DB2 - Problembeschreibung
Problem IC83287 | Status: Geschlossen |
PERFORMANCE PROBLEM WHEN DB2READLOG API CHECKING CONTENT OF REGISTER VARIABLE. | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problembeschreibung: | |
The way db2ReadLog API checking content of register variable on disk may cause performance impact, since db2ReadLog may not cache the value of register variable in memory. Please note that the register variable will be checked regardless of it is set or not set. One of the victim for this non-cached register variable is application that invokes db2ReadLog API, for eg, SQL-Replication capture or Q-Replication capture. To verify this performance problem, stack trace is helpful. The command "db2pd -stack all -repeat" or "db2pd -stack <eduid>" can generate stack files. The generated stack files can be found under DIAGPATH. Below is a sample stack we have found. _global_lock_common _rec_mutex_lock _getpwnam_shadow_r _posix_getpwnam_shadow_r getpwnam_r sqloGetUserAttribByName EnvGetHomePath EnvKeyName EnvPrfOpen sqloGetEnvUnCached sqlp_AsyncLogReadAPI sqlpReadLogInternalAPI sqlpReadLogDRDA sqlerKnownProcedure sqlerCallDL The above stack is collected from db2agent thread which is serving for application calling db2ReadLog. The function sqloGetEnvUnCached is the key point. If sqloGetEnvUnCached can be observed for several times in multiple iterations of stack trace, then this performance problem is being hit. | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * Applications calling db2ReadLog API. * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Update to DB2 version 9.7 fixpack 7 or later fixpacks. * **************************************************************** | |
Local-Fix: | |
verfügbare FixPacks: | |
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows | |
Lösung | |
The problem is fix in DB2 version 9.7 fixpack 7. | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 10.05.2012 20.10.2012 20.10.2012 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.7.FP7 | |
Problem behoben lt. FixList in der Version | |
9.7.0.7 |