DB2 - Problembeschreibung
Problem IC88663 | Status: Geschlossen |
HIGH NUMBER OF PREFETCHER REQUESTS CAUSING HIGH SYS% AND PERFORMANCE DEGRADATION | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
Problembeschreibung: | |
During heavy workload, high number of prefetcher requests can cause latch contention which in turn will cause SYS CPU increase and performance impact on running transactions. The latch contention during this time is on prefetcher free list latch: SQLO_LT_SQLB_pfCB__freeListLatch From db2pd -latches collected during the issue, we can see high number of waiters for this latch: 0x070000212508F160 282449 359566 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 593521 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 66545 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 240148 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 190171 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 218614 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 112921 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 115485 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 185929 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 208715 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 234577 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 238165 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 243544 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 0x070000212508F160 282449 249185 sqlbpfgen.C 1441 SQLO_LT_SQLB_pfCB__freeListLatch 1 The stack dumps may look as follows: sqloXlatchConflict + 0x29C sqloXlatchConflict@glue1AC + 0x78 sqlbPFAddFreeRequest__FPP14SQLB_pfRequestP12SQLB_GLOBALS + 0x24 sqlbPFAddFreeRequest__FPP14SQLB_pfRequestP12SQLB_GLOBALS@glue552 + 0x74 sqldmPrefetchList__FP8sqeAgentP8SQLD_CCBPP14SQLB_pfRequesti + 0x3E8 sqldmPrefetchList__FP8sqeAgentP8SQLD_CCBPP14SQLB_pfRequesti@glue EBB + 0x78 sqlriPrefetchRIDs__FP8sqlrr_cbP8sqlri_lfl + 0x33C sqlriPrefetchRIDs__FP8sqlrr_cbP8sqlri_lfl@glue1505 + 0x74 sqlriListFetch__FP8sqlrr_cb + 0x248 sqlriSectInvoke__FP8sqlrr_cbP12sqlri_opparm + 0x28 sqlrr_process_execute_request__FP8sqlrr_cbi + 0xC74 sqlrr_execute__FP14db2UCinterfaceP9UCstpInfo + 0x224 executeSection__10pvmPackageFP5sqlcaUib + 0x548 executeQuery__3PVMFUib + 0x1B4 run__3PVMFv + 0x18C pvm_entry + 0x498 sqloInvokeFnArgs + 0xEC sqloInvokeFnArgs@glue4C3 + 0x78 sqlriInvokerTrusted__FP10sqlri_ufobP21sqlriRoutineErrorIntf + 0x1C8 sqlriInvokeInvoker__FP10sqlri_ufobb + 0xB9C or/and sqloSpinLockReleaseConflict + 0xC0 sqloSpinLockReleaseConflict@glue74 + 0x78 sqlbPFGetFreeRequest__FUiiPP14SQLB_pfRequestP12SQLB_GLOBALS + 0x4 sqlbPFGetFreeRequest__FUiiPP14SQLB_pfRequestP12SQLB_GLOBALS@glue 551 + 0x7C sqldmPrefetchList__FP8sqeAgentP8SQLD_CCBPP14SQLB_pfRequesti + 0x114 sqldmPrefetchList__FP8sqeAgentP8SQLD_CCBPP14SQLB_pfRequesti@glue EBB + 0x78 sqlriPrefetchRIDs__FP8sqlrr_cbP8sqlri_lfl + 0x33C sqlriPrefetchRIDs__FP8sqlrr_cbP8sqlri_lfl@glue1505 + 0x74 sqlriListFetch__FP8sqlrr_cb + 0x248 sqlriSectInvoke__FP8sqlrr_cbP12sqlri_opparm + 0x28 sqlrr_process_execute_request__FP8sqlrr_cbi + 0xC74 sqlrr_execute__FP14db2UCinterfaceP9UCstpInfo + 0x224 executeSection__10pvmPackageFP5sqlcaUib + 0x548 executeQuery__3PVMFUib + 0x1B4 run__3PVMFv + 0x18C pvm_entry + 0x498 sqloInvokeFnArgs + 0xEC sqloInvokeFnArgs@glue4C3 + 0x78 sqlriInvokerTrusted__FP10sqlri_ufobP21sqlriRoutineErrorIntf + 0x1C8 sqlriInvokeInvoker__FP10sqlri_ufobb + 0xB9C | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * All * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to the latest fix pack. * **************************************************************** | |
Local-Fix: | |
No Local Fix | |
verfügbare FixPacks: | |
DB2 Version 10.1 Fix Pack 2 for Linux, UNIX, and Windows | |
Lösung | |
Problem was first fixed in DB2 UDB version 10.1 fix pack 2. | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 28.11.2012 20.12.2012 20.12.2012 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
Problem behoben lt. FixList in der Version | |
10.1.0.2 | |
10.5.0.2 |