro Mirror - Loop Back environment, which means that we PPRC from the front end of the box to the back half of the box. We were told that in a metro mirror with 30 kilometer separation in full Synchronous mode, the delay could be up to .08 ms on writes. Since our loop back metro mirror is approximately 3ft, our delay is less than .03 ms. on writes. Thanks for the details on your normal daily backup cycle. I just have one question. The difference between .08 ms. and .03 ms. is .05 ms., or 50 microseconds. Do you really need to reduce write elapsed time by that small an amount at the cost of having your secondary mirror devices in the same room as your primary devices? You must be seriously write-intensive with very low I/O service times for 50 microseconds to be a large increment in service time. Bill Fairchild Rocket Software **Get trade secrets for amazing burgers. Watch Cooking with Tyler Florence on AOL Food. (http://food.aol.com/tyler-florence?video=4?NCID=aolfod000302) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SVC 27
In a message dated 5/13/2008 8:41:05 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: How to use OBTAIN is documented here: _http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DGT2S341/1.3._ (http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DGT2S341/1.3.) Another way to learn about the SVC 27 parameter list is to assemble multiple OBTAINs with different parameters and study the code generated and their comments. Bill Fairchild Rocket Software **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: 3 Page Datasets on one Volume
In a message dated 5/7/2008 11:57:26 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: If I am right that resume subchannel is no longer used by ASM, than putting other low to medium use datasets on the same volume will make little or no difference to paging performance. The devil is in the details of the definition of low to medium use. If such a data set is sequential and it is not used for days on end, when it is finally used it may easily be accessed hundreds of times per second for however long it takes to read or write the entire data set. If there is a need for high paging performance during this burst, then paging performance will likely suffer. There are several things that paging can do to get its I/O request ahead of others in the queue (e.g., use of the IOSXIMEX flag bit in the IOSB), but I don't know if paging I/O does this. And paging I/O interrupts are processed ahead of other pending interrupts, I believe, thus allowing the next paging I/O to be started ahead of others. Bill Fairchild Rocket Software **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: PPRC and page datasets
In a message dated 5/8/2008 10:05:07 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: We're backing up over 4,000 addresses - a lot of which are mod-27's. Can you describe this backup process a little? E.g., I assume you use some kind of FlashCopy. If so, then you need 4,000 more addresses for their secondary volumes, right? How much total elapsed time does it take to do all those backups? How many output tapes are produced? What DASD vendor? If you start all 4,000 FlashCopies at once, how long does that take? Total down time for the backup site before you start mirroring again? How long to get back in sync? This sounds like the kernel of a good session for SHARE or CMG. Bill Fairchild Rocket Software **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: 3 Page Datasets on one Volume
In a message dated 5/8/2008 8:54:18 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: Yes, SUSPEND/RESUME is no longer in use, on supported releases of z/OS. No longer in use by the paging subsystem. But still in use by XCF, at least it was the last time I looked at a GTF I/O trace. And some vendor products, probably. And that's just DASD I/O that uses it. I have no clue about other device classes' use of suspend/resume. Bill Fairchild Rocket Software **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: OT:Gas Prices -- KILL THIS THREAD
Is there another place on the Internet where the price of gas can be discussed? Bill Fairchild Rocket Software (and not Rocket Gasoline Company) **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: APAR acronym
IBM may want us to think an APAR is an Authorized Program Analysis Report, but I'm not going to let them fool me. I know it is really a three-banded South American armadillo (Tolypeutes tricinctus). Check it out: _http://www.thefreedictionary.com/apar_ (http://www.thefreedictionary.com/apar) Bill Fairchild Rocket Software **Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: TIOT filling up: too many dynamic concatenations
In a message dated 4/16/2008 12:28:54 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Authorized programs are not constrained by traditional limits on TIOT size and 24-bit virtual storage. ... Such programs can support literally hundreds of thousands of simultaneous allocations. They can also do I/O without any allocation, TIOT entry, DD statement, enqueue, open, etc. All they need is a UCB address, some CCWs somewhere, and about 150 bytes of ECSA. Bill Fairchild Rocket Software **It's Tax Time! Get tips, forms and advice on AOL Money Finance. (http://money.aol.com/tax?NCID=aolcmp0030002850) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: z/OS-MVS Control Block Layout - Offsets
In a message dated 4/8/2008 9:32:53 A.M. Central Daylight Time, [EMAIL PROTECTED] writes: I'm more interested in the relationship between the blocks starting, obviously, at the PSA. I had a short document that told me what blocks were tagged off of what other blocks to help in running the chain. The data areas don't have this information, just what's in the blocks once you find them. There are hundreds of blocks, as you already know, since you have the books. Many years ago I saw a drawing of the interrelationships of many of the most important blocks in the control program, and it was close to looking like a bowl of spaghetti. Then there is the huge wall-size chart showing all of DB2's control block interrelationships. This same topic was discussed here within the last year, I think. Check the archives. Landmark Systems built a control block displaying/navigating tool into many of their monitors and also had a dump analyzer as a separate product. Check with Allen Systems if you are willing to pay $$ for this, otherwise use IPCS in a labor-intensive mode. I have no connection with Landmark/ASG any more. Bill Fairchild Rocket Software **Planning your summer road trip? Check out AOL Travel Guides. (http://travel.aol.com/travel-guide/united-states?ncid=aoltrv000316) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Long translate (TR) instruction?
