Re: Definition of mainframe? Was: Ars Technica
> On Tuesday, August 1, 2023 at 07:59:07 AM PDT, Grant Taylor wrote: >> On 8/1/23 2:49 AM, Colin Paice wrote: >> You can have synchronous write - used in same "site" and async - >> where the remote end is miles away. This is used for media failure. > Yes. Emphasis on /media/ failure. This does nothing for /data/ > failure, e.g. corruption / malicious activity. > Traditional offline backups address both /media/ failure and /data/ failure. > Note. This is not a backup. If you delete the dataset, both copies will be > deleted. > I usually see snapshots created a couple of different ways: > 1) The older way was to pause things and take an actual copy. Tunnel vision is the biggest problem people need to address. IBM GDPS is decades old and has always included an IBM services contract to specifically address customer tunnel vision. They start with a big picture approach by first identifying the recovery requirements and recovery problems that must be addressed. Only at that point can you then decide the software, hardware and procedural components to best meet the requirements and solve the problems. To say "This is not a backup" ignores the stated requirements (delete a file and have a backup). Rename resolves both requirements. To say "async - where the remote end is miles away" denies the existence of GDPS. As in the name implies, Globally Dispersed Parallel Sysplex, you can have a sysplex split between 2 active locations. Sync is a sysplex requirement. To say "usually see snapshots" ignores requirements. A GDPS customer will have many requirements and money is usually lowest on the list (or not on the list). Consider for instance, a dual copy disk on both sites of the sysplex and each disk is mirrored (2 disks on at each site). When all commits have completed, turn off mirroring at one site and you have a moment in time backup, site failure recovery if the unmirrored disk fails and site failure recovery if the mirrored disk site fails. Recovery is far more complicated than a single component. There is substance to everything being said but realize this is a truth, but not necessarily the complete truth. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Williams tube: periodic regeneration Drum: stable Delay line: amplification Core, rod, thin film: destructive read followed by rewrite From: IBM Mainframe Discussion List on behalf of Mike Schwab Sent: Tuesday, August 1, 2023 12:24 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Definition of mainframe? Was: Ars Technica I think most pre- semiconductor memory including core memory in S/360 was destructive reads with hardware rewiting the store, so you can certainly understand using move, not to mention C for Compare instructions had few alternatives. On Tue, Aug 1, 2023, 10:51 Seymour J Metz wrote: > The term of art "move" goes back at least to the 705, well before COBOL, > so even if it's confusing it's not likely to change. > > > From: IBM Mainframe Discussion List on behalf > of Gary Weinhold > Sent: Tuesday, August 1, 2023 11:38 AM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Re: Definition of mainframe? Was: Ars Technica > > >> Wayne B wrote: > COBOL MOVE was not intuitive. Should have been PROPOGATE or COPY, COPY was > already taken I guess. > > > Assembler has the same problem: MVC, MVCL, etc. > > > > Gary Weinhold > Senior Application Architect > DATAKINETICS | Data Performance & Optimization > Phone:+1.613.523.5500 x216 > Email: weinh...@dkl.com > Visit us online at http://www.dkl.com/ > E-mail Notification: The information contained in this email and any > attachments is confidential and may be subject to copyright or other > intellectual property protection. If you are not the intended recipient, > you are not authorized to use or disclose this information, and we request > that you notify us by reply mail or telephone and delete the original > message from your mail system. > > > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
I think most pre- semiconductor memory including core memory in S/360 was destructive reads with hardware rewiting the store, so you can certainly understand using move, not to mention C for Compare instructions had few alternatives. On Tue, Aug 1, 2023, 10:51 Seymour J Metz wrote: > The term of art "move" goes back at least to the 705, well before COBOL, > so even if it's confusing it's not likely to change. > > > From: IBM Mainframe Discussion List on behalf > of Gary Weinhold > Sent: Tuesday, August 1, 2023 11:38 AM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Re: Definition of mainframe? Was: Ars Technica > > >> Wayne B wrote: > COBOL MOVE was not intuitive. Should have been PROPOGATE or COPY, COPY was > already taken I guess. > > > Assembler has the same problem: MVC, MVCL, etc. > > > > Gary Weinhold > Senior Application Architect > DATAKINETICS | Data Performance & Optimization > Phone:+1.613.523.5500 x216 > Email: weinh...@dkl.com > Visit us online at http://www.dkl.com/ > E-mail Notification: The information contained in this email and any > attachments is confidential and may be subject to copyright or other > intellectual property protection. If you are not the intended recipient, > you are not authorized to use or disclose this information, and we request > that you notify us by reply mail or telephone and delete the original > message from your mail system. > > > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
The term of art "move" goes back at least to the 705, well before COBOL, so even if it's confusing it's not likely to change. From: IBM Mainframe Discussion List on behalf of Gary Weinhold Sent: Tuesday, August 1, 2023 11:38 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Definition of mainframe? Was: Ars Technica >> Wayne B wrote: COBOL MOVE was not intuitive. Should have been PROPOGATE or COPY, COPY was already taken I guess. Assembler has the same problem: MVC, MVCL, etc. Gary Weinhold Senior Application Architect DATAKINETICS | Data Performance & Optimization Phone:+1.613.523.5500 x216 Email: weinh...@dkl.com Visit us online at http://www.dkl.com/ E-mail Notification: The information contained in this email and any attachments is confidential and may be subject to copyright or other intellectual property protection. If you are not the intended recipient, you are not authorized to use or disclose this information, and we request that you notify us by reply mail or telephone and delete the original message from your mail system. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
>> Wayne B wrote: COBOL MOVE was not intuitive. Should have been PROPOGATE or COPY, COPY was already taken I guess. Assembler has the same problem: MVC, MVCL, etc. Gary Weinhold Senior Application Architect DATAKINETICS | Data Performance & Optimization Phone:+1.613.523.5500 x216 Email: weinh...@dkl.com Visit us online at www.DKL.com E-mail Notification: The information contained in this email and any attachments is confidential and may be subject to copyright or other intellectual property protection. If you are not the intended recipient, you are not authorized to use or disclose this information, and we request that you notify us by reply mail or telephone and delete the original message from your mail system. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 8/1/23 2:49 AM, Colin Paice wrote: Your Copy on Write - may be what I know as dual write - where you write to different volumes - usually on different dasd subsystems, so if you lose one dasd subsystem - the data is available on another. Nope. "Copy on Write" is explicitly what you were previously describing where in multiple references to the data had the same singular copy of the data in the back-end and and things are copied only when one of the references to the data changes the data. As long as COW instances use the exact same data, as in base OS data sets from the same OS version, then there's only the single instance, independent of how many references to it there are. I see writing to multiple drives in parallel -- from an OS / software level -- referred to as software RAID / mirroring. COW and RAID (mirroring) are different things meant to serve different purposes. You can have synchronous write - used in same "site" and async - where the remote end is miles away. This is used for media failure. Yes. Emphasis on /media/ failure. This does nothing for /data/ failure, e.g. corruption / malicious activity. Traditional offline backups address both /media/ failure and /data/ failure. Note. This is not a backup. If you delete the dataset, both copies will be deleted. needMOREcoffee We seem to be thinking very similar things but typing at different times. I was talking about what I think is called snapshot. It is used like 1- Issue Snapshot copy (of your database) - this takes a couple of seconds or less. I usually see snapshots created a couple of different ways: 1) The older way was to pause things and take an actual copy. This was slower and took quite a while O(minutes ~> hours). 2) The newer way seems to be some sort of -- what I would call -- COW system where changes to parts of the storage are written to a new location and access to the primary / live interface reflect the new data. Conversely the snapshot interface reflects the old data from the point in time the snapshot was made. This is faster and takes much less time O(seconds). The gory details of how it's done are implementation specific. 2- Backup this copy - it may take a couple of hours to read from the DASD subsystem, and write to perhaps Virtual Tape. Agreed. 3- The original data set continues to be updated, whereas the copy does not change, so you have point of time consistency Agreed. 4- You can restore to the point of time, and for products like DB2 and MQ, read the logs and reapply all of the updates. I think I agree though I will say that depending on how the snapshot was taken and if the higher level applications are aware of the snapshot and quiesced in support of the snapshot may make the difference between a "crash consistent" snapshot / copy and a "suspend consistent" snapshot. This type of consistency and how the applications roll forward here from gets interesting and tricky. But, even a crash consistency snapshot is almost always more current and easier to recover than a cold backup from hours / days ago. Or at least looses less data / is more fresh / less effort to bring back current. Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Your Copy on Write - may be what I know as dual write - where you write to different volumes - usually on different dasd subsystems, so if you lose one dasd subsystem - the data is available on another. You can have synchronous write - used in same "site" and async - where the remote end is miles away. This is used for media failure. Note. This is not a backup. If you delete the dataset, both copies will be deleted. I was talking about what I think is called snapshot. It is used like 1- Issue Snapshot copy (of your database) - this takes a couple of seconds or less. 2- Backup this copy - it may take a couple of hours to read from the DASD subsystem, and write to perhaps Virtual Tape. 3- The original data set continues to be updated, whereas the copy does not change, so you have point of time consistency 4- You can restore to the point of time, and for products like DB2 and MQ, read the logs and reapply all of the updates. On Tue, 1 Aug 2023 at 03:06, Grant Taylor < 023065957af1-dmarc-requ...@listserv.ua.edu> wrote: > On 7/31/23 12:45 PM, Colin Paice wrote: > > A volume is a convenient picture - they no longer exist on modern DASD. > > ACK > > My limited understanding is that the S/360 or S/370 would probably not > recognize anything in use today as DASD. The S/390 /might/ see > something that vaguely reminds it of DASD through ESCON / FICON. > > It seems as if things are significant numbers of layers of abstraction > and emulation. > > > Data is spread across many different PC sized disks. > > Yep. > > It's amazing if not mind blowing what can be done with abstraction and > virtualization of storage. > > > We have extended volumes which are bigger than traditional volumes. > > It gives more space for the same number of volumes. > > :-) > > > A "track" is mapped to one PC sized disk, and block on disk.. > > If you rewrite a track it will most probably go to a different > > PC disk. In the storage controller there is a big array which has > > VOLID.CYL.Track -> pcdisk.position. > > I'm not unpacking and scrutinizing that based on your "Some of the above > is not true" comment. > > > I can "copy a dataset" on the same DASD subsystem just by copying > > the relevant bits of this array. So if we have part of dataset1 > > USER00.00.01 -> PCDISK1. 4000 the copy creates USER99.4002.12 -> > > PCDISK1.4000. This copy takes a second or so. There is no data > > transfer. If you update dataset1, then its VOLID.CYL.track will > > point to a new block, and so the arrays diverge. > > This sounds like what I generally hear referred to as "copy on write" > and is frequent enough that it's abbreviated as C.O.W. and multiple > things support this, one even with COW in the file name. > > > If we copy the dataset to a different DASD subsystem - then every block > > will be read - and written to the other subsystem. > > Yep. > > > Some of the above is not true - but it gives the picture. > > ;-) > > > > Grant. . . . > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Mostly the same CCW opcodes. ECKD added some and a few obsolete ones are gone. Of course, FBA and FCP are new. Physical volumes are another matter - he's dead, Jim. From: IBM Mainframe Discussion List on behalf of Grant Taylor <023065957af1-dmarc-requ...@listserv.ua.edu> Sent: Monday, July 31, 2023 10:05 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Definition of mainframe? Was: Ars Technica On 7/31/23 12:45 PM, Colin Paice wrote: > A volume is a convenient picture - they no longer exist on modern DASD. ACK My limited understanding is that the S/360 or S/370 would probably not recognize anything in use today as DASD. The S/390 /might/ see something that vaguely reminds it of DASD through ESCON / FICON. It seems as if things are significant numbers of layers of abstraction and emulation. > Data is spread across many different PC sized disks. Yep. It's amazing if not mind blowing what can be done with abstraction and virtualization of storage. > We have extended volumes which are bigger than traditional volumes. > It gives more space for the same number of volumes. :-) > A "track" is mapped to one PC sized disk, and block on disk.. > If you rewrite a track it will most probably go to a different > PC disk. In the storage controller there is a big array which has > VOLID.CYL.Track -> pcdisk.position. I'm not unpacking and scrutinizing that based on your "Some of the above is not true" comment. > I can "copy a dataset" on the same DASD subsystem just by copying > the relevant bits of this array. So if we have part of dataset1 > USER00.00.01 -> PCDISK1. 4000 the copy creates USER99.4002.12 -> > PCDISK1.4000. This copy takes a second or so. There is no data > transfer. If you update dataset1, then its VOLID.CYL.track will > point to a new block, and so the arrays diverge. This sounds like what I generally hear referred to as "copy on write" and is frequent enough that it's abbreviated as C.O.W. and multiple things support this, one even with COW in the file name. > If we copy the dataset to a different DASD subsystem - then every block > will be read - and written to the other subsystem. Yep. > Some of the above is not true - but it gives the picture. ;-) Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/31/23 12:45 PM, Colin Paice wrote: A volume is a convenient picture - they no longer exist on modern DASD. ACK My limited understanding is that the S/360 or S/370 would probably not recognize anything in use today as DASD. The S/390 /might/ see something that vaguely reminds it of DASD through ESCON / FICON. It seems as if things are significant numbers of layers of abstraction and emulation. Data is spread across many different PC sized disks. Yep. It's amazing if not mind blowing what can be done with abstraction and virtualization of storage. We have extended volumes which are bigger than traditional volumes. It gives more space for the same number of volumes. :-) A "track" is mapped to one PC sized disk, and block on disk.. If you rewrite a track it will most probably go to a different PC disk. In the storage controller there is a big array which has VOLID.CYL.Track -> pcdisk.position. I'm not unpacking and scrutinizing that based on your "Some of the above is not true" comment. I can "copy a dataset" on the same DASD subsystem just by copying the relevant bits of this array. So if we have part of dataset1 USER00.00.01 -> PCDISK1. 4000 the copy creates USER99.4002.12 -> PCDISK1.4000. This copy takes a second or so. There is no data transfer. If you update dataset1, then its VOLID.CYL.track will point to a new block, and so the arrays diverge. This sounds like what I generally hear referred to as "copy on write" and is frequent enough that it's abbreviated as C.O.W. and multiple things support this, one even with COW in the file name. If we copy the dataset to a different DASD subsystem - then every block will be read - and written to the other subsystem. Yep. Some of the above is not true - but it gives the picture. ;-) Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 1/08/2023 12:16 am, Rick Troth wrote: But, again, an automount per user does not necessarily mean a filesystem per user. Agree... but I was specifically talking about a filesystem per user as a bad thing. This seems to have become a common thing on z/OS. -- Andrew Rowley Black Hill Software -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Our site had 3,000 mostly M9s totaling 30 TB. 4 Ess f20 consolidated to two Ess 800 then 1 EMC Max when I retired. On Mon, Jul 31, 2023, 10:46 Grant Taylor < 023065957af1-dmarc-requ...@listserv.ua.edu> wrote: > On 7/31/23 6:37 AM, Jay Maynard wrote: > > It's not just CPU power or number of cores, but the ability to connect > > thousands of volumes of data and access them simultaneously, and move > > that data from point A to point B efficiently. > > Please elaborate, are those volumes separate DASD devices or are they > possibly some logical component thereon? > > I also wonder how common it is to have four digits of volumes (physical > or logical) varied on at the same time. > > I wonder this about both mainframes and some of the largest Open Systems > that I've been exposed to. > > Hundreds absolutely happens. I don't know about a thousand or more. > > Also, what constitutes a volume? How different are FCP and FC LUNs? > How different are they when the same back end storage system is > exporting LUNs to both mainframe and Open Systems, with the primary > difference being FCP vs traditional FC? > > > > -- > Grant. . . . > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
