DB2 - Problembeschreibung
Problem IC90557 | Status: Geschlossen |
STMM BUFFERPOOL MINIMUM NORMAL PAGE AREA AND CONFIGURED BLOCK PAGE AREA ARE NOT MAINTAINED ON ACTIVATION WITH SCALE BACK | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
Problembeschreibung: | |
STMM normally maintains a minimum number of normal bufferpool pages (1000 at this time). This is on top of any configured block page area, which STMM does not tune. On database activation, scaling back may occur when memory is constrained. This process only attempts to maintain an overall size of 1000 for a bufferpool, which may compromise the configuration when there is a block page area configured. The following conditions may result in performance degradation and SQL1218 errors. 1. The bufferpool may initialize with a very small number of normal pages (as low as 32). STMM will try to increase this to the normal minimum size on the next tuning cycle. 2. The block page area may be initialized with less than the configured value. This condition will persist during the current activation as STMM does not tune the block page area. 3. In an STMM/HADR environment, STMM does not actively tune the secondary. If the scaling back occurs on the secondary, the condition of having a small number of normal pages will persist, potentially leading to failures hadr replay processing, resulting in the secondary database marked bad. Since STMM is not tuning, any scaling back on the secondary will also be persistent (configuration changes are written to disk and will be effective on the next activation). Example db2diag.log messages showing scaling back with a block page area configured: 2012-10-30-10.03.31.350919-240 I31939A505 LEVEL: Info PID : 8585406 TID : 1814 PROC : db2sysc 0 INSTANCE: mcornish NODE : 000 DB : TEST APPHDL : 0-42 APPID: *LOCAL.mcornish.121030140331 AUTHID : MCORNISH EDUID : 1814 EDUNAME: db2agent (TEST) 0 FUNCTION: DB2 UDB, buffer pool services, sqlbScaleAutoBPsByFactor, probe:35 MESSAGE : Altering bufferpool "BP1" From: "20000"<automatic> To: "1000"<automatic> 2012-10-30-10.03.31.351426-240 E32445A837 LEVEL: Warning PID : 8585406 TID : 1814 PROC : db2sysc 0 INSTANCE: mcornish NODE : 000 DB : TEST APPHDL : 0-42 APPID: *LOCAL.mcornish.121030140331 AUTHID : MCORNISH EDUID : 1814 EDUNAME: db2agent (TEST) 0 FUNCTION: DB2 UDB, buffer pool services, sqlbSetNumSlotsAndNBPForNewRTBPDef, probe:20 MESSAGE : ADM6069W Buffer pool "BP1" (ID "2") has a NUMBLOCKPAGES value of "10000" which exceeds the maximum supported value for a buffer pool of this size. The NUMBLOCKPAGES value for this buffer pool has been reduced to "980" for its current activation. The value of NUMBLOCKPAGES can be permanently changed by using the ALTER BUFFERPOOL SQL statement. | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * Systems with block-based bufferpools and where self-tuning * * (STMM tuning) of those bufferpools is enabled * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 Version 10.1 Fix Pack 3 * **************************************************************** | |
Local-Fix: | |
verfügbare FixPacks: | |
DB2 Version 10.1 Fix Pack 3 for Linux, UNIX, and Windows | |
Lösung | |
Problem first fixed in DB2 Version 10.1 Fix Pack 3 | |
Workaround | |
see Local Fix | |
Bug-Verfolgung | |
Vorgänger : APAR is sysrouted TO one or more of the following: IC95210 Nachfolger : | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 28.02.2013 04.12.2013 04.12.2013 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
Problem behoben lt. FixList in der Version | |
10.1.0.3 | |
10.1.0.3 |