In a message dated 3/24/2008 2:10:15 P.M. Central Daylight Time, [EMAIL PROTECTED] writes: Even if the z10 offered a Translate Extended instruction, the OP couldn't count on it being there on every Customer's machine for quite a while. The OP can use dual paths. If executing on machines without the newer instruction, then use TR; if the newer instruction is available, then use it. But don't put the test inside the loop. Nor is there any guarantee that IBM won't redesign the internals of whatever today is the fastest way to do something so that on a future processor it is slower, as in changing microcode into millicode. Bill Fairchild Rocket Software **Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15?ncid=aolhom000301) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SHARE no handouts(?)
In a message dated 3/1/2008 6:51:32 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Going Green is a euphemism for we want to save money by not providing copiers at the conference. SHARE does not discourage speakers from distributing paper handouts; it just doesn't want to incur the cost of printing them. IMO, going green was a convenient spin to justify the policy change. So the green does not mean eco-friendly but rather refers to the color of the FERNs [1] being saved? What about providing copiers that are not free? You copy your paper and pay for how many pages you copied. SHARE could still be non-profit if they computed the charge per page properly. Or instead of a copier there could be a page in the final agenda (is that still being printed? how much paper is wasted on that thing?) with directions to all the retail stores nearby which have pay-per-use copiers (Kinko's, e.g.). Bill Fairchild Rocket Software [1] FEderal Reserve Notes **Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp0030002598) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: 256 bytes again
In a message dated 2/25/2008 1:52:25 A.M. Central Standard Time, [EMAIL PROTECTED] writes: No. First - when you calculate number of blocks, you have to take into consideration many physical aspects of data storing, like Count field, gaps, data cell size, data cell existence, track size, R0, etc. I don't know TRKALC The hardware engineers who invent the new type of disk track, decide what its length will be, determine the size of the various gaps, produce the control unit microcode to implement and enforce these decisions, etc., provide a set of constants that can be plugged into generic formulas that are used by TRKCALC to calculate the effective size on the track of a new record (also called block by some) on that track and/or how many exactly like that will fit on the track. These constants are made available to the operating system by returning them in response to the Read Device Characteristics CCW command code, and the format of these constants is documented in the various control unit reference books. The operating system reads the device characteristics data when a DASD device is varied online. Also some of these constants are stored in the Format 4 DSCB (keyed record overhead, e.g.). The Format 4 DSCB also contains the number of DSCBs per track and the number of PDS directory blocks per track. These two values were computed based on the constants found in the device characteristics data. Typically, programmers do not need to concern themselves with these constants nor with the formulas for computing the effective size on the track of a block with key length X and data length Y. The formula has grown increasingly convoluted (my opinion) over the years as new device types have been devised. All a programmer usually needs to do is to set up the parameter list correctly and invoke the TRKCALC service. One way to see how many directory blocks fit on a track is to dump the Format 4 DSCB with AMASPZAP. Another way is to allocate a PDS with a large number of directory blocks and do an AMASPZAP dump of the first few tracks of the data set. You can then vary downwards the number of directory blocks to be allocated and see if there is also room on the track for an EOF record after the end of the directory or not, if you are interested in that. The bottom line is that a PDS directory block has had a constant key length of 8 and data area of 256 since day one of Version 1 of OS/360 back in the mid-1960s. The only variable has been how many fit on a track of each different DASD device type. The guy who precipitated all this extra discussion was trying to get the thread oriented to remembering that the key length must be considered when determining how many blocks will fit on the track. At least I think that was his intent. I also don't think that the thread had gone astray in that area, so I believe that this whole extra detailed discussion has been unnecessary and a molehill has been turned into a Mount Everest. The fact that two different IBM books describe the same entity or concept with slightly different terms does not necessarily mean that either of the books is incorrect. It means that they were written by different people, or perhaps by the same person at different times. Hardware-oriented people typically speak of a CKD thing that is recorded on a DASD track as a record, whereas software-oriented people typically speak of that same thing as a block. The term block size might be used by some in certain contexts to mean only the length of the