IBM Support

Logger and CMAS address space hang causing CICS regions to wait on CPSM

Troubleshooting


Problem

You experience hangs in the logger address space and the CICSPlex SM address space (CMAS). Your CICS terminal owning region (TOR) and application owning regions (AORs) appear to be waiting on CICSPlex SM (CPSM). At shutdown, the CMAS region disconnects from the logstream and an automatic off-load to DASD is done.

Symptom

The sequence of events for this problem are as follows:

  1. Logger address space hangs.
  2. CMAS hangs.
  3. TOR and 2 AORs stall (appear to be waiting on CPSM).
  4. There are 4 CMAS regions and DFHLOG for two of these CMASs off-load to DASD and it does not off-load for the other 2 CMAS regions.
  5. At shutdown, the CMAS region disconnects from the logstream. Once everything is disconnected, an automatic off-load is done which takes 20 minutes.

Cause

System initialization table (SIT) parameter AKPFREQ was defined too large and the logstreams were defined too small.

Resolving The Problem

Change AKPFREQ from the default of 4000 to a smaller value like AKPFREQ=500 to allow CICS to trim the logstream more often. Also, consider increasing the size of the logstreams.

Following is a list of the BEFORE and AFTER sizes for the CICS TS logstreams being used in this particular case:
..........................................................................................................
BEFORE:
STRUCTURE NAME(LOG_DFHLOG_00B) SIZE(100000)
INITSIZE(50000)
REBUILDPERCENT(1)
PREFLIST(CF02, CF01)
STRUCTURE NAME(LOG_DFHSHUNT_00B) SIZE(100000)
INITSIZE(50000)
REBUILDPERCENT(1)
PREFLIST(CF02, CF01)

AFTER:
STRUCTURE NAME(LOG_DFHLOG_00B) SIZE(200000)
INITSIZE(200000)
REBUILDPERCENT(1)
PREFLIST(CF02, CF01)
STRUCTURE NAME(LOG_DFHSHUNT_00B) SIZE(100000)
INITSIZE(25000)
REBUILDPERCENT(1)
PREFLIST(CF02, CF01)

BEFORE:
DEFINE STRUCTURE NAME(LOG_DFHLOG_00B) LOGSNUM(100)
MAXBUFSIZE(64000) AVGBUFSIZE(2048)
DEFINE STRUCTURE NAME(LOG_DFHSHUNT_00B) LOGSNUM(100)
MAXBUFSIZE(64000) AVGBUFSIZE(4096)

AFTER:
DEFINE STRUCTURE NAME(LOG_DFHLOG_00B) LOGSNUM(20)
MAXBUFSIZE(64000) AVGBUFSIZE(2048)
DEFINE STRUCTURE NAME(LOG_DFHSHUNT_00B) LOGSNUM(20)
MAXBUFSIZE(64000) AVGBUFSIZE(4096)

BEFORE:
DEFINE LOGSTREAM NAME(SYSB.DFHLOG.MODEL) MODEL(YES)
STRUCTNAME(LOG_DFHLOG_00B) LS_STORCLAS(SYSTEM) HLQ(SYS2)
STG_DUPLEX(YES) DUPLEXMODE(COND) STG_STORCLAS(SYSTEM)
LOWOFFLOAD(75) HIGHOFFLOAD(95)
DEFINE LOGSTREAM NAME(SYSB.DFHSHUNT.MODEL) MODEL(YES)
STRUCTNAME(LOG_DFHSHUNT_00B) LS_STORCLAS(SYSTEM) HLQ(SYS2)
STG_DUPLEX(YES) DUPLEXMODE(COND) STG_STORCLAS(SYSTEM)

AFTER:
DEFINE LOGSTREAM NAME(SYSB.DFHLOG.MODEL) MODEL(YES)
STRUCTNAME(LOG_DFHLOG_00B) LS_STORCLAS(SYSTEM) HLQ(SYS2)
STG_DUPLEX(YES) DUPLEXMODE(COND) STG_STORCLAS(SYSTEM)
LOWOFFLOAD(75) HIGHOFFLOAD(95) LS_SIZE(64000)
DEFINE LOGSTREAM NAME(SYSB.DFHSHUNT.MODEL) MODEL(YES)
STRUCTNAME(LOG_DFHSHUNT_00B) LS_STORCLAS(SYSTEM) HLQ(SYS2)
STG_DUPLEX(YES) DUPLEXMODE(COND) STG_STORCLAS(SYSTEM)
LS_SIZE(64000)

{"0":{"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Component":"CICSPLEX CMAS","Platform":[{"code":"PF035","label":"z\/OS"}],"Version":"4.2;4.1;3.2;3.1","Edition":"","Line of Business":{"code":"LOB35","label":"Mainframe SW"}},"1":{"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Component":"Logger Domain","Platform":[{"code":"PF035","label":"z\/OS"}],"Version":"4.2;4.1;3.2;3.1","Edition":"","Line of Business":{"code":"LOB35","label":"Mainframe SW"}},"192":{"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Line of Business":{"code":"LOB35","label":"Mainframe SW"}},"2":null,"3":null,"4":null,"5":null,"6":null,"7":null,"8":null,"9":null,"10":null,"11":null,"12":null,"13":null,"14":null,"15":null,"16":null,"17":null,"18":null,"19":null,"20":null,"21":null,"22":null,"23":null,"24":null,"25":null,"26":null,"27":null,"28":null,"29":null,"30":null,"31":null,"32":null,"33":null,"34":null,"35":null,"36":null,"37":null,"38":null,"39":null,"40":null,"41":null,"42":null,"43":null,"44":null,"45":null,"46":null,"47":null,"48":null,"49":null,"50":null,"51":null,"52":null,"53":null,"54":null,"55":null,"56":null,"57":null,"58":null,"59":null,"60":null,"61":null,"62":null,"63":null,"64":null,"65":null,"66":null,"67":null,"68":null,"69":null,"70":null,"71":null,"72":null,"73":null,"74":null,"75":null,"76":null,"77":null,"78":null,"79":null,"80":null,"81":null,"82":null,"83":null,"84":null,"85":null,"86":null,"87":null,"88":null,"89":null,"90":null,"91":null,"92":null,"93":null,"94":null,"95":null,"96":null,"97":null,"98":null,"99":null,"100":null,"101":null,"102":null,"103":null,"104":null,"105":null,"106":null,"107":null,"108":null,"109":null,"110":null,"111":null,"112":null,"113":null,"114":null,"115":null,"116":null,"117":null,"118":null,"119":null,"120":null,"121":null,"122":null,"123":null,"124":null,"125":null,"126":null,"127":null,"128":null,"129":null,"130":null,"131":null,"132":null,"133":null,"134":null,"135":null,"136":null,"137":null,"138":null,"139":null,"140":null,"141":null,"142":null,"143":null,"144":null,"145":null,"146":null,"147":null,"148":null,"149":null,"150":null,"151":null,"152":null,"153":null,"154":null,"155":null,"156":null,"157":null,"158":null,"159":null,"160":null,"161":null,"162":null,"163":null,"164":null,"165":null,"166":null,"167":null,"168":null,"169":null,"170":null,"171":null,"172":null,"173":null,"174":null,"175":null,"176":null,"177":null,"178":null,"179":null,"180":null,"181":null,"182":null,"183":null,"184":null,"185":null,"186":null,"187":null,"188":null,"189":null,"190":null,"191":null}

Product Synonym

CICSPlex SM CICSPlexSM CPSM CP/SM CICS/TS CICS TS CICS Transaction Server

Document Information

Modified date:
22 February 2023

UID

swg21025060

Page Feedback