MVSFORUMS.com

[mikeg]

I have a CICS transaction that uses 8 seconds of CPU, and I am looking at what can be done to reduce the CPU. I see module DFHSIP has a CSECT of DFHDSSR. This CSECT is using 16.66% of the CPU. Does anyone know what this CSECT does? I have looked at Book Manager, but could not find the description of the CSECT. I am also looking for a description of DFHTRPX 3.85% and DFHDSDS3 1.86%.

[kolusu]

Mike,

DFHSIP (Data Facility Hierachial System Initialization Program) is a CICS initialization program. This pgm is usually invoked before startup of CICS. Is your transaction related to startup of CICS? If it is then you need to make sure that enough data space is available

Hope this helps...

cheers

kolusu
_________________
Kolusu
www.linkedin.com/in/kolusu

[Mike Chantrey]

I'm not sure that kolusu is right about this. I believe that DFHSIP is the main CICS program which is running throughout the lifetime of the CICS service (as well as at initialization). In fact, since this is the program you specified as the top level program in CICS JCL, I don't think it can terminate until CICS does.

DFHDSSR is part of the dispatcher component (see the CICS customization guide for a description of the DFHDSSRX macro which invokes this module), and most (but not all) EXEC CICS commands cause the dispatcher to be invoked; thus you can probably reduce the time spent in this module by eliminating as many EXEC CICS commands as possible, particularly in any inner loops. This may or may not be possible depending on the nature of the code.

I don't think IBM give out details of modules' internal functions generally; DFHDSDS3 will be another dispatcher module, and DFHTRPX should be a trace module. You can eliminate/reduce trace overhead by turning off trace altogether or only tracing selected components.