A volume is a convenient picture - they no longer exist on modern DASD. Data is spread across many different PC sized disks. We have extended volumes which are bigger than traditional volumes. It gives more space for the same number of volumes. A "track" is mapped to one PC sized disk, and block on disk.. If you rewrite a track it will most probably go to a different PC disk. In the storage controller there is a big array which has VOLID.CYL.Track -> pcdisk.position. I can "copy a dataset" on the same DASD subsystem just by copying the relevant bits of this array. So if we have part of dataset1 USER00.00.01 -> PCDISK1. 4000 the copy creates USER99.4002.12 -> PCDISK1.4000. This copy takes a second or so. There is no data transfer. If you update dataset1, then its VOLID.CYL.track will point to a new block, and so the arrays diverge. If we copy the dataset to a different DASD subsystem - then every block will be read - and written to the other subsystem. Some of the above is not true - but it gives the picture. Colin On Mon, 31 Jul 2023 at 16:46, Grant Taylor < 023065957af1-dmarc-requ...@listserv.ua.edu> wrote: > On 7/31/23 6:37 AM, Jay Maynard wrote: > > It's not just CPU power or number of cores, but the ability to connect > > thousands of volumes of data and access them simultaneously, and move > > that data from point A to point B efficiently. > > Please elaborate, are those volumes separate DASD devices or are they > possibly some logical component thereon? > > I also wonder how common it is to have four digits of volumes (physical > or logical) varied on at the same time. > > I wonder this about both mainframes and some of the largest Open Systems > that I've been exposed to. > > Hundreds absolutely happens. I don't know about a thousand or more. > > Also, what constitutes a volume? How different are FCP and FC LUNs? > How different are they when the same back end storage system is > exporting LUNs to both mainframe and Open Systems, with the primary > difference being FCP vs traditional FC? > > > > -- > Grant. . . . > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/31/23 9:28 AM, Schmitt, Michael wrote: MAINFRAME: a computer that is larger than a midrange minicomputer and smaller than a supercomputer. Chuckle. pc < workstation < minicomputer < mainframe < supercomputer I posit that we should word smith to be "single computer" to rule out large Google sized clusters of thousands of computers. But if we rule out "single computer" how does that effect sysplex / CF? If we say that sysplex / CF is a single computer, does that mean that we also include NUMA servers from the '90s which appeared to run a single system image? Definitions get tricky and require discussion back and forth to arrive at a common definition accepted for the conversation at hand. More seriously, http://catb.org/jargon/html/M/mainframe.html refers to http://catb.org/jargon/html/D/dinosaur.html, which is defined as "Any hardware requiring raised flooring and special power." LOL That tends to put mains and supers in the same category. At least most of them. It might have included some mini's in the days of yore. Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/31/23 6:37 AM, Jay Maynard wrote: It's not just CPU power or number of cores, but the ability to connect thousands of volumes of data and access them simultaneously, and move that data from point A to point B efficiently. Please elaborate, are those volumes separate DASD devices or are they possibly some logical component thereon? I also wonder how common it is to have four digits of volumes (physical or logical) varied on at the same time. I wonder this about both mainframes and some of the largest Open Systems that I've been exposed to. Hundreds absolutely happens. I don't know about a thousand or more. Also, what constitutes a volume? How different are FCP and FC LUNs? How different are they when the same back end storage system is exporting LUNs to both mainframe and Open Systems, with the primary difference being FCP vs traditional FC? -- Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
MAINFRAME: a computer that is larger than a midrange minicomputer and smaller than a supercomputer. More seriously, http://catb.org/jargon/html/M/mainframe.html refers to http://catb.org/jargon/html/D/dinosaur.html, which is defined as "Any hardware requiring raised flooring and special power." -Original Message- From: IBM Mainframe Discussion List On Behalf Of Jon Perryman Sent: Saturday, July 29, 2023 11:28 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Definition of mainframe? Was: Ars Technica Can anyone provide the definition of MAINFRAME? The ARS Technica article is complete nonsense because the mainframe is a state of mind and nothing to do with reality. Can anyone prove me wrong? https://arstechnica.com/information-technology/2023/07/the-ibm-mainframe-how-it-runs-and-why-it-survives/. The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I suspect it still uses a PCIe zCPU card. I can't say with any certainty, but I suspect that z/OS will run on a PC by using Hercules. What is the definition of MAINFRAME? 1. CPU does not make a mainframe: The smallest IBM z16 (39 user cores of the 64 cores) is the same as an AMD Ryzen 4.2Ghz CPU (64 user cores of 64 cores). The largest IBM z16 (200 user cores of the 256 cores) is the same as 4 AMD Ryzen CPU on 1 motherboard (256 user cores of the 256 cores). Both are CISC CPU (AMD uses X86 instructions versus IBM z instructions). IBM Telum (5.2Ghz) has a slightly faster clock than AMD Ryzen (4.2Ghz) but is offset by the 25% extra user cores. IBM z16 has 4 motherboards for 16 CPU and the same AMD Ryzen would need 1 motherboard for 4 CPU. 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also on every modern motherboard. IBM z16 chooses not to include other hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was enough customer demand. 3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. IBM hasn't duplicated z/OS software features in Linux. 4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for z/OS. DB2 for Linux runs on all hardware including z16. With Linux, you can still run DB2 on z16 but large customers choose DB2 for z/OS. ASK YOURSELF: Other than design philosophy, name 1 fundamental difference between IBM z16, AMD Ryzen and the software. ASK YOURSELF: Since design philosophy is the only difference, name the philosophy that makes a mainframe. Despite the story's false claims for z/OS relevance, it is ignorance in the Linux community that makes IBM z/OS relevant. Specifically, it's the lack of design in Linux. Consider DB2 for Linux and DB2 for z/OS which are the same product both from IBM and available on an IBM z16. Linux people tell you they provide the same results, but they ignore the intrinsic capabilities of z/OS design. DB2 for Linux supports high availability and large databases but it requires knowledge of big data solutions, Linux clustering solutions and more. Add a computer to the cluster and you must replicate the master disk. Take a computer offline from the cluster, then it must re-sync or replicate the master disk. DB2 on z/OS does not experience these problems because of z/OS shared dasd and dasd mirroring. ASK YOURSELF: Name 1 brilliant feature design that originated directly from Linux or Unix. Please don't use features that originated from IBM (e.g. databases, SQL, HTML, Cloud and more). Brilliant feature design exposes very little. For instance, does anyone know the problems solved by z/OS shared dasd and dasd mirroring. Linux people on the other hand can easily name those problems solved if you mention clustering solutions and big data solutions. I've personally seen one sysplex split between 2 sites 40 KM apart using line of site satellite dishes for communication, yet z/OS app programmers were informed. In other words, IBM designs for the 21st century. ASK YOURSELF: Name 1 brilliant unnoticed Linux feature. Name several brilliant unnoticed z/OS features. The story claims Linux feature design is similar to z/OS feature design. For example, the story claims Unix filesystems provide the same functionality as z/OS datasets. A filesystem is the equivalent of one PDS/e (even in Linux). In fact, z/OS Unix filesystems were built from PDS/e functionality. A filesystem is a container file containing the files in a Unix filesystem. You may have a filesystem using 10 disks but that's not any different than a single z/OS PDS/e file with 10 full disk extents. Like PDS/e
Re: Definition of mainframe? Was: Ars Technica
On 7/31/23 09:09, Dave Jones wrote: Opps.I was wrong. According to this site (https://en.wikipedia.org/wiki/CERN_httpd), the first web server at CERN was indeed written and hosted on a NeXT Computer running NeXTSTEP. I must have dreamed the part about VM, then. Thanks for clarifying. I also recall CERN running a web server on VM at that time. I know that they had a major VM installation. (And mainframes counted as supercomputers in those days, which would have been very relevant to CERN.) DJ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- R; <>< -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/30/23 18:50, Andrew Rowley wrote: On 30/07/2023 2:28 am, Jon Perryman wrote: ASK YOURSELF: Name the z/OS Unix feature that sort of fixes the fundamental design flaw with Unix filesystems just described? I suspect most people won't think about each user having a unique filesystem using automount to make their filesystem available. Typical Unix uses one file system with all users having directories in the /user directory. An automounted filesystem per user has always been a terrible idea. I think it was given as an example of how you could use automount and somehow morphed into a recommendation. (Other OSes can e.g. use automount to mount a remote user filesystem via NFS). I responded to this in a thread fork. The points Andrew makes are sound, but there's context where per-user automount is a GOOD idea. Reasons it's a bad idea: 1) Freespace in the filesystem is not shared between users. This means that you need much more space than if there was one pool of freespace shared between all. (repeating) if the thing mounted is a sub-dir of a shared space, this argument is void. 2) It makes simple questions like e.g. "Which users have a .ssh/authorized_keys file?" much harder to answer. Certainly. But it also means that ~.ssh/authorized_keys follows the user, which is beneficial. A filesystem per user is basically equivalent to a SMS storage group and catalog per user. You get isolation between users, but at the expense of much more difficult management. But, again, an automount per user does not necessarily mean a filesystem per user. -- R; <>< -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Opps.I was wrong. According to this site (https://en.wikipedia.org/wiki/CERN_httpd), the first web server at CERN was indeed written and hosted on a NeXT Computer running NeXTSTEP. I must have dreamed the part about VM, then. DJ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
