Interesting patent related to SPKA http://www.google.com/patents/EP0558945A2?cl=en
Rob Schramm Senior Systems Consultant Imperium Group On Thu, Nov 15, 2012 at 4:17 PM, Schwartz, Alan <[email protected]>wrote: > There's a conflict here. The CA APAR says " This APAR will have a > greater affect on regions running STGPROT=NO." > Jim said " Therefore, on workloads (i.e. CICS running with > STGPROT=YES).... , this can show up as the z196 spending more time" > > Can't be both. > > Alan Schwartz > ITO Global Services Operations and Engineering > Xerox Business Services, LLC > 1500 Towerview Rd. > Eagan, MN. 55121-1346 > > p. 612.266.3150 > m. 651.274.5819 > f. 612.266.3196 > > > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of Jim Mulder > Sent: Thursday, November 15, 2012 12:57 PM > To: [email protected] > Subject: Re: CA Common services ENF Monitor reporting high CPU time > > > We observed, while using STROBE, apparent high CPU use in module > CAS9C66. > > From CA we found that they had the following on file:: > > > > APAR #: RO43562 > > Product: ENFCIC Release: 14.0 Solution #: 7 Type: > > OS: OS Group: GCCOMC ISL SUP 2 > > Title: PERFORMANCE ENHANCEMENT ON Z/196 PROCESSORS. > > > > ****************** VERSION 0 EFFECTIVE: MAR 31 2012 2:09 > > ****************** > > > > ***NOTE*** PE: YES CORRECTED BY: RO45646 > > > > PROBLEM DESCRIPTION: > > After a processor upgrade to z/196, some performance monitors may show > > increase cpu usage in various csects in the CAS9Cxx module. > > The flagged area is usually in a very tight range and will contain a > > SPKA instruction. This APAR will have a greater affect on regions > > running STGPROT=NO. > > > > SYMPTOMS: > > Performance monitors show increased activity in CAS9Cxx modules. > > > > We had just moved to a z196 and STROBE was being used to compare > > performance against the previous processor (no longer available for > > direct comparison). > > > > Since the z196 and z114 are from the same design cycle and zEC12 is > > similar to a z196 we have asked whether this situation could exist on > > a z114 or a zEC12 and they said no. > > > > Has anyone any idea why this might occur, and anyone has seen it on a > > z114 or zEC12. > > Is the set up code for a SPKA instruction something that would be very > > different on a z196 from any other processor? > > One of the CPU designers gave me the following explanation: > > System z processor development has identified an aspect of the z196 > processor that performs worse than the equivalent instruction on a z10 > processor. When an SPKA instruction is executed in problem state, the new > out-of-order design of the > z196 processor requires more pipeline stalls to give functionally correct > results than in prior generations of processors. > > Therefore, on workloads (i.e. CICS running with STGPROT=YES) that have an > intense amount of SPKAs in problem state, this can show up as the z196 > spending more time executing the SPKA instruction. Some vendor performance > tools or single instruction benchmarks may uncover this additional time > spent on the SPKA instruction. This change in SPKA behavior does not offset > the benefits the z196 provides for the CICS environment. > This aspect of the longer SPKA execution time can be exacerbated by > running on a subcapacity machine. > > > Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send email > to [email protected] with the message: INFO IBM-MAIN > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