data field of the CKD thing, or it might be used by some other people (or even by those same people in a different context) to mean the effective size on the track of the entire CKD thing, which would include the count field, the gap after the count field, the key field (if any), the gap after the key field (only present if there is a key field), the data field (if any), and the gap after the data field. So you are correct that the block size is 256. And that guy is also correct in saying that the block size is not 256. Both of you were thinking of different contexts when using the words block and size. The Using Data Sets book says PDS member entries ... are blocked into 256-byte blocks. If that is the only context you care about, then the block size is 256. But on that same page in the book is a diagram showing that the PDS Directory Block (the title of the diagram) has a count field and also an 8-byte key. So, according to this diagram, the key is part of the directory block. When you allocate a new PDS, you specify the number of directory blocks, and each such block, when written on the track, has an 8-byte key field in it. The term block size is used throughout many IBM books to mean only the length of the data field of a DASD CKD thing. But underlying all allocation concepts is the
Re: PDS dir block - 256 bytes
In a message dated 2/22/2008 4:25:25 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Recently I wrote that directory block has 256 bytes. Some responders claimed I was wrong. Given the voluminous amount of IBM documentation, you can often find several slightly differently worded phrases that describe the same entity. Depending on which one you read, remember, and use in a post, you may be unlucky enough not to use the same one that another poster remembers and will use as proof that you are wrong. In your case, the operative words were block and size. If you don't get every word perfect, you risk everything. It helps to have a thick skin when going public with our knowledge. Bill Fairchild Rocket Software **Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp0030002598) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SPAM: Re: COMPRESS QUESTION
In a message dated 2/18/2008 10:09:09 A.M. Central Standard Time, [EMAIL PROTECTED] writes: OK, I'll bite. A PDS directory block has an 8-byte count area, an 8-byte key area, and a 256-byte data area. Aha! When is a directory block not 256 bytes long? When 8 is not equal to 0. Which is why the number of directory blocks per 3390 track is what it is and not larger. I admit that you sucked me into your guessing game of wits once more. Since 8 is always not equal to 0, therefore a PDS directory block always has a data area that is not 256 bytes. Since this is impossible, I am now supposed to plead with you to reveal this latest conundrum of yours. You can explain in plain language what I am overlooking if you wish, but I give up on the guessing game. You win again, Seymour, as you always must. Oh please, please tell me the secret. Pretty please with sugar on top. Bill Fairchild An important art of politicians is to find new names for institutions which under old names have become odious to the people. [Talleyrand] **Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp0030002598) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SPAM: Re: COMPRESS QUESTION
In a message dated 2/18/2008 11:18:35 A.M. Central Standard Time, [EMAIL PROTECTED] writes: I THINK the difference arises because of the key. While many of us tend to ignore the key when referring to directory block, Seymour chooses NOT to ignore this value. I now see the source of the communications problem, which was exacerbated by Seymour's predilection to post one-word cryptic replies or, in the case of his reply to my post, a riddle. The poster wrote Just to clarify: size of dir. block is always 256 B. The meaning of the word size depends on whether you mean in virtual storage or stored on a disk track. In virtual storage, the size of a directory block is 272 bytes (count+key+data), as I described in my previous post. But if stored on a disk track, it depends on the device type but is always a lot more than 272, which Seymour had in mind but did not reveal to us. The word block might (correctly) mean to some the entire stored record (count+key+data) while (incorrectly) only the data area to others. This confusion has also not been helped by IBM documentation, which sometimes refers to a DASD block stored on a track as a block and at other times a record. Bill Fairchild **Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp0030002598) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SPAM: Re: COMPRESS QUESTION