To me, mainframe denotes one large computer that is expandable to handle volumes of tasks and data that require hundreds if not thousands of PC-class systems to handle, with an emphasis on reliability, availability, and serviceability. It's not just CPU power or number of cores, but the ability to connect thousands of volumes of data and access them simultaneously, and move that data from point A to point B efficiently. It's also a mindset: instead of "just reboot it", RAS demands an effort be made to find the cause of every problem and fix it. Yes, it needs specialized skills and tools, but then so does that datacenter that PC types say "oh, just slide another rack row of blade servers in" about. There are jobs mainframes do well, and that's why there are still so many in service. On Mon, Jul 31, 2023 at 5:41 AM P H < 04843e86df79-dmarc-requ...@listserv.ua.edu> wrote: > IBM's definition of mainframe (Source: DICTIONARY OF IBM & COMPUTING > TERMINOLOGY) > > mainframe n. A computer, usually in a computer center, with extensive > capabilities and > resources to which other computers may be connected so that they can share > facilities. > Originally referred to the central processing unit of a large computer, > which occupied the largest or central frame (rack). > > In case of IBM z, a single component doesn't doesn't make it a mainframe. > It's the whole system i.e. microprocessor, cache, memory, I/O Subsystem, > PR/SM, microcode/firmware, instruction set , RAS, Security etc etc etc. > > I suggest, comparison of individual components of IBM z with individual > components of other technologies is not valid. > > > From: IBM Mainframe Discussion List on behalf > of Jon Perryman > Sent: 29 July 2023 17:28 > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Definition of mainframe? Was: Ars Technica > > Can anyone provide the definition of MAINFRAME? The ARS Technica article > is complete nonsense because the mainframe is a state of mind and nothing > to do with reality. Can anyone prove me wrong? > https://arstechnica.com/information-technology/2023/07/the-ibm-mainframe-how-it-runs-and-why-it-survives/ > . > > The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. > Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I > suspect it still uses a PCIe zCPU card. I can't say with any certainty, but > I suspect that z/OS will run on a PC by using Hercules. What is the > definition of MAINFRAME? > > 1. CPU does not make a mainframe: The smallest IBM z16 (39 user cores of > the 64 cores) is the same as an AMD Ryzen 4.2Ghz CPU (64 user cores of 64 > cores). The largest IBM z16 (200 user cores of the 256 cores) is the same > as 4 AMD Ryzen CPU on 1 motherboard (256 user cores of the 256 cores). Both > are CISC CPU (AMD uses X86 instructions versus IBM z instructions). IBM > Telum (5.2Ghz) has a slightly faster clock than AMD Ryzen (4.2Ghz) but is > offset by the 25% extra user cores. IBM z16 has 4 motherboards for 16 CPU > and the same AMD Ryzen would need 1 motherboard for 4 CPU. > > 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are > also on every modern motherboard. IBM z16 chooses not to include other > hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have > 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and > more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if > there was enough customer demand. > > 3. OS does not make a mainframe. Linux running on z16 doesn't make it > mainframe Linux. There's nothing stopping Linux from taking advantage of > every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to > build the Linux software. IBM hasn't duplicated z/OS software features in > Linux. > > 4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for > z/OS. DB2 for Linux runs on all hardware including z16. With Linux, you can > still run DB2 on z16 but large customers choose DB2 for z/OS. > > ASK YOURSELF: Other than design philosophy, name 1 fundamental difference > between IBM z16, AMD Ryzen and the software. > > ASK YOURSELF: Since design philosophy is the only difference, name the > philosophy that makes a mainframe. > > Despite the story's false claims for z/OS relevance, it is ignorance in > the Linux community that makes IBM z/OS relevant. Specifically, it's the > lack of design in Linux. Consider DB2 for Linux and DB2 for z/OS which are > the same product both from IBM and available on an IBM z16. Linux people > tell you they provide the same results, but they ignore the intrinsic > capabilities of z/OS design. DB2 for Linux supports high availability and > large databases but it requires knowledge of big data solutions, Linux > clustering solutions and more. Add a computer to the cluster and you must > replicate the master disk. Take a computer offline from the cluster, then > it must re-sync or replicate the
Re: Definition of mainframe? Was: Ars Technica
IBM's definition of mainframe (Source: DICTIONARY OF IBM & COMPUTING TERMINOLOGY) mainframe n. A computer, usually in a computer center, with extensive capabilities and resources to which other computers may be connected so that they can share facilities. Originally referred to the central processing unit of a large computer, which occupied the largest or central frame (rack). In case of IBM z, a single component doesn't doesn't make it a mainframe. It's the whole system i.e. microprocessor, cache, memory, I/O Subsystem, PR/SM, microcode/firmware, instruction set , RAS, Security etc etc etc. I suggest, comparison of individual components of IBM z with individual components of other technologies is not valid. From: IBM Mainframe Discussion List on behalf of Jon Perryman Sent: 29 July 2023 17:28 To: IBM-MAIN@LISTSERV.UA.EDU Subject: Definition of mainframe? Was: Ars Technica Can anyone provide the definition of MAINFRAME? The ARS Technica article is complete nonsense because the mainframe is a state of mind and nothing to do with reality. Can anyone prove me wrong? https://arstechnica.com/information-technology/2023/07/the-ibm-mainframe-how-it-runs-and-why-it-survives/. The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I suspect it still uses a PCIe zCPU card. I can't say with any certainty, but I suspect that z/OS will run on a PC by using Hercules. What is the definition of MAINFRAME? 1. CPU does not make a mainframe: The smallest IBM z16 (39 user cores of the 64 cores) is the same as an AMD Ryzen 4.2Ghz CPU (64 user cores of 64 cores). The largest IBM z16 (200 user cores of the 256 cores) is the same as 4 AMD Ryzen CPU on 1 motherboard (256 user cores of the 256 cores). Both are CISC CPU (AMD uses X86 instructions versus IBM z instructions). IBM Telum (5.2Ghz) has a slightly faster clock than AMD Ryzen (4.2Ghz) but is offset by the 25% extra user cores. IBM z16 has 4 motherboards for 16 CPU and the same AMD Ryzen would need 1 motherboard for 4 CPU. 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also on every modern motherboard. IBM z16 chooses not to include other hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was enough customer demand. 3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. IBM hasn't duplicated z/OS software features in Linux. 4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for z/OS. DB2 for Linux runs on all hardware including z16. With Linux, you can still run DB2 on z16 but large customers choose DB2 for z/OS. ASK YOURSELF: Other than design philosophy, name 1 fundamental difference between IBM z16, AMD Ryzen and the software. ASK YOURSELF: Since design philosophy is the only difference, name the philosophy that makes a mainframe. Despite the story's false claims for z/OS relevance, it is ignorance in the Linux community that makes IBM z/OS relevant. Specifically, it's the lack of design in Linux. Consider DB2 for Linux and DB2 for z/OS which are the same product both from IBM and available on an IBM z16. Linux people tell you they provide the same results, but they ignore the intrinsic capabilities of z/OS design. DB2 for Linux supports high availability and large databases but it requires knowledge of big data solutions, Linux clustering solutions and more. Add a computer to the cluster and you must replicate the master disk. Take a computer offline from the cluster, then it must re-sync or replicate the master disk. DB2 on z/OS does not experience these problems because of z/OS shared dasd and dasd mirroring. ASK YOURSELF: Name 1 brilliant feature design that originated directly from Linux or Unix. Please don't use features that originated from IBM (e.g. databases, SQL, HTML, Cloud and more). Brilliant feature design exposes very little. For instance, does anyone know the problems solved by z/OS shared dasd and dasd mirroring. Linux people on the other hand can easily name those problems solved if you mention clustering solutions and big data solutions. I've personally seen one sysplex split between 2 sites 40 KM apart using line of site satellite dishes for communication, yet z/OS app programmers were informed. In other words, IBM designs for the 21st century. ASK YOURSELF: Name 1 brilliant unnoticed Linux feature. Name several brilliant unnoticed z/OS features. The story claims Linux feature design is similar to z/OS feature design. For example, the story
Re: Definition of mainframe? Was: Ars Technica
COBOL MOVE was not intuitive. Should have been PROPOGATE or COPY, COPY was already taken I guess. On Mon, Jul 31, 2023 at 1:55 PM Grant Taylor < 023065957af1-dmarc-requ...@listserv.ua.edu> wrote: > On 7/30/23 7:58 PM, Andrew Rowley wrote: > > They do dynamicaly expand. It's not growing that's the problem though, > > it's shrinking - releasing space so that it can be used by another user. > > I feel like shrinking is a thing for many file systems. The utility to > shrink may not be included with the OS and need to be installed or even > come from a 3rd party. > > Not all file systems can be expanded much less shrunk while mounted. > Many of the ones that I've worked with need to be unmounted to do such > actions. > > Usually, such actions also require the support of some sort of resizable > container to put the file system in. This is often Logical Volume > Manager on Linux (across platforms). > > > > Grant. . . . > > -- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- Wayne V. Bickerdike -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/30/23 7:58 PM, Andrew Rowley wrote: They do dynamicaly expand. It's not growing that's the problem though, it's shrinking - releasing space so that it can be used by another user. I feel like shrinking is a thing for many file systems. The utility to shrink may not be included with the OS and need to be installed or even come from a 3rd party. Not all file systems can be expanded much less shrunk while mounted. Many of the ones that I've worked with need to be unmounted to do such actions. Usually, such actions also require the support of some sort of resizable container to put the file system in. This is often Logical Volume Manager on Linux (across platforms). Grant. . . . -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Mainframe - the greatest computer hardware ever developed & continues to be developed. Sent from Yahoo Mail for iPhone On Sunday, July 30, 2023, 7:36 PM, Paul Gilmartin <042bfe9c879d-dmarc-requ...