Fixes are available
APAR status
Closed as duplicate of another APAR.
Error description
db2 may trap due to memory corruption in statement heap while compiling a SQL if the Real Time Statistics(RTS) is turned ON, i.e Automatic maintenance (AUTO_MAINT) = ON Automatic table maintenance (AUTO_TBL_MAINT) = ON Automatic runstats (AUTO_RUNSTATS) = ON Automatic statement statistics (AUTO_STMT_STATS) = ON When the crash occurs, the db2diag.log may show the memory corruption messages as follows: 2009-09-20-10.37.15.347782+000 E55366A1372 LEVEL: Severe PID : 1318934 TID : 23850 PROC : db2sysc 0 INSTANCE: db2inst1 NODE : 000 DB : DB1 APPHDL : 0-980 APPID: *LOCAL.db2inst1.090920103627 AUTHID : db2inst1 EDUID : 23850 EDUNAME: db2agent (DB1) 0 FUNCTION: DB2 UDB, SQO Memory Management, sqloDiagnoseFreeBlockFailure, probe:999 MESSAGE : Memory validation failure, diagnostic file dumped. DATA #1 : String, 28 bytes Corrupt pool free tree node. DATA #2 : File name, 33 bytes 1318934.23850.mem_diagnostics.txt CALLSTCK: [0] 0x090000000ACBF128 pdLog + 0x88 [1] 0x090000000AA6E8E8 diagnoseMemoryCorruptionAndCrash__13SQLO_MEM_POOLFUlCPCc + 0x250 [2] 0x090000000AA6E5BC diagnoseMemoryCorruptionAndCrash__13SQLO_MEM_POOLFUlCPCc@glue693 + 0x74 [3] 0x090000000AE2575C .MemTreePut__13SQLO_MEM_POOLFP8SMemNodeUlP17SqloChunkSubgroup_fd prpro_clone_83 + 0xC [4] 0x090000000AE2A328 sqlofmblkEx + 0x244 [5] 0x090000000AEAFBC0 sqlofmblkEx@glue687 + 0x74 [6] 0x090000000AEAF738 set_fcsptrs__9sqlnq_ftbFCP9sqlnq_fcs + 0x280 [7] 0x090000000AEAF0BC __ct__9sqlnq_fcsFP9sqlnq_ftbiRiP3locb + 0x1DC [8] 0x090000000AEAE9E4 add_column__9sqlnq_ftbFPiPP9sqlnq_fcsP3loc + 0xB8 [9] 0x090000000AEAA0E0 add_head_exp__9sqlnq_qtbFP9sqlnq_pidiP12sqlnq_stringPUcPiPP9sqln q_qclPP9sqlnq_expT2b + 0xD0 and the stack of the agent thread which reports the corruption might look like: 0x090000000AA6F344 sqloCrashOnCriticalMemoryValidationFailure + 0x1C 0x090000000AA6E8F0 diagnoseMemoryCorruptionAndCrash__13SQLO_MEM_POOLFUlCPCc + 0x258 0x090000000AA6E5BC diagnoseMemoryCorruptionAndCrash__13SQLO_MEM_POOLFUlCPCc@glue693 + 0x74 0x090000000AE2575C .MemTreePut__13SQLO_MEM_POOLFP8SMemNodeUlP17SqloChunkSubgroup_fd prpro_clone_83 + 0xC 0x090000000AE2A328 sqlofmblkEx + 0x244 0x090000000AEAFBC0 sqlofmblkEx@glue687 + 0x74 0x090000000AEAF738 set_fcsptrs__9sqlnq_ftbFCP9sqlnq_fcs + 0x280 0x090000000AEAF0BC __ct__9sqlnq_fcsFP9sqlnq_ftbiRiP3locb + 0x1DC 0x090000000AEAE9E4 add_column__9sqlnq_ftbFPiPP9sqlnq_fcsP3loc + 0xB8 0x090000000AEAA0E0 add_head_exp__9sqlnq_qtbFP9sqlnq_pidiP12sqlnq_stringPUcPiPP9sqln q_qclPP9sqlnq_expT2b + 0xD0 0x090000000AEA942C __ct__9sqlnq_hxpFP9sqlnq_oprP9sqlnq_quniT3P12sqlnq_stringPUcPiPP 9sqlnq_qclRiP3loc + 0x204 0x090000000AEA4BB0 add2output__9sqlnq_qncFP9sqlnq_opriPP9sqlnq_qcl15sqlnq_usageType - 0x224 0x090000000AEA45C0 