HI, Control cpu utlization in MFNetDisk.
if you run with the default MPCOPT configuration, then your TASKS number equal to 8. If you happy with your CPU utilization then you can continue to run with this parameter. If you run with high CPU utilization you can control it by changing the TASKS parameter number. In my test I run 6 jobs which run loop of IO. The CPU utilization was high. Just try to imagine that simultaneity six tasks emulate disk or tape emulation which include moving data with large size depand on the block size and much more CPU (Almost NO IO in MF MFNetDisk!). The only kind of IO is done to TCP. MFNetDisk can send IO request to task in wait, or can queue that IO request to IO requests queue. In case of decrease the number of task to 2, you will have only 2 tasks which working simultaneity and hard instead of 6 and 4 waiting to run when task will be available. In my test environment, the CPU utilization decrease by 50%. The total IO was almost the same. So check if TASKS=2 is good parameter for you only if you have problem with your MF CPU utilization. Be aware that you must test your CPU utilization when you have high load IO to MFNetDisk disks or tapes. To the people who download the beta PRO, please start to send information and feedback about what you see. In MF, IO can have many type of CCWs. Some CCWs are currently not handle in the best way. Example, PDS (not PDSE) compression with IEBCOPY require more development from my size to handle it better. Why? Because each IO contained smal number of CCWs (about 7) and only one read CCW, and more problem to the stacked CCWs is the PCI bit in the READ operation. Another problem in compression or using IEBCOPY for read PDS is that it use SEARCHID (x31) CCW to locate the BLOCKID. Search id and the read key and data with PCI bit set on which cause me to stop the stacking for this specific CCW. Of course in this case using the stacked CCW does not have any advance on the IO. Anyway some CCW in IEBCOPY are stacked, CCW SEEK(x07), DEFINEEXTENT (x63) and SETSECTOR(x23) and read MTCNT (x92) which are the first CCWs in typical IEBCOPY read IO are stacked. So from the TCP point of view, instead of having at least 7 TCP READ and WRITE ( SEEK,DX,SETSECTOR,READCNT,SRCHID,READKD,RDSECTOR) you will have 1 TCP for (SEEK,DX,SETSECTOR,RDMTCNT) instead of 4, then at least 1 TCP for SEARCHID and one TCP READKD with the PCI bit on. The last CCW (RDSECTOR) required another TCP. So, instead of 7 TCP in the old MFNetDisk, you will have 4. That is good but not enough for me. I have some idea how to improve the PDS stacked CCWs for IEBCOPY even better. Thanks, Shai On Mon, Jun 13, 2011 at 8:39 PM, shai hess <[email protected]> wrote: > HI, > > OK, I decide that everyone can try MFNetDisk PRO beta from now. > Again, this is beta. If you use it you are taking the risk that many bugs > may be in the new code. > I run some tests and it look OK to me but I know that most of the bugs you > will find for me. > The new code support the replication and the emulation tape and disk. > The replication in PRO is the same as the standard MFNetDisk. > Now some technical issue: > > The PCSERVER in the download file can run with stacked CCWs the PRO > version (version 13) and with the standard MFNetDIsk (version 12). > You can not run the MVS MFNetDisk PRO with the PCSERVER of the standard > MFNetDisk. The reason is that the data send from MF to PC has been changed. > > The MVS MFNetDisk PRO can not run with the OLD PCSERVER in PC. If you > doing so, pray for your disks and tapes data!!! > The old MVS MFNetDisk can run with the new PCSERVER. So, first shutdown > the old PCSERVER before continue to work!! > > So, do the following: > > 1. Do not use your production MFNetDisk disks and tapes with the PRO. > The PRO can run with your old MFNetDisk old disks and tapes but this > is beta product and bug can harm your data. > 2. Start the PRO PCServer in other PC and allocate new disks and tapes and > replication if you need. > You can not run the old PCSERVER and the PRO PCServer in the same PC > host together. > You can shutdown your old PCSERVER and start the new PCSERVER in your > PC. But as I said before, new bugs can harm your data. > 3. Start the new MVS PRO MFNetDIsk in your MVS system. If you need, > shutdown your old MFNetDisk MVS job. > 4. Start to work with the beta product. > 5. Let me know if you find bugs as soon as possible. > 6 This is beta code so, you do not need to run CODE_REQUEST for now. You > can find the beta PRO in the DOWNLOAD page under the YOUTUBE movies of > MFNetDIsk. > > Please let me know the results. More steps needed to be done to this > version to make bigger improvement but this code is doing good job in the > performance. > Please give me feedback about your finding using this version. > > Shai > > > ---------------------------------------------------------------------- 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