@listserv.ua.edu> wrote: On Mon, 31 Jul 2023 08:50:39 +1000, Andrew Rowley wrote: > >An automounted filesystem per user has always been a terrible idea. I >think it was given as an example of how you could use automount and >somehow morphed into a recommendation. (Other OSes can e.g. use >automount to mount a remote user filesystem via NFS). > >Reasons it's a bad idea: > >1) Freespace in the filesystem is not shared between users. This means >that you need much more space than if there was one pool of freespace >shared between all. > It mimics the MVS tradition of overallocating datasets. Aren't modern filesystems virtual and dynamically extensible? >2) It makes simple questions like e.g. "Which users have a >.ssh/authorized_keys file?" much harder to answer. > Hmmm... Use RACF to enumerate hone directories in OMVS segments. The "hard" then is just the performance cost of so many automounts. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 31/07/2023 9:36 am, Paul Gilmartin wrote: It mimics the MVS tradition of overallocating datasets. Aren't modern filesystems virtual and dynamically extensible? They do dynamicaly expand. It's not growing that's the problem though, it's shrinking - releasing space so that it can be used by another user. Hmmm... Use RACF to enumerate hone directories in OMVS segments. The "hard" then is just the performance cost of so many automounts. One of the claimed advantages of automount was that user filesystems could be migrated by HSM. Enumerating the users is fine if the filesystems are all instantly available. If you have a few thousand that need to be recalled from HSM... Does HSM release unused space from the filesystem when it is migrated and recalled, or do you need enough DASD to allocate all the empty space in all the filesystems? -- Andrew Rowley Black Hill Software -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Mon, 31 Jul 2023 08:50:39 +1000, Andrew Rowley wrote: > >An automounted filesystem per user has always been a terrible idea. I >think it was given as an example of how you could use automount and >somehow morphed into a recommendation. (Other OSes can e.g. use >automount to mount a remote user filesystem via NFS). > >Reasons it's a bad idea: > >1) Freespace in the filesystem is not shared between users. This means >that you need much more space than if there was one pool of freespace >shared between all. > It mimics the MVS tradition of overallocating datasets. Aren't modern filesystems virtual and dynamically extensible? >2) It makes simple questions like e.g. "Which users have a >.ssh/authorized_keys file?" much harder to answer. > Hmmm... Use RACF to enumerate hone directories in OMVS segments. The "hard" then is just the performance cost of so many automounts. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 30/07/2023 2:28 am, Jon Perryman wrote: ASK YOURSELF: Name the z/OS Unix feature that sort of fixes the fundamental design flaw with Unix filesystems just described? I suspect most people won't think about each user having a unique filesystem using automount to make their filesystem available. Typical Unix uses one file system with all users having directories in the /user directory. An automounted filesystem per user has always been a terrible idea. I think it was given as an example of how you could use automount and somehow morphed into a recommendation. (Other OSes can e.g. use automount to mount a remote user filesystem via NFS). Reasons it's a bad idea: 1) Freespace in the filesystem is not shared between users. This means that you need much more space than if there was one pool of freespace shared between all. 2) It makes simple questions like e.g. "Which users have a .ssh/authorized_keys file?" much harder to answer. A filesystem per user is basically equivalent to a SMS storage group and catalog per user. You get isolation between users, but at the expense of much more difficult management. -- Andrew Rowley Black Hill Software -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
> On Saturday, July 29, 2023 at 02:36:12 PM PDT, Rick Troth > wrote: > Your inquiry is (understandably) somewhat of a reaction against > unfortunate trends in public thinking. IBM doesn't have a definition. I can't define mainframe because the only distinction I could find is design philosophy. Surely people in this group can define mainframe. Like z16, all modern computers have a CPU, RAM and PCIe slots. What criteria do people in this group use to identify a mainframe? > Your #2 is a miss. Hardware *does* make a mainframe: channelized I/O Like IBM, other manufacturers now build multi-disk PCIe cards which provide some form of channel support. Installing these cards does not make them a mainframe. Channel support may not be on the level of IBM but it's still channels. IBM has chosen PCIe for all expansion whereas other manufactures chose additional support thru SATA, IDE and various other techniques. Granted that IBM makes far better implementation choices but are we saying that mainframe comes down to simple choices? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Sun, 30 Jul 2023 17:32:54 -0400, Bob Bridges wrote: > >... But it never seemed to me that COBOL statements were any easier to > learn, or more intuitive, than those of FORTRAN or Basic. > In defense of verbosity: Once in the late 1960s I counseled a physics graduate student who was struggling to learn FORTRAN. He coded many assignment statements that corresponded to elements of a matrix, then PRINT He came to me asking why the computer had not found the solution to a system of linear equations. since then, perhaps earlier, I have disliked the use of "=" for assignment. Some languages do better with "SET variable = expression", or Pascal with "variable := expression" (the asymmetric delimiter is informative.) C tries and perhaps does worse by using "=" for assignment but something else for a relational operator. Rexx and PL/I do yet worse by using "=" for both and depending on context-sensitivity. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
I assumed that too (and laughed aloud at the time). The man who introduced me to computer programming (blessings upon him!) got us writing code the very first day. I remember him asking us "so you have to write a program that compares two numbers and tells you which one is greater. What's the first thing the program has to do?" After a few wrong guesses from us (write out the bigger number? Look at the two numbers?) he said "You have to GET THE FIRST NUMBER", and he wrote GET NUMBERA on the board. I suppose he spent a (very) little time explaining about a variable name before getting us to tell him that the second statement should be GET NUMBERB. The class was in PL/1, so GET and PUT were right there waiting for him to use without having to explain very much. I don't know whether it was because of this approach, or because I'm just naturally drawn to such things (and there's no doubt I am), or maybe I've simply forgotten after all these years what it was like to learn a computer language for the first time. But most computer languages seem pretty obvious to me. Oh, I wasted some time being confused about the concept of methods in VBA, when I first started using it, and of course APL is an exception. So, maybe, is LISP, though I never seriously tackled it. But it never seemed to me that COBOL statements were any easier to learn, or more intuitive, than those of FORTRAN or Basic. And the structure! All that stuff about the four divisions, and especially the ENVIRONMENT division, I didn't find them intuitive at all. But I'm not so much saying that you're wrong about COBOL being easy to learn as that personally I find ALL languages easy to learn - and that may be just an idiosyncrasy of mine, especially having learned a number of them. And by the way, we were six weeks into that PL/C class when I ran across someone taking COBOL the same semester. They were just learning about the concept of loops, and had not yet written their first program. That's a terrible way to learn coding, for which I blame not COBOL but their instructor. If for my sins I ever have to teach a COBOL class, I may not be able to get them writing PROCEDURE DIVISION statements the first day, but surely by the second... --- Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313 /* It is always the right time to do the right thing. -Martin Luther King, Jr. */ -Original Message- From: IBM Mainframe Discussion List On Behalf Of Jon Perryman Sent: Sunday, July 30, 2023 16:57 I assume this is sarcasm about problems with Cobol. There are very few peculiarities to Cobol and these are often easily learned very quickly. Languages like C and C++ are not intuitive to a non-computer person. Of the languages, which is more intuitive to a layperson? --- On Saturday, July 29, 2023 at 01:50:52 PM PDT, Paul Gilmartin <042bfe9c879d-dmarc-requ...@listserv.ua.edu> wrote: > However, COBOL can be coded using everyday, non-specialized English > vocabulary such as "LEVEL 77". -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Saturday, July 29, 2023 at 01:50:52 PM PDT, Paul Gilmartin <042bfe9c879d-dmarc-requ...@listserv.ua.edu> wrote: > However, COBOL can be coded using everyday, > non-specialized English vocabulary such as "LEVEL 77". I assume this is sarcasm about problems with Cobol. There are very few peculiarities to Cobol and these are often easily learned very quickly. Languages like C and C++ are not intuitive to a non-computer person. Of the languages, which is more intuitive to a layperson? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
> On Saturday, July 29, 2023 at 12:22:22 PM PDT, Bob Bridges
> wrote:
> I reluctantly admit that COBOL has important strengths
> ("reluctant" only because I have a deep dislike of verbosity in coding),
> But there are tasks for which I like PL/1, or VBA, or REXX (or ooRexx), and
> so on.
