DB2 - Problembeschreibung
Problem IC69252 | Status: Geschlossen |
DB2 V9.5, V9.7 MAY GET SIGSEV WHEN HITTING TIMING HOLE BETWEEN CONCURRENT CONNECTION REQUESTS | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 | |
Problembeschreibung: | |
A sigsev may occur due to a timing issue when concurrent connection requests attempt to acquire and release latches. This issue is caused by a timing hole between a connection that is terminating and a new connection that is coming in. This could also occur when attempting to perform a quiesce database operation. This impacts users on DB2 Version 9.5 and 9.7. One way to diagnose if you have encountered this issue is to review the db2diag.log messages and search for one that displays message about latch conflict with "unlocking an unlatched lock" and "NO_IDENTITY". View the sample output listed below. 2010-04-01-20.59.42.595251+000 I5796499244A1497 LEVEL: Severe PID : 111111 TID : 23138 PROC : db2sysc 0 INSTANCE: db2inst1 NODE : 000 DB : DBROQC6 APPHDL : 0-55171 APPID: 10.1.1.1.51364.10041820575 AUTHID : db2inst1 EDUID : 23138 EDUNAME: db2agent (idle) 0 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 0x0780000001f766e8 DATA #3 : String, 86 bytes { lock = { 0x00000000 [ unlocked ] } identity = NO_IDENTITY (0) } DATA #4 : Hexdump, 8 bytes 0x0780000001F766E8 : 0000 0000 0001 0000 ........ CALLSTCK: [0] 0x09000000081F2634 pdLog@glue32E + 0x128 [1] 0x090000000678B57C sqloSpinLockReleaseConflict + 0x174 [2] 0x0900000006AF5500 sqloSpinLockReleaseConflict@glue7A + 0x74 [3] 0x0900000007977D48 TermDbConnect__16sqeLocalDatabaseFP8sqeAgentP5sqlcai + 0x238 [4] 0x09000000072563D4 HandleStartUsingError__14sqeApplicationFP8sqeAgentP8SQLE_BWAP5sq lcaP22SQLESRSU_STATUS_VECTOR + 0x384 [5] 0x0900000007979B70 AppStartUsing__14sqeApplicationFP8SQLE_BWAP8sqeAgentcT3P5sqlcaPc + 0xFC [6] 0x090000000697425C AppLocalStart__14sqeApplicationFP14db2UCinterface + 0x390 [7] 0x0900000006A6FCF0 sqlelostWrp__FP14db2UCinterface + 0x34 [8] 0x0900000006A6FD6C sqleUCengnInit__FP14db2UCinterfaceUs + 0x24 [9] 0x090000000693AF28 sqleUCagentConnect + 0x27C Stack trace for thread looks similar to : <StackTrace> -------Frame------ ------Function + Offset------ 0x090000000062B81C pthread_kill + 0x88 0x090000000612F52C sqloDumpEDU + 0x48 0x0900000006573974 sqle_panic__Fv + 0x4C 0x09000000064F9E0C sqle_panic__Fv@glue4F1 + 0x74 0x090000000678B584 sqloSpinLockReleaseConflict + 0x17C 0x0900000006AF5500 sqloSpinLockReleaseConflict@glue7A + 0x74 0x0900000007977D48 TermDbConnect__16sqeLocalDatabaseFP8sqeAgentP5sqlcai + 0x238 0x09000000072563D4 ........... </StackTrace> Additional Note: There is also another rare scenario with this timing issue where it's possible for the lock identity to be defined already (instead of NO_IDENTITY"). The db2diag.log message will contain the following keywords: "unlocking an unlatched lock" and "sqeLocalDatabase::dblatch (1)" 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 0x07800000014966e8 DATA #3 : String, 100 bytes { lock = { 0x00000000 [ unlocked ] } identity = sqeLocalDatabase::dblatch (1) } | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * See APAR Description * **************************************************************** * RECOMMENDATION: * * Upgrade to IBM DB2 version 9.5 Fixpack 7 * **************************************************************** | |
Local-Fix: | |
verfügbare FixPacks: | |
DB2 Version 9.5 Fix Pack 7 for Linux, UNIX, and Windows | |
Lösung | |
First Fixed in V9.5 FP7 | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Bug-Verfolgung | |
Vorgänger : APAR is sysrouted TO one or more of the following: IC69276 IC75131 Nachfolger : | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 15.06.2010 10.01.2011 10.01.2011 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.5.FP7 | |
Problem behoben lt. FixList in der Version | |
9.1.0.7 | |
9.5.0.7 |