In a message dated 2/14/2008 11:06:10 A.M. Central Standard Time, [EMAIL PROTECTED] writes: In 35+ years, I've never seen a directory block count stored anywhere; only the count of blocks used. The classic method of counting the total of directory blocks is to open the directory as a sequential dataset and read until EOF is encountered. I also have never seen the directory block count stored anywhere in a vani lla IBM system. Perhaps the poster was referring to a non-IBM use of some reserved field in the Format 1 DSCB. Also I have never heard of storing the count of blocks used anywhere. Where is this piece of data stored in vanilla IBM metadata? The Format 1 DSCB has a one-byte field for the number of bytes used in the last directory block and a 3-byte field for the TTR of the last used block in the entire data set. Perhaps you were thinking of one of those fields. The reason that a PDS directory entry that describes a load module is larger than a directory entry for other types of data is that load modules store info in the entry that is used by program fetch when the load module is being loaded. I don't remember the exact format of a directory entry, but there is at least one TTR stored in the entry as well as part of a byte telling how many halfwords of the directory entry are used for storing such data. Non-load modules have all these bytes containing zero. Some non-IBM products use this feature of a directory entry to store useful info, like date last used for the member. So non-load module entries will be larger than the mininum length (12 bytes, I think) if such software is installed and managing that PDS. There is a DSECT describing the directory entry somewhere in SYS1.MACLIB/MODGEN, I believe. Or maybe I saw this documented in a logic manual. Bill Fairchild Rocket Software The truth which makes men free is for the most part the truth which men prefer not to hear. [Jim Bishop; 1955; The Day Lincoln Was Shot] **The year's hottest artists on the red carpet at the Grammy Awards. Go to AOL Music. (http://music.aol.com/grammys?NCID=aolcmp0030002565) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: SPAM: Re: COMPRESS QUESTION
In a message dated 2/15/2008 3:07:03 P.M. Central Standard Time, [EMAIL PROTECTED] writes: Just to clarify: size of dir. block is always 256 B, No. OK, I'll bite. A PDS directory block has an 8-byte count area, an 8-byte key area, and a 256-byte data area. At the end of the directory is an end of file record, with a key length and data length both equal to zero. I would prefer not to equate this end of file record with a directory block. When is a directory block not 256 bytes long? Bill Fairchild Rocket Software The truth which makes men free is for the most part the truth which men prefer not to hear. [Jim Bishop; 1955; The Day Lincoln Was Shot] **The year's hottest artists on the red carpet at the Grammy Awards. Go to AOL Music. (http://music.aol.com/grammys?NCID=aolcmp0030002565) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Data Erasure Products
In a message dated 2/11/2008 3:00:22 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Unless I missed a part of the discussion, all statements that overwriting once is not good enough, were based on rumours, assumptions, theoretical possibilities and negative evidence (data is suggested to be readable until proven otherwise). If my video store says a video is not available and another store can deliver it, does this prove that all video stores that say a video is not available are lying? Is there some report, investigation, official statement to *prove* that overwriting once is not good enough? I am reminded of the epsilon-delta process that I learned in first semester college calculus. Good enough for what? You supply me with the for what and I'll provide you with the good enough. If the for what is that you want to sell a data erasure product to the United States Department of Defense, then you must fulfill their minimum requirements, for which there might theoretically be no provable basis in fact or experiment, but yet they published a requirement that said disk tracks must be overwritten six times in a row with specifically described, differing bit patterns. If you think that once is good enough, that may be ok for your needs, but you will not sell your erasure product to the DoD. The scientific explanation for what is going on at the atomic level is that when you record a one bit on a disk track you do not really write an entity called a bit on the track. You magnetize several billion atoms of iron and align them in a certain direction. When you read this bit back, the electronic mechanisms are designed to detect many kinds of errors in reading. One such error is that there is a weak signal (not strong enough for the electronics to call it a one or a zero). What should the electronics do in such a situation? One answer is to re-read the bit. Another is to move the read-write mechanism/transducer laterally an extremely small distance (called head shaking) and retry the read. The farther you move the read/write head away from the theoretical center of where the disk track is supposed to be, the more likely you are to detect magnetized alignment in some of the billions of atoms involved in storing a bit in the immediately adjacent track. Whenever you overwrite a bit, you remagnetize and realign the billions of atoms. But you can never realign 100 percent of them. There will always be a few that do not get realigned properly. The idea behind overwriting many times is that if you have sensitive enough equipment, you can theoretically filter out the 99% of the atoms that are correctly aligned and read only the 1% that are wrong. This may give you a clue as to what was previously written in that bit's location. If the value of the data is X dollars to your enterprise but 100 times X to your competition (or national enemy), then you need to spend a lot more than X dollars to make sure that your competition cannot read that data. The enemy may be willing to spend 50 times X dollars in research to