Business is not about the languages we like or dislike. Cobol's biggest benefit
for the business is that there is very little to learn. Ever notice that
learning the language is far more interesting than learning about the business
problems? Does anyone doubt they couldn't easily rewrite Twitter in Cobol on
z/OS? Twitter isn't more complicated than banking software. Cobol forces you to
focus on the business instead of computers. PL/1, VBA, REXX, JavaScript, HTML
are far more interesting than the needs of the business.
--
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Re: Definition of mainframe? Was: Ars Technica
On 7/30/23 12:42, Paul Gilmartin wrote: On Sun, 30 Jul 2023 10:56:08 -0500, Dave Jones wrote: Pretty sure it was CMS. Do you know the chronology? When was the CMS(?) based HTTPD created? Was SFS available at that date? MDFS is a poor fit for HTTP paths. There were several web servers available for VM early on. One I was fond of was based on Pipelines and did hierarchical content even on flat CMS minidisks. If you had SFS, you could go that route and have a storage-based hierarchy. The server figgered it out. Flexible. -- R; <>< -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Got it, thanks. So the 1600 slots is related to the 1536 ports you previously mentioned. The problem with that calculation is that you can't just take the 4 CPC's x 12 fanout slots = 48 I/O drawers. There's nowhere near enough room for that many drawers - you'd have to stack about 9 on top of each frame :) It's not very clear in that Redbook, but see the chart on the bottom of page 19, "Frames and cabling". z16 limit = 12 I/O drawers. On 7/30/2023 9:25 AM, Jon Perryman wrote: > On Saturday, July 29, 2023 at 12:18:04 PM PDT, Tom Brennan wrote: Where does "1,600 PCIe slots" come from? If I calculated max configurable PCIe slots correctly, 4 CPC drawers * 12 PCIe+ fanout adapters * 2 fanout ports per adapter * 16 PCIe+ slots in each drawer = 1,536 PCIe+ slots. Sorry that I couldn't remember the exact number but I also said PCIe instead of PCIe+. PCIe by other manufactures comes in 8, 16 & 32 wires (called lanes where each lane transmits 1 bit). I suspect that PCIe+ is 64 lanes transmitting 64 bits simultaneously. These are beasts compared to PC PCIe slots but the implementation is the same. On page 22 of https://www.redbooks.ibm.com/redbooks/pdfs/sg248950.pdf Fanouts - Each CPC drawer supports up to 12 PCIe+ fanout adapters to connect to the PCIe+ I/O drawers, and Integrated Coupling Adapter Short Reach (ICA SR) coupling links: – A 2-port Peripheral Component Interconnect Express (PCIe) 16 GBps I/O fanout. Each port supports one domain in the 16-slot PCIe+ I/O drawers . – ICA SR1.1 and ICA SR PCIe fanouts for coupling links (two links of 8 GBps each). On Saturday, July 29, 2023 at 12:18:04 PM PDT, Tom Brennan wrote: Where does "1,600 PCIe slots" come from? On 7/29/2023 9:28 AM, Jon Perryman wrote: 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also on every modern motherboard. IBM z16 chooses not to include other hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was enough customer demand. 3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. IBM hasn't duplicated z/OS software features in Linux. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Sun, 30 Jul 2023 12:11:11 -0400, Rick Trot wrote: >On 7/30/23 11:49, Paul Gilmartin wrote: >> On Sun, 30 Jul 2023 10:38:59 -0500, Dave Jones wrote: >>> 3) The original web browse was written of a Next, but the web server that >>> served out the pages ran on IBM's VM/ESA. >>> >> What guest OS? > >CMS, which technically is a "guest OS". > > Why the "technically" qualification? Aren't all guest OSes technically guest OSes? Is the distinction whether it IPLs from a saved segment or a disk image? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Sun, 30 Jul 2023 10:56:08 -0500, Dave Jones wrote: >Pretty sure it was CMS. > Do you know the chronology? When was the CMS(?) based HTTPD created? Was SFS available at that date? MDFS is a poor fit for HTTP paths. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
> On Saturday, July 29, 2023 at 12:18:04 PM PDT, Tom Brennan > wrote: > Where does "1,600 PCIe slots" come from? If I calculated max configurable PCIe slots correctly, 4 CPC drawers * 12 PCIe+ fanout adapters * 2 fanout ports per adapter * 16 PCIe+ slots in each drawer = 1,536 PCIe+ slots. Sorry that I couldn't remember the exact number but I also said PCIe instead of PCIe+. PCIe by other manufactures comes in 8, 16 & 32 wires (called lanes where each lane transmits 1 bit). I suspect that PCIe+ is 64 lanes transmitting 64 bits simultaneously. These are beasts compared to PC PCIe slots but the implementation is the same. On page 22 of https://www.redbooks.ibm.com/redbooks/pdfs/sg248950.pdf Fanouts - Each CPC drawer supports up to 12 PCIe+ fanout adapters to connect to the PCIe+ I/O drawers, and Integrated Coupling Adapter Short Reach (ICA SR) coupling links: – A 2-port Peripheral Component Interconnect Express (PCIe) 16 GBps I/O fanout. Each port supports one domain in the 16-slot PCIe+ I/O drawers . – ICA SR1.1 and ICA SR PCIe fanouts for coupling links (two links of 8 GBps each). On Saturday, July 29, 2023 at 12:18:04 PM PDT, Tom Brennan wrote: Where does "1,600 PCIe slots" come from? On 7/29/2023 9:28 AM, Jon Perryman wrote: > 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are > also on every modern motherboard. IBM z16 chooses not to include other > hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have > 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and > more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if > there was enough customer demand. > > 3. OS does not make a mainframe. Linux running on z16 doesn't make it > mainframe Linux. There's nothing stopping Linux from taking advantage of > every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to > build the Linux software. IBM hasn't duplicated z/OS software features in > Linux. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/30/23 11:49, Paul Gilmartin wrote: On Sun, 30 Jul 2023 10:38:59 -0500, Dave Jones wrote: 3) The original web browse was written of a Next, but the web server that served out the pages ran on IBM's VM/ESA. What guest OS? CMS, which technically is a "guest OS". -- R; <>< -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Pretty sure it was CMS. DJ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On Sun, 30 Jul 2023 10:38:59 -0500, Dave Jones wrote: > >3) The original web browse was written of a Next, but the web server that >served out the pages ran on IBM's VM/ESA. > What guest OS? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
While I agree with most of the points made by the original poster, a couple of nits: 1) zPDT is a software-only toolno special chips or PC boards involved. 2) HTML was inspired by - or evolved from - IBM's GML 3) The original web browse was written of a Next, but the web server that served out the pages ran on IBM's VM/ESA. Good discussions, though. +1 DJ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
On 7/29/23 11:28 AM, Jon Perryman wrote: Can anyone provide the definition of MAINFRAME? The ARS Technica article is complete nonsense because the mainframe is a state of mind and nothing to do with reality. Can anyone prove me wrong? I tend to agree that mainframe can be a state of mine which is formed by history and available associated technical solutions. The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I suspect it still uses a PCIe zCPU card. I can't say with any certainty, but I suspect that z/OS will run on a PC by using Hercules. What is the definition of MAINFRAME? I'm fairly certain that zPDT and RDz are purely software emulated mainframes. I've not seen anything like the P/390-E card in a long time. I also know for a fact that people have gotten some versions of z/OS to run in Hercules. 1. CPU does not make a mainframe: I think that the CPU and what it's optimized to do hints at what it is well suited to be used for. I've seen video evidence of a single human being tugging an air plane from the gate. But that doesn't mean that airports are giving up on their tug vehicles. 2. Hardware does not make a mainframe. I think that the hardware and what it's optimized to do hints at what it is well suited to be used for. 3. OS does not make a mainframe. I think that an OS and what it's optimized to do hints at it is well suited to be used for. I know that my last three comments have effectively been an "it is what it is" type of answer. But the crux of it is that the $THING has been optimized to do the task that it's employed to do. I wouldn't use an El Camino to haul rolls of steal to a factory any more than I would use an eighteen wheeler to deliver a pizza. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. I question the veracity of that statement. Let's start with this - please share one z16 feature that Linux doesn't use so that we can discuss it. I'm sure there are a number of them. But I suspect the reason that Linux doesn't use it is for possibly surprising reasons. Reasons that are probably rooted in the origins of things. IBM hasn't duplicated z/OS software features in Linux. I actually largely agree with that statement. To me, the biggest things that differentiates the mainframe / z/OS / etc. from Linux is the other facilities that the mainframe / z/OS provide. I think the package suite / solution stack that is the mainframe to be the most salient thing that differentiates the mainframe from non-mainframes. I've read many articles / heard (recordings of / videos of) some discussions where people say that porting applications from z/OS to Linux isn't a matter of re-compiling things. Sure, the code will, or can be made to, compile on Linux. But many the supporting facilities that z/OS provides are completely non-existent. 4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for z/OS. I think that significant differentiators actually are software. It's just not -- what I'm going to call -- the primary line of business software like DB2 / Domino / SAP / etc. I think it's other software, CICS, RACF, IMS, etc. that provide supporting services afor the primary line of business applications. DB2 for Linux runs on all hardware including z16. With Linux, you can still run DB2 on z16 but large customers choose DB2 for z/OS. I take what others are doing with a huge grain of salt. I've seen too many businesses continue to run something somewhere that it has been running for a long time because of non-technical reasons. People. Support. Technical debt. ASK YOURSELF: Since design philosophy is the only difference, name the philosophy that makes a mainframe. From what I've seen, the mainframe has integrated reliability, availability, and serviceability (RAS) at the hardware and OS level. Conversely, Open Systems tend to not have the RAS capabilities that the mainframe has. As such, Open Systems application designers have integrated RAS like features at different levels if they cared to have them because the hardware / OS didn't provide them. Despite the story's false claims for z/OS relevance, it is ignorance in the Linux community that makes IBM z/OS relevant. Specifically, it's the lack of design in Linux. Consider DB2 for Linux and DB2 for z/OS which are the same product both from IBM and available on an IBM z16. Linux people tell you they provide the same results, but they ignore the intrinsic capabilities of z/OS design. Does ignoring the intrinsic capabilities of z/OS design alter what the DB2 on z/OS vs DB2 on Linux on z is capable of doing? I'm talking brutal dollar for dollar, pound for pound, BTU
Re: Definition of mainframe? Was: Ars Technica
I do like PL/1 very much. PL/C (a subset) was the first language I ever learned, and although I have used lots of others since then I am still favorably impressed with PL/1's full control over storage. Unfortunately I haven't written anything in it in a couple decades, so maybe the golden haze hovering over my memories of it aren't the best indication of its value compared to other languages. And as a coder who spends most of his time writing customized commands and utilities rather than applications, I tend to prefer interpreters over compilers. --- Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313 /* People seem not to see that their opinion of the world is also a confession of their character. -Ralph Waldo Emerson */ -Original Message- From: IBM Mainframe Discussion List On Behalf Of Paul Gilmartin Sent: Saturday, July 29, 2023 16:51 I thought PL/1 is "The only programming language you'll ever need." However, COBOL can be coded using everyday, non-specialized English vocabulary such as "LEVEL 77". --- On Sat, 29 Jul 2023 15:22:10 -0400, Bob Bridges wrote: > Ok, so I'm a software geek, I admit it. But there are tasks for > which I like PL/1, or VBA, or REXX (or ooRexx), and so on. > >"Need"? Maybe not absolutely must have, but they're sure helpful. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Your inquiry is (understandably) somewhat of a reaction against unfortunate trends in public thinking. I will respond to them separately. First is triggered by the subject line: definition of a mainframe. Your #2 is a miss. Hardware *does* make a mainframe: channelized I/O Let me explain. Remember the VAX? DEC wanted to market their box as a "mainframe". In those days, I was quite fond of the VAX, and of its most common O/S, VMS. (Later, I went back to VMS and ... oy vey ... trying to forget it.) So foreign to me after being away. But VAX hardware was redeemed (I say, not meaning to slam VMS) by Unix and Linux being ported to it. SATA is great, but doesn't count. It doesn't scale to the same extent. FCP counts, but few machines talking FCP go to the same scaling as IBM Z "clients". So not all machines doing SATA or FCP or SCSI qualify as mainframes if only because they don't go all-in with such I/O models. Why was the VAX not a mainframe, as DEC wanted customers to believe? It lacked channelized I/O. Not that it didn't have good input/output facilities, but that it didn't have the same concepts, systems, services, and sub-processors as machines from IBM (and others). IBM is not the only company to produce large systems with channelized I/O. Some vendors, in fact, used plug-compatible devices. Sweet! (Though they might have called their machines "supercomputers". Okay, fine. And some IBM mainframes were called "supercomputers" at one time. But that's a whole nutha story.) So the single significant feature of "a mainframe" in my glossary is channelized I/O. -- R; <>< On 7/29/23 12:28, Jon Perryman wrote: Can anyone provide the definition of MAINFRAME? The ARS Technica article is complete nonsense because the mainframe is a state of mind and nothing to do with reality. Can anyone prove me wrong? https://arstechnica.com/information-technology/2023/07/the-ibm-mainframe-how-it-runs-and-why-it-survives/. The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I suspect it still uses a PCIe zCPU card. I can't say with any certainty, but I suspect that z/OS will run on a PC by using Hercules. What is the definition of MAINFRAME? 1. CPU does not make a mainframe: The smallest IBM z16 (39 user cores of the 64 cores) is the same as an AMD Ryzen 4.2Ghz CPU (64 user cores of 64 cores). The largest IBM z16 (200 user cores of the 256 cores) is the same as 4 AMD Ryzen CPU on 1 motherboard (256 user cores of the 256 cores). Both are CISC CPU (AMD uses X86 instructions versus IBM z instructions). IBM Telum (5.2Ghz) has a slightly faster clock than AMD Ryzen (4.2Ghz) but is offset by the 25% extra user cores. IBM z16 has 4 motherboards for 16 CPU and the same AMD Ryzen would need 1 motherboard for 4 CPU. 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also on every modern motherboard. IBM z16 chooses not to include other hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was enough customer demand. 3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. IBM hasn't duplicated z/OS software features in Linux. 4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for z/OS. DB2 for Linux runs on all hardware including z16. With Linux, you can still run DB2 on z16 but large customers choose DB2 for z/OS. ASK YOURSELF: Other than design philosophy, name 1 fundamental difference between IBM z16, AMD Ryzen and the software. ASK YOURSELF: Since design philosophy is the only difference, name the philosophy that makes a mainframe. Despite the story's false claims for z/OS relevance, it is ignorance in the Linux community that makes IBM z/OS relevant. Specifically, it's the lack of design in Linux. Consider DB2 for Linux and DB2 for z/OS which are the same product both from IBM and available on an IBM z16. Linux people tell you they provide the same results, but they ignore the intrinsic capabilities of z/OS design. DB2 for Linux supports high availability and large databases but it requires knowledge of big data solutions, Linux clustering solutions and more. Add a computer to the cluster and you must replicate the master disk. Take a computer offline from the cluster, then it must re-sync or replicate the master disk. DB2 on z/OS does not experience these problems because of z/OS shared dasd and dasd mirroring. ASK YOURSELF: Name 1 brilliant feature design that originated directly from Linux or Unix. Please don't use features that originated from IBM (e.g.
