(ZOS) Performance diagnosis information

The following report options are listed here for information. IBM Service may request that we run one or more of these reports while assisting you with diagnosis. We do not need to collect this data unless it is requested by IBM Service.

• If we suspect that we are having throughput problems in a particular address space, for example by looking at some other real-time performance data, IBM Service may need to see a dump of one or more address spaces. This is done using the following parameters:

  
   JOBNAME=(<jobname list>)
   SDATA=(LSQA,PSA,SQA,SUM,SWA,TRT,WLM,CSA,RGN)
  
  

• If we suspect that the problem could be resulting from GRS latch or ENQ contention, check the RMF™ Enqueue Activity Report and enter the console command:

  
  D GRS,CONTENTION
  
  

  during a time period in which the performance problem is observed. SYS.BPX.A000.FSLIT.FILESYS.LSN represents HFS latches. Latch sets with a numeric suffix are file latches, specifically SYS.BPX.A000.FSLIT.FILESYS.LSN.01. If we detect file latch contention, the best way to determine the exact HFS file causing the problem is with an SVC dump, also collected during a time period in which contention occurred. You will need to dump one of the OMVS data spaces to get the file information.

  
  DUMP COMM=(description of problem)
  Reply to dump WTO, where serverproc is the name of the WebSphere Server                    address space(s)
  JOBNAME=(OMVS,Serverproc),DSPNAME=('OMVS'.SYSZBPX1,'OMVS'.SYSZBPX2),
  SDATA=(CSA,GRSQ,LPA,NUC,PSA,RGN,SQA,TRT,SUM)     
  
  

• Sometimes USS errors can cause performance problems. The USS Ctrace (SYSOMVS) MIN tracing option always records OMVS errors. We can take an SVC dump of the OMVS address space (as described in the previous bullet) and the data spaces and format the SYSOMVS CTRACE. Use IPCS options 7.2.1, suboption D, component SYSOMVS and the TALLY option (default is FULL). Look for trace events of errors in the TALLY report.

• To find delays in applications, collect application performance information
  • SMF 120 records.
  • Jinsight profile

Choose and using diagnosis tools and controls on z/OS

Diagnose problems (using diagnosis tools)