build the world's most sensitive detector of magnetized atoms of iron or an extremely powerful microscope. Here is one Internet commentary on this subject: _http://www.nber.org/sys-admin/overwritten-data-guttman.html_ (http://www.nber.org/sys-admin/overwritten-data-guttman.html)He refutes the idea that overwritten data can be recovered by any method other than with a microscope. I would suggest that he did not have a Top Secret Compartmentalized clearance for this subject, and thus did not have access to the latest and greatest technology used by the National Security Agency, Central Intelligence Agency, and who knows what other black budget groups of the US government. Such information is not to be found in the public domain. They obviously know the answer, but they aren't telling. Since I don't have this kind of clearance either, I don't know for a fact what these agencies can do. But I did find the DoD's requirement in the public domain, and they want 6 successive overwrites of each track. That is their definition of good enough. Here is more information: _http://www.forensicswiki.org/wiki/Recovering_Overwritten_Data_ (http://www.forensicswiki.org/wiki/Recovering_Overwritten_Data) Here are some comments lifted from a blog: (1) while it may be possible to remove data in layers and recover older data that was in its space before, no commercial data recovery company offers this service. (The german computer magazin c't tried to get data recoverd that was overwritten once some time ago. All data-recovery outfits they contacted said they could not do this.) It might be impossible to actually do this, e.g. because the overwritten signal is too close to the noise-level. It used to be possible with older HDD technology, that did not use the magnetic
Re: VTOC size
In a message dated 2/9/2008 5:34:12 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Mate, you have to update your disk drive knowledge a bit. It's been a long time since a single 56664 track would fit on 3.5 inch disk. ... largest track size can be estimated as ... nearly a full CKD CYL in a single track. You're right. I was assuming that one RAID track holds only one emulated 3390 track. in most cases the backend pre-fetch can stay ahead of a single threaded sequential read. And having unlimited CCW prefetch now as an option in the LPAR helps get multiple tracks' data into central storage faster than single threading. I think it is a long time since backups operated as single track IO. I didn't mean to imply they only read one track per I/O. I meant they read the volume sequentially. They can chain up 1,000 tracks per I/O request if they want and if they have enough real storage. But they still go through the whole volume sequentially. The first such I/O reads tracks 0-999 while maybe a second buffer is reading in tracks 1000-1999. When 0-999 are written to tape, tracks 2000-2999 start being read (if BUFNO is only 2). Etc. Multiple tracks per I/O, but still reading sequentially through the volume with only one process (task) that may be doing multiple simultaneous channel programs (as in SAME's BUFNO1). With BUFNO=huge you would not to have multiple tasks copying different parts of the volume simultaneously. At one cylinder per BUFNO, you could get 100 such I/Os running together with a mere 150MB of real storage tied up (75 for DASD in and another 75 for tape out). That's not very much real these days. A shop with really huge volumes is also likely to have a really huge amount of central storage. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: VTOC size
In a message dated 2/8/2008 3:45:21 P.M. Central Standard Time, [EMAIL PROTECTED] writes: On FICON it would be reasonable to expect to get 50MB/sec to and from your Disk and tape drives. ... So 54,000MB at 50MB/sec is 1080 seconds, or 18 minutes. I may be wrong, but I think backup/archive/retrieval/migrate products that are operating on a whole volume level do each track serially, so a backup of a really huge volume would be limited by the slowest part of the I/O path which I believe will be the rotation speed of the disks. No matter how big the controller's cache is, sooner or later a backup of an entire really huge volume is going to slow down to match the track rotational speed. The SLED 3390 rotated at 70 RPS, which at 57K per track yielded about 4MB/second. RAID disks rotate a lot faster than the 3390 did, but I think it's on the order of twice the RPS rather than 10 to 20 times as fast. I would expect that a controller could not cram more than 10MB per second into that 50MB FICON channel unless the backup product is doing some kind of multitasking or similar operation whereby it can do multiple large-scale reads at the same time. There's no other way to break the rotation barrier. Do backup products work like that yet? 54000 MB at 10MB/second = 5400 seconds = 90 minutes. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Data Erasure Products
In a message dated 2/7/2008 12:27:49 A.M. Central Standard Time, [EMAIL PROTECTED] writes: I believe someone on here said that the DOD said 15 writes over the data set was good enough. The latest (JUN 2001) DOD specification that I read on the Internet said six times is enough, but you have to write certain bit patterns. The German DOD wants seven times. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: What happened to resumable instructions?