Re: Definition of mainframe? Was: Ars Technica
On Sat, 29 Jul 2023 15:22:10 -0400, Bob Bridges wrote: > Ok, so I'm a software geek, I admit it. But there are tasks for > which I like PL/1, or VBA, or REXX (or ooRexx), and so on. > >"Need"? Maybe not absolutely must have, but they're sure helpful. > I thought PL/1 is "The only programming language you'll ever need." However, COBOL can be coded using everyday, non-specialized English vocabulary such as "LEVEL 77". >-Original Message- >From: Jon Perryman >Sent: Saturday, July 29, 2023 12:28 > >The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. >Linux will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I >suspect it still uses a PCIe zCPU card. I can't say with any certainty, but I >suspect that z/OS will run on a PC by using Hercules. What is the definition >of MAINFRAME? > How does performance of MVS 3.8 on Hercules compare with the original hardware? ... >ASK YOURSELF: Name 1 fundamental difference between a PDS/e and a Unix >filesystem. > Cross-directory links and symbolic links Remember that CKD DASD, VSAM, and PDSE are all emulated nowadays on FBA disks. ... >The story falsely claims Cobol is an ancient language. Big data, clustering >and more are hidden by z/OS. VSAM is simple and efficient to use in Cobol but >Linux programmers must use databases for the same purpose. What;s wrong with a database? Isn't VSAM just a z-peculiar instance of a database. There should be an "advocacy" sub-list. Whom are you trying to convert? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Definition of mainframe? Was: Ars Technica
Many interesting points here, and even if I were interested in contradicting
them I'm too ignorant of hardware to attempt it. But I will at least say that
I'm very, very glad to have multiple algorithmic languages to write in, not
just COBOL. I reluctantly admit that COBOL has important strengths
("reluctant" only because I have a deep dislike of verbosity in coding), but
before I learned COBOL I already was using at least four other languages and
after I (mostly) stopped using it I tacked on some more. Ok, so I'm a software
geek, I admit it. But there are tasks for which I like PL/1, or VBA, or REXX
(or ooRexx), and so on.
"Need"? Maybe not absolutely must have, but they're sure helpful.
Again, not saying I disagree.
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* Somehow or other an extraordinary idea has arisen that the disbelievers in
miracles consider them coldly and fairly, while believers in miracles accept
them only in connection with some dogma. The fact is quite the other way. The
believers in miracles accept them (rightly or wrongly) because they have
evidence for them. The disbelievers in miracles deny them (rightly or wrongly)
because they have a doctrine against them. -G.K. Chesterton, _Orthodoxy_ */
-Original Message-
From: IBM Mainframe Discussion List On Behalf Of Jon
Perryman
Sent: Saturday, July 29, 2023 12:28
Can anyone provide the definition of MAINFRAME? The ARS Technica article is
complete nonsense because the mainframe is a state of mind and nothing to do
with reality. Can anyone prove me wrong?
https://arstechnica.com/information-technology/2023/07/the-ibm-mainframe-how-it-runs-and-why-it-survives/.
The IBM z16 is just 4 motherboards containing 16 CPU and many PCIe slots. Linux
will run on an IBM z16. Is a PC also mainframe? Forget zPDT because I suspect
it still uses a PCIe zCPU card. I can't say with any certainty, but I suspect
that z/OS will run on a PC by using Hercules. What is the definition of
MAINFRAME?
1. CPU does not make a mainframe: The smallest IBM z16 (39 user cores of the 64
cores) is the same as an AMD Ryzen 4.2Ghz CPU (64 user cores of 64 cores). The
largest IBM z16 (200 user cores of the 256 cores) is the same as 4 AMD Ryzen
CPU on 1 motherboard (256 user cores of the 256 cores). Both are CISC CPU (AMD
uses X86 instructions versus IBM z instructions). IBM Telum (5.2Ghz) has a
slightly faster clock than AMD Ryzen (4.2Ghz) but is offset by the 25% extra
user cores. IBM z16 has 4 motherboards for 16 CPU and the same AMD Ryzen would
need 1 motherboard for 4 CPU.
2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also
on every modern motherboard. IBM z16 chooses not to include other hardware
(e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe
slots. IBM could allow PCIe graphics cards, mice, keyboards and more.
Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was
enough customer demand.
3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe
Linux. There's nothing stopping Linux from taking advantage of every z16
hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the
Linux software. IBM hasn't duplicated z/OS software features in Linux.
4. Software does not make a mainframe. IBM sells DB2 for Linux and DB2 for
z/OS. DB2 for Linux runs on all hardware including z16. With Linux, you can
still run DB2 on z16 but large customers choose DB2 for z/OS.
ASK YOURSELF: Other than design philosophy, name 1 fundamental difference
between IBM z16, AMD Ryzen and the software.
ASK YOURSELF: Since design philosophy is the only difference, name the
philosophy that makes a mainframe.
Despite the story's false claims for z/OS relevance, it is ignorance in the
Linux community that makes IBM z/OS relevant. Specifically, it's the lack of
design in Linux. Consider DB2 for Linux and DB2 for z/OS which are the same
product both from IBM and available on an IBM z16. Linux people tell you they
provide the same results, but they ignore the intrinsic capabilities of z/OS
design. DB2 for Linux supports high availability and large databases but it
requires knowledge of big data solutions, Linux clustering solutions and more.
Add a computer to the cluster and you must replicate the master disk. Take a
computer offline from the cluster, then it must re-sync or replicate the master
disk. DB2 on z/OS does not experience these problems because of z/OS shared
dasd and dasd mirroring.
ASK YOURSELF: Name 1 brilliant feature design that originated directly from
Linux or Unix. Please don't use features that originated from IBM (e.g.
databases, SQL, HTML, Cloud and more).
Brilliant feature design exposes very little. For instance, does anyone know
the problems solved by z/OS shared dasd and dasd mirroring. Linux people on the
other hand can easily name those problems solved if you
Re: Definition of mainframe? Was: Ars Technica
Where does "1,600 PCIe slots" come from? On 7/29/2023 9:28 AM, Jon Perryman wrote: 2. Hardware does not make a mainframe. IBM z16 has PCIe and ram which are also on every modern motherboard. IBM z16 chooses not to include other hardware (e.g. SATA, IDE, WIFI and more). Motherboards choose not to have 1,600 PCIe slots. IBM could allow PCIe graphics cards, mice, keyboards and more. Essentially, IBM z16 and AMD Ryzen can implement the same hardware if there was enough customer demand. 3. OS does not make a mainframe. Linux running on z16 doesn't make it mainframe Linux. There's nothing stopping Linux from taking advantage of every z16 hardware feature (e.g. 1,600 PCIe slots) but no one is willing to build the Linux software. IBM hasn't duplicated z/OS software features in Linux. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
