DB2 - Problembeschreibung
Problem IC78000 | Status: Geschlossen |
ALTER TABLESPACE WITH REBALANCE MAY APPEAR TO HANG FOR A LONG TIME BEFORE RETURNING SQL2094W REASON CODE 2 | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problembeschreibung: | |
When a storage path is added to an automatic storage database, and an alter tablespace issued to rebalance the conatiners, DB2 may erroneously conclude that a new container is going to fit into a new path to be used for rebalancing. However, in reality the path does not have enough disk space to accommodate the new container. Following is the sequence of steps, that may lead to this issue: db2 "ALTER DATABASE SAMPLE ADD STORAGE ON '/db2/data/sample/a3'" db2 "ALTER DATABASE SAMPLE ADD STORAGE ON '/db2/data/sample/a3'" db2 connect to SAMPLE db2 "ALTER TABLESPACE TBSP1 REBALANCE" Isuuing the alter database command mentioned above twice, causes DB2 to show 2 identical automatic storage paths, as can be seen in the snapshot below: Number of automatic storage paths = 4 Automatic storage path = /db2/data/sample/a1 Node number = 0 State = In Use Automatic storage path = /db2/data/sample/a2 Node number = 0 State = In Use Automatic storage path = /db2/data/sample/a3 Node number = 0 State = Not In Use Automatic storage path = /db2/data/sample/a3 Node number = 0 State = Not In Use After the last ALTER TABLEPSACE command is issued, since there is not enough space on the storage path just added to accomodate the container, the retry logic in DB2 will keep on attempting to create the new container, during which time the table space will be unaccessible to the end user, who may perceive this situation as a hang. Eventually, SQL2094W reason code 2 will be returned, but this may happen a long time (e.g. tens of minutes) after issuing the ALTER TABLE ... REBALANCE command. During this time, the following error messages might be dumped in the db2diag.log: 2010-10-19-22.08.57.906941+120 I230832A2923 LEVEL: Error (OS) PID : 10293 TID : 81 PROC : db2sysc 0 INSTANCE: db2usrp2 NODE : 000 DB : SAMPLE APPHDL : 0-10932 APPID: *LOCAL.db2usrp2.101019193340 AUTHID : DB2USRP2 EDUID : 81 EDUNAME: db2agent (ARNP) 0 FUNCTION: DB2 Common, OSSe, ossErrorIOAnalysis, probe:100 CALLED : OS, -, write OSERR : ENOSPC (28) "No space left on device" DATA #1 : String, 146 bytes A total of 5 analysis will be performed : - User info - ulimit info - Target file info - I/O attempt - File system Target file handle = 58 DATA #2 : String, 184 bytes Real user ID of current process = 212 Effective user ID of current process = 212 Real group ID of current process = 212 Effective group ID of current process = 212 DATA #3 : String, 353 bytes Current process limits (unit in bytes except for nofiles) : mem (S/H) = unlimited / unlimited core (S/H) = unlimited / unlimited cpu (S/H) = unlimited / unlimited data (S/H) = unlimited / unlimited fsize (S/H) = unlimited / unlimited nofiles (S/H) = 65536 / 65536 stack (S/H) = 8388608 / unlimited rss (S/H) = 0 / 0 DATA #4 : String, 263 bytes Target File Information : Size = 4185948160 Link = No Reference path = N/A Type = 0x8000 Permissions = rw------- UID = 212 GID = 212 Last modified time = 1287518937 DATA #5 : String, 33 bytes I/O attempt not implemented yet. DATA #6 : String, 397 bytes File System Information of the target file : Block size = 1024 bytes Total size = 26430790656 bytes Free size = 0 bytes Total # of inodes = 3110016 FS name = /dev/md/db2p2/dsk/d6 Mount point = /db2/data/arnp/a3 FSID = 22298630 FS type name = ufs DIO/CIO mount opt = None Device type = N/A FS type = 0x9 CALLSTCK: [0] 0xFFFFFFFF7EDBB198 ossLogSysRC + 0x3EC [1] 0xFFFFFFFF7EDACCE4 ossErrorNameMapSystem + 0x1AFC [2] 0xFFFFFFFF791DF6D4 sqloSystemErrorHandler + 0x9DC [3] 0xFFFFFFFF7924971C sqloSetFileSize + 0x1C2C [4] 0xFFFFFFFF7924A650 sqloSetFileSize + 0x2B60 [5] 0xFFFFFFFF79248A64 sqloSetFileSize + 0xF74 [6] 0xFFFFFFFF777A5EF8 __1cbHsqlbServiceAddDMSContainerRequest6FpnOSQdDLB_pfParIoCb_pnM SQdDLB_P OOL_CB_pnQSQdDLB_POOLCONT_CB_pnMSQdDLB_GLOBALS__i_ + 0x5E0 [7] 0xFFFFFFFF778F129C __1cbAsqlbDMSAddContainerRequest6FpnMSQdDLB_POOL_CB_pnQSQdDLB_PO OLCONT_C B_pnMSQdDLB_GLOBALS_pnOSQdDLB_pfParIoCb_bL_i_ + 0x17D4 [8] 0xFFFFFFFF7791578C __1cRsqlbDMSCreatePool6FpnMSQdDLB_POOL_CB_ipnQSQdDLB_POOLCONT_CB _pnMSQdD LB_GLOBALS__i_ + 0x2024 [9] 0xFFFFFFFF7791740C __1cbHsqlbPerformDMSContainerOperations6FpnMSQdDLB_POOL_CB_1LpnQ SQdDLB_P OOLCONT_CB_bpnbASQdDLB_AS_CONT_AND_PATH_INFO_pnMSQdDLB_ + 0x108C The problem only happens for containers whose new size will be larger than the maximum value of the unsigned integer C type, i.e. for containers larger than 4,294,967,295 bytes. This is a integer overflow problem, where DB2 miscaulculates the amount of size required for the creation of the new container. | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * v97fp5 * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to V97fp6 * **************************************************************** | |
Local-Fix: | |
verfügbare FixPacks: | |
DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows | |
Lösung | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 09.08.2011 12.06.2012 12.06.2012 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.7.FP6 | |
Problem behoben lt. FixList in der Version | |
9.7.0.6 |