In a message dated 2/3/2008 10:30:37 A.M. Central Standard Time, [EMAIL PROTECTED] writes: How are page faults handled for resumable instructions? Is a fault generated for any page in the range of either operand, with the OS attempting to stage both I haven't had the need to study a system trace in which both sets of operands were non-zero, but I have seen the results of a MVCL that clears storage with a second operand of zero length. There is a page fault traced for every 4K in the slab of storage being cleared. The translation exception address that shows up in the trace increases by X'1000' in each such traced page fault. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trouble opening specific volumes with OPEN TYPE=J
In a message dated 2/4/2008 11:54:44 A.M. Central Standard Time, [EMAIL PROTECTED] writes: The reason that you need to is that when using EXCP or BSAM, then OPEN only gives you access to one volume at a time. ... etc. ... etc. I have never done an EXTEND or altered the volume sequence number in the JFCB, which I now recollect is what you are doing, so my comments do not fit your situation. Sorry for the confusion. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Trouble opening specific volumes with OPEN TYPE=J
In a message dated 2/4/2008 9:32:48 A.M. Central Standard Time, [EMAIL PROTECTED] writes: I'm trying to read a dataset that will potentially have many volumes each of which has up to 16 extents. I'm trying to open the dataset in a way that I get one volume at a time, with the DEB reflecting the extents of that volume. I don't know how to open the data set in such a way, nor do I see why you need to do so. Suppose there are 16 volumes in the data set and each volume has 16 extents. Your DCB has a DDNAME=WHATEVER. Your DD statement for WHATEVER points to the data set name. You OPEN the DCB. Your DEB that will be constructed has 256 extent entries in it, with the first 16 pointing to the UCB for the first of the 16 volumes, the second set of 16 extent entries in the DEB all point to the UCB for the second of the 16 volumes, etc. You use EXCP to read this file. You construct your own MBBCCHHR in the IOB before doing the EXCP. You can put any value you want into the M byte. If you put a value between X'00' and X'0F' you will use one of the first 16 extent entries in the DEB and thus access volume 1. Etc. Whenever you want to go from volume(n) to volume(N+1) you will need a new M value, as also you will if you move from extent(x) to extent(x+1) within the same volume. What you're talking about sounds like BDAM where you get a single logical view of a multivolume dataset? The access method is irrelevant. You will get the same kind of multi-extent DEB whether you use EXCP, XDAP, BDAM, BSAM , QSAM, BISAM, QISAM, or BPAM. I'm wanting to do EXCP access and my understanding is that when you do this you get a simple DCB which is connected to one volume at a time and for which the DEB just reflects however many extents are on that volume. Certainly this is what I see, and this is how I'm performing my I/O. I don't know where you see this, because this is not what you get. You get a simple DCB, whatever that means, that is connected to (points to) a single complex DEB (I just made up the descriptor complex) that points to ALL the extents in the file regardless of the volume involved. Create a multi-volume file, OPEN a simple DCB to it, ABEND, and study the construction of the DEB, not the DCB. Bill Fairchild Rocket Software **Biggest Grammy Award surprises of all time on AOL Music. (http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp00300025 48) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
NDAs (was New Opcodes)
In a message dated 1/28/2008 5:59:24 A.M. Central Standard Time, [EMAIL PROTECTED] writes: Anyone who knows about this stuff can't discuss it... I have been privy to many documents under Non-Disclosure Agreement over the years. As far as I can remember, only once did I read and sign the entire legal document governing the NDA. All the other times a manager or some other colleague of mine told me that the document was under NDA. I do not know if a standard NDA contains language prohibiting discussing even the fact that one has seen the NDA, let alone the document(s) revealed. But to discuss the fact that one has seen a document, or even the NDA itself, to me seems like a question that must be asked of one's manager if one has a burning desire to reveal that fact. Someone in the organization has read, understands, and remembers all the legal fine print, and it likely not to be one's immediate manager. The manager will almost certainly say that one should not even mention having seen the document. It is preferable to err on the side of caution in such matters. Without having access to the NDA and then being given access to a document under the NDA, I would have to assume that I should not discuss anything regarding the NDA itself or the document(s) with anyone other than colleagues, and then only if they have been made aware of the NDA nature of the document. Bill Fairchild Rocket Software **Start the year off right. Easy ways to stay in shape. http://body.aol.com/fitness/winter-exercise?NCID=aolcmp0030002489 -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: CFW with Syncsort
