DB2 - Problembeschreibung
Problem IC77298 | Status: Geschlossen |
APPLICATION SHARED MEMORY (APPSHRH) MIGHT LEAK WHEN ADDING ROWS TO MDC TABLES. | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 | |
Problembeschreibung: | |
Application shared memory (appshrh) might leak when inserting rows to MDC tables. This symptom could be perceived by virtue of db2pd -db <db_name> -memblocks info. 1st Round: Top memory consumers in AppCtl memory set: PoolID PoolName TotalSize(Bytes) %Bytes TotalCount %Count LOC File 20 appshrh 100904064 93.40 788313 72.06 3450 1560397958 2nd Round: Top memory consumers in AppCtl memory set: PoolID PoolName TotalSize(Bytes) %Bytes TotalCount %Count LOC File 20 appshrh 143394048 95.33 1120266 79.21 3450 1560397958 3rd Round: Top memory consumers in AppCtl memory set: PoolID PoolName TotalSize(Bytes) %Bytes TotalCount %Count LOC File 20 appshrh 479587200 98.43 3746775 92.31 3450 1560397958 When an insert into an MDC table occurs, the composite block index is probed for the logical cell corresponding to the dimension values of the record to be inserted. To improve the performance of a transaction inserting multiple rows into an MDC, a cache of cell values is maintained to quickly find the target cell for the next insert without having to probe the composite block index. The allocated memory should be freed at the end of a transaction or when an application terminates. But there is a problem where DB2 does not free the entire list. | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * Application shared memory (appshrh) might leak when * * inserting * * rows to MDC tables. * * * * * * * * This symptom could be perceived by virtue of db2pd -db * * <db_name> * * -memblocks info. * * * * * * * * 1st Round: * * * * Top memory consumers in AppCtl memory set: * * * * PoolID PoolName TotalSize(Bytes) %Bytes TotalCount * * %Count LOC File * * * * 20 appshrh 100904064 93.40 788313 * * * * 72.06 3450 1560397958 * * * * * * * * 2nd Round: * * * * Top memory consumers in AppCtl memory set: * * * * PoolID PoolName TotalSize(Bytes) %Bytes TotalCount * * %Count LOC File * * * * 20 appshrh 143394048 95.33 1120266 * * * * 79.21 3450 1560397958 * * * * * * * * 3rd Round: * * * * Top memory consumers in AppCtl memory set: * * * * PoolID PoolName TotalSize(Bytes) %Bytes TotalCount * * %Count LOC File * * * * 20 appshrh 479587200 98.43 3746775 * * * * 92.31 3450 1560397958 * * * * * * * * When an insert into an MDC table occurs, the composite block * * * * index is probed for the logical cell corresponding to the * * * * dimension values of the record to be inserted. To improve * * the * * performance of a transaction inserting multiple rows into an * * * * MDC, a cache of cell values is maintained to quickly find * * the * * target cell for the next insert without having to probe the * * * * composite block index. * * * * * * * * The allocated memory should be freed at the end of a * * transaction * * or when an application terminates. But there is a problem * * where * * DB2 does not free the entire list. * **************************************************************** * RECOMMENDATION: * * Upgrade to v9.5 FP9 * **************************************************************** | |
Local-Fix: | |
Restart the database to free the leaked memory in appshrh. | |
verfügbare FixPacks: | |
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows | |
Lösung | |
This issue will be addressed in v9.5 FP9. And the appshrh memory leak will be alleivated when inserting rows to MDC tables. | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Bug-Verfolgung | |
Vorgänger : APAR is sysrouted TO one or more of the following: IC77375 IC77376 Nachfolger : | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 01.07.2011 12.02.2012 12.02.2012 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.5.FP9 | |
Problem behoben lt. FixList in der Version | |
9.5.0.9 |