DB2 - Problem description
Problem IC92805 | Status: Closed |
FIX EMP CHAIN WALKING CODE IN INCREMENTAL BACKUP CODE PATH | |
product: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
Problem description: | |
Incremental backup with tablespaces that have a very large number of non-headered pages (ie. type lob, clob, etc), it can fail with a -902 error. Stack traces will indicate sqlbMapIndirectEMPs, and diagprobes regarding bad page reads might occur... Example Stack 0] 0x00002AC7188E9842 pdLog + 0x230 [1] 0x00002AC719100E68 _Z19sqlbGetPageFromDiskP11SQLB_FIX_CBi + 0x1754 [2] 0x00002AC718E39940 _Z7sqlbfixP11SQLB_FIX_CB + 0x4B70 [3] 0x00002AC7182E0C0E _Z11sqlbFixPageP11SQLB_FIX_CBiji + 0x33A [4] 0x00002AC718EDB11D _Z19sqlbMapIndirectEMPsP12SQLB_GLOBALSP11SQLB_FIX_CBjPcjP16SQLB_ OBJECT_DESCP12SQLB_POOL_CB + 0x1F1 [5] 0x00002AC718EDBCE2 _Z24sqlbMapLongObjectExtentsP12SQLB_GLOBALStPPcPj + 0x884 [6] 0x00002AC71A47F88C _Z12sqlubReadDMSP14SQLU_BUFMAN_CB + 0x89C [7] 0x00002AC71A47C5B4 _Z18sqlubBMProcessDataP14SQLU_BUFMAN_CB + 0x9B8 [8] 0x00002AC71A47A750 _Z8sqlubbufP8sqeAgent + 0xA90 [9] 0x00002AC7198E55D6 _Z26sqleSubCoordProcessRequestP8sqeAgent + 0x1AC [10] 0x00002AC71991FA79 _ZN8sqeAgent6RunEDUEv + 0x3EB [11] 0x00002AC71ECAC58C _ZN9sqzEDUObj9EDUDriverEv + 0x17C [12] 0x00002AC71ECAC1B4 _Z10sqlzRunEDUPcj + 0x26 [13] 0x00002AC71C4A6DC3 sqloEDUEntry + 0x971 [14] 0x00002AC7167692A3 /lib64/libpthread.so.0 + 0x62A3 [15] 0x00002AC7252116DD __clone + 0x6D Example DiagProbe 2013-05-14-19.42.48.963713-240 I187893E6851 LEVEL: Warning PID : 3915 TID : 47035097016640 KTID : 6420 PROC : db2sysc INSTANCE: shawnrr NODE : 000 DB : EMP1 APPHDL : 0-76 APPID: *LOCAL.shawnrr.130514234237 AUTHID : SHAWNRR HOSTNAME: hotellnx99 EDUID : 299 EDUNAME: db2bm.277.1 (EMP1) FUNCTION: DB2 UDB, buffer pool services, sqlbGetPageFromDisk, probe:932 MESSAGE : ZRC=0x87020036=-2029912010=SQLB_BADHDR "Bad Page Header" DIA8547C An error occurred in a database page header. DATA #1 : String, 39 bytes Page from disk doesn't match obj or BPD DATA #2 : Page header, PD_TYPE_SQLB_PAGE_HEAD, 48 bytes ... The number of pages required to encounter this problem is based on both the page size and the extent size, with the issue being more likely to be seen if both page size and extent size are small. The issue requires there to be Level 2 EMP pages created to map the pages in the tablespace which is a factor of the afforementioned conditions. As an example for 4K pages and an extent size of 2 (the smallest possible combo), one requires a minimum of 3939970 pages to have the possibility of seeing this problem. For an 8K page, the number of pages increases to 16297114. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * Incremental backup users with lob objects and very large * * numbers of used pages in tablespace * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade product to latest fixpac. * **************************************************************** | |
Local Fix: | |
Move to latest fixpack. | |
available fix packs: | |
DB2 Version 10.1 Fix Pack 3 for Linux, UNIX, and Windows | |
Solution | |
Fixed in this fixpac of db2. New behavior is that incremental backups will succeed | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 04.06.2013 29.08.2014 29.08.2014 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) | |
10.1.0.3 | |
10.1.0.3 |