In a message dated 1/21/2008 10:39:36 A.M. Central Standard Time, [EMAIL PROTECTED] writes: It looks like the GDPS group also misunderstood CFW. ... Excerpt from GDPS You should eliminate any known exploitation of Cache Fast Write (CFW). Disk write operations using CFW (Cache Fast Write) are written into cache but not to the disk. Having CFW operations in progress at the time a HyperSwap occurs can yield unpredictable results since there is no corresponding mirrored cache content in the secondary disk subsystem. Any known exploiters of CFW (such as DFSORT) should be customized to not use CFW. It looks to me rather that the GDPS group did not misunderstand CFW, since they are saying not to use CFW with GDPS, then they explain why not, and in their explanation they offer what looks like a correct understanding of CFW. GDPS uses PPRC to keep a secondary volume in synch with a primary volume. When data is written to a primary PPRC volume, the primary controller writes the data into its (primary) cache, sends the data down the communications link to the secondary volume's controller which then writes that data into its (the secondary's) cache, sends a signal back to the primary controller that the data is now safely in the secondary's cache, and then and only then will the primary controller signal that the I/O request on the primary LPAR is complete. (The order of the first two operations I described above could be reversed without affecting the final outcome, namely that the primary I/O is not deemed complete until the secondary is known to have a valid copy of the data. But it may well be that the controller does both of these operations simultaneously for performance reasons. I don't know that detail. And in fact the controller should, in my opinion, start writing the data to the comm link before writing it into its cache, since the comm link operation could take a much longer time to complete than the cache operation if the secondary's distance is great enough.) The designers of the PPRC microcode could have chosen to support CFW operations on a primary PPRC I/O request, but evidently decided not to. They documented this somewhere, and the GDPS group were able to find it and write a warning not to use CFW on a PPRC primary. The purpose of CFW data is for easily recreatable, intermediate data that almost never really needs to be made permanent. Sort work files are an excellent example of CFW data. I don't see why anything bad could happen if you allow CFW data onto a PPRC primary, since presumably the CFW is easily recreatable. And you probably would not want to send such data down a communications link anyway. I am here speaking of normal operations. When Hyperswap gets involved, there is an abnormal operation underway. I suspect the warning against CFW on a PPRC primary is self-defensive overkill on the part of the GDPS lawyers. Bill Fairchild Franklin, TN **Start the year off right. Easy ways to stay in shape. http://body.aol.com/fitness/winter-exercise?NCID=aolcmp0030002489 -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: CFW with Syncsort
In a message dated 1/18/2008 8:52:20 P.M. Central Standard Time, [EMAIL PROTECTED] writes: Yes, SyncSort does use CFW. I wrote the code myself in a previous life, 17 or so years ago. However, IIRC, there may be circumstances where it is turned off due to other performance considerations. Check with SyncSort's Customer Service if you need to know when, if ever these days. They may not choose to reveal such info. If the need to know is great enough, one can always trace Syncsort for a while with GTF and study the channel programs. Then the real fun begins - perusing the formatted GTF trace records (not for the impatient or faint of heart). Bill Fairchild Franklin, TN **Start the year off right. Easy ways to stay in shape. http://body.aol.com/fitness/winter-exercise?NCID=aolcmp0030002489 -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
