DB2 - Problem description
Problem IC98938 | Status: Closed |
PANIC IN SQLO_XLATCH::RELEASE CONFLICT WHEN UNLOCKING AN UNLATCHED LOCK | |
product: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problem description: | |
In a federated server utilizing two-phase-commits and LOCK SNAPSHOTS, it is possible for the engine to panic in SQLO_XLATCH with a probe(in db2diag.log) indicating release conflict when unlocking an unlatched lock. snippet from db2diag.log: <timestamp> LEVEL: Severe PID : <my_pid> TID : <my_tid> PROC : db2sysc INSTANCE: <my_inst> NODE : <node> DB : <db_name> APPHDL : <app_hdl> APPID: <my_app_id> AUTHID : <auth_id> EDUID : <eduid> EDUNAME: <edu_name> FUNCTION: DB2 UDB, SQO Latch Tracing, sqlo_xlatch::releaseConflict, probe:10 DATA #1 : String, 27 bytes unlocking an unlatched lock DATA #2 : Pointer, 8 bytes 0x0700000171b69868 DATA #3 : String, 123 bytes { lock = { 0x00000000 [ unlocked ] } identity = SQLQG_F2PC_T::federatedProcessingSnapshotLatch (144) } DATA #4 : Hexdump, 8 bytes 0x0700000171B69868 : 0000 0000 0090 0000 ........ CALLSTCK: (Static functions may not be resolved correctly, as they are resolved to the nearest symbol) [0] 0x090000000D5437D4 pdLog + 0xE0 [1] 0x090000000D95E5F0 pdLog@glue413 + 0x12C [2] 0x090000000DB8CB60 sqloSpinLockReleaseConflict + 0x5C [3] 0x090000000D36A248 sqloSpinLockReleaseConflict@glue73 + 0x78 [4] 0x090000000EE8F608 sqlpm_write_locks_indoubt_tran__FP16sqeLocalDatabaseP8sqeAgentP1 9sqm_snapshot_bufferUiPUiT5P16sqlm_header_info + 0x64C [5] 0x090000000EE8DD14 @92@sqm_snap_db_locks__FPC16sqm_agent_entityRC8sqlo_gmtP19sqm_sn apshot_bufferP16sqeLocalDatabaseP14sqlm_collectedPCcCUiPP15sqlm + 0x564 [6] 0x090000000CD006D0 sqlmonssagnt__FUi13sqm_entity_idP6sqlmaiT1PvP14sqlm_collectedUsT 7P5sqlca + 0xD2C [7] 0x090000000D922EBC sqlmonssbackend__FP12SQLE_DB2RA_T + 0x228 [8] 0x090000000DBDD12C sqlesrvr__FP14db2UCinterface + 0x738 [9] 0x090000000D351B68 sqleMappingFnServer__FP5sqldaP5sqlca + 0x1D0 The stack would look similar to this: <StackTrace> -------Frame------ ------Function + Offset------ 0x090000000066CF54 pthread_kill + 0xD4 0x090000000CD0B4E4 sqloDumpEDU + 0x54 0x090000000CB9B448 sqle_panic__Fv + 0xBC 0x090000000DF49B50 sqle_panic__Fv@glue198 + 0x7C 0x090000000DB8CB68 sqloSpinLockReleaseConflict + 0x64 0x090000000D36A248 sqloSpinLockReleaseConflict@glue73 + 0x78 0x090000000EE8F608 sqlpm_write_locks_indoubt_tran__FP16sqeLocalDatabaseP8sqeAgentP1 9sqm_snapshot_bufferUiPUiT5P16sqlm_header_info + 0x64C 0x090000000EE8DD14 @92@sqm_snap_db_locks__FPC16sqm_agent_entityRC8sqlo_gmtP19sqm_sn apshot_bufferP16sqeLocalDatabaseP14sqlm_collectedPCcCUiPP15sqlm_ dbase_lockP16sqlm_header_info + 0x564 0x090000000CD006D0 sqlmonssagnt__FUi13sqm_entity_idP6sqlmaiT1PvP14sqlm_collectedUsT 7P5sqlca + 0xD2C 0x090000000D922EBC sqlmonssbackend__FP12SQLE_DB2RA_T + 0x228 0x090000000DBDD12C sqlesrvr__FP14db2UCinterface + 0x738 0x090000000D351B68 sqleMappingFnServer__FP5sqldaP5sqlca + 0x1D0 0x090000000D351470 sqlerKnownProcedure__FiPcPiP5sqldaT4P13sqlerFmpTableP8sqeAgentP5 sqlca + 0x344 0x090000000D3503A8 sqlerCallDL__FP14db2UCinterfaceP9UCstpInfo + 0x580 0x090000000D350980 .sqljs_ddm_excsqlstt.fdpr.clone.253__FP14db2UCinterfaceP13sqljDD MObject + 0xE4 0x090000000D50E55C sqljsParseRdbAccessed__FP13sqljsDrdaAsCbP13sqljDDMObjectP14db2UC interface + 0x110 0x090000000D50E204 .sqljsParse.fdpr.clone.234__FP13sqljsDrdaAsCbP14db2UCinterfaceP8 sqeAgentb + 0x6D8 0x090000000D511984 @63@sqljsSqlam__FP14db2UCinterfaceP8sqeAgentb + 0x2C0 0x090000000D667148 @63@sqljsDriveRequests__FP8sqeAgentP14db2UCconHandle + 0xB4 0x090000000D666E38 @63@sqljsDrdaAsInnerDriver__FP18SQLCC_INITSTRUCT_Tb + 0x2D4 0x090000000D6668BC sqljsDrdaAsDriver__FP18SQLCC_INITSTRUCT_T + 0xFC 0x090000000D2E5A3C RunEDU__8sqeAgentFv + 0x280 0x090000000D2E0EA8 EDUDriver__9sqzEDUObjFv + 0xDC 0x090000000D30DAEC sqloEDUEntry + 0x254 </StackTrace> | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * First fixed in Version 9.7 Fix Pack 10. * **************************************************************** | |
Local Fix: | |
This panic can be avoided by turning off FEDERATED processing | |
Solution | |
First fixed in Version 9.7 Fix Pack 10. | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 23.01.2014 16.02.2015 16.02.2015 |
Problem solved at the following versions (IBM BugInfos) | |
9.7.FP10 | |
Problem solved according to the fixlist(s) of the following version(s) | |
9.7.0.10 |