sqlnq_handle_qnc_sel_star__FP9sqlnq_qunbT2P9sqlnq_oprPiP9sqlnq_q urN42 + 0x474 0x090000000AECC978 sqlnq_sel_star__FP9sqlnq_oprbP9sqlnq_qunPiP9sqlnq_qurN22 + 0x210 0x090000000AECC664 sqlnq_sem_sel_star__FPP8stknode_i10actiontypePUcP3loc + 0xB8 0x090000000AE837A4 sqlnp_smactn__FP8sqlnp_cbi + 0x320 0x090000000AE838C8 sqlnp_parser__FP8sqlnp_cb + 0x7C 0x090000000AF306A8 sqlnp_main__FP12sqlnq_stringsPP9sqlnq_qur + 0x33C 0x090000000AF2DFCC sqlnn_cmpl__FP8sqeAgentP11sqlrrstrings17sqlnn_compileModeT3P14sq lrr_cmpl_enviT7PP9sqlnq_qur + 0x828 0x090000000AEDFAA4 sqlnn_cmpl__FP8sqeAgentP11sqlrrstrings17sqlnn_compileModeT3P14sq lrr_cmpl_env + 0x24 0x090000000AEDC7A4 sqlra_compile_var__FP8sqlrr_cbP14sqlra_cmpl_envPUciUsN54P16sqlra _cached_varPiPUl + 0x60C 0x090000000AF845C8 sqlra_find_var__FP8sqlrr_cbP17sqlra_cached_stmt13sqlra_stmt_idUi T4PUcT4UsUcP14sqlra_cmpl_enviPiT11_T12_N311_T12_P14SQLP_LOCK_INF OPP16sqlra_cached_varT12_PUlb + 0x400 0x090000000ACDF750 sqlra_get_var__FP8sqlrr_cbiT2bPbT5 + 0x440 0x090000000CBE516C sqlrr_prepare__FP14db2UCinterfaceP16db2UCprepareInfo + 0x138 0x090000000B0A9158 sqljs_ddm_prpsqlstt__FP14db2UCinterfaceP13sqljDDMObject + 0x428 0x090000000A52B3EC sqljsParseRdbAccessed__FP13sqljsDrdaAsCbP13sqljDDMObjectP14db2UC interface + 0x10C 0x090000000AD981FC .sqljsParse__FP13sqljsDrdaAsCbP14db2UCinterface_fdprpro_clone_21 6 + 0x278 and the corrupted memory block might look like: 07000013008ffe88 : -- BLOCK: code: 0xdb2cafe0 size: 24 file: sqlnq_ftb.C line: 3962 seq: 30 CSG: 0xfab07000013008f0 -- -- CORRUPT NODE -- 07000013008ffec8 : 00 00 00 00 00 00 00 0d 00 00 00 05 00 00 00 00 ................ 07000013008ffed8 : ff ff ff ff ff ff ff ff 00 00 00 00 00 00 00 0e ................ 07000013008fff68 : -- BLOCK: code: 0xdb2cafe0 size: 96 file: sqlnq_ftb.C line: 7003 seq: 64 CSG: 0xfab07000013008f0 --
Local fix
This issue only exists if Real Time Statistics(RTS) is turned on, i.e Automatic maintenance (AUTO_MAINT) = ON Automatic table maintenance (AUTO_TBL_MAINT) = ON Automatic runstats (AUTO_RUNSTATS) = ON Automatic statement statistics (AUTO_STMT_STATS) = ON To workaround, you can turn off the RTS under the set of above db cfg.
Problem summary
Problem conclusion
Temporary fix
Comments
This APAR is a duplicate of IZ58996
APAR Information
APAR number
IZ62724
Reported component name
DB2 UDB ESE AIX
Reported component ID
5765F4100
Reported release
950
Status
CLOSED DUB
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2009-10-08
Closed date
2010-04-20
Last modified date
2010-10-07
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Applicable component levels
[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSEPGG","label":"Db2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"950","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]
Document Information
Modified date:
07 October 2010