|
Problem IC75868
|
Status: Closed |
DB2 MIGHT ENCOUNTER 'DEADLOCK' ERROR WHEN PERFORMING TWO DROP TABLE STATEMENTS SIMULTANEOUSLY. |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
Deadlocks on system catalog may occur when concurrently perform
two DROP TABLE statements on two different tables with similar
namings and dependent views defined on them.
To identify the problem, you need to use DB2 event monitor to
collect detailed information for deadlocks.
When the deadlock error occurs, in the event monitor output you
will see the following entries:
=============================================
Table of lock waited on : SYSVIEWDEP
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: X - Exclusive
Mode application requested on lock: S - Share
Text : drop table NEWTON.T1
Table of lock waited on : SYSTABAUTH
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: U - Update
Mode application requested on lock: X - Exclusive
Text : drop table NEWTON.T2
=============================================
or
=============================================
Table of lock waited on : SYSVIEWS
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: U - Update
Mode application requested on lock: U - Update
Text : drop table NEWTON.T1
Table of lock waited on : SYSVIEWS
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: X - Exclusive
Mode application requested on lock: U - Update
Text : drop table NEWTON.T2
=============================================
or
=============================================
Table of lock waited on : SYSVIEWS
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: U - Update
Mode application requested on lock: X - Exclusive
Text : drop table NEWTON.T1
Table of lock waited on : SYSVIEWS
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: U - Update
Mode application requested on lock: U - Update
Text : drop table NEWTON.T2
=============================================
or
=============================================
Table of lock waited on : SYSTABAUTH
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: U - Update
Mode application requested on lock: U - Update
Text : drop table NEWTON.T1
Table of lock waited on : SYSTABAUTH
Schema of lock waited on : SYSIBM
Type of lock: Row
Mode of lock: X - Exclusive
Mode application requested on lock: U - Update
Text : drop table NEWTON.T2
============================================= |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* All users of DB2 Version 9.5 on Linux, Unix and Windows *
* platforms running DROP TABLE statements concurrently. *
****************************************************************
* PROBLEM DESCRIPTION: *
* Deadlocks on system catalog may occur when concurrently *
* perform two DROP TABLE statements on two different tables *
* with similar namings and dependent views defined on them. *
* *
* To identify the problem, you need to use DB2 event monitor *
* to collect detailed information for deadlocks. *
* When the deadlock error occurs, in the event monitor output *
* you will see the following entries: *
* ============================================= *
* Table of lock waited on : SYSVIEWDEP *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: X - Exclusive *
* Mode application requested on lock: S - Share *
* Text : drop table NEWTON.T1 *
* *
* Table of lock waited on : SYSTABAUTH *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: U - Update *
* Mode application requested on lock: X - Exclusive *
* Text : drop table NEWTON.T2 *
* ============================================= *
* or *
* ============================================= *
* Table of lock waited on : SYSVIEWS *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: U - Update *
* Mode application requested on lock: U - Update *
* Text : drop table NEWTON.T1 *
* *
* Table of lock waited on : SYSVIEWS *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: X - Exclusive *
* Mode application requested on lock: U - Update *
* Text : drop table NEWTON.T2 *
* ============================================= *
* or *
* ============================================= *
* Table of lock waited on : SYSVIEWS *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: U - Update *
* Mode application requested on lock: X - Exclusive *
* Text : drop table NEWTON.T1 *
* *
* Table of lock waited on : SYSVIEWS *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: U - Update *
* Mode application requested on lock: U - Update *
* Text : drop table NEWTON.T2 *
* ============================================= *
* or *
* ============================================= *
* Table of lock waited on : SYSTABAUTH *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: U - Update *
* Mode application requested on lock: U - Update *
* Text : drop table NEWTON.T1 *
* *
* Table of lock waited on : SYSTABAUTH *
* Schema of lock waited on : SYSIBM *
* Type of lock: Row *
* Mode of lock: X - Exclusive *
* Mode application requested on lock: U - Update *
* Text : drop table NEWTON.T2 *
* ============================================= *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 Version 9.5 FixPak 9 or higher levels. *
**************************************************************** |
| Local Fix: |
Perform the two DROP TABLE statements sequentially. |
| available fix packs: |
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First fixed in DB2 Version 9.5 FixPak 9. |
| Workaround |
Perform the two DROP TABLE statements sequentially. |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC76305
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 18.04.2011
07.03.2012
07.03.2012 |
| Problem solved at the following versions (IBM BugInfos) |
9.0.,
9.5.
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.5.0.9
|
 |
