If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

 
Go Back  dBforums > Database Server Software > DB2 > Deadlocks across partitions?

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 01-03-05, 17:13
pzuercher pzuercher is offline
Registered User
 
Join Date: Jan 2005
Posts: 1
Deadlocks across partitions?

Folks,

I have some jobs running 4 wide that open a cursor and then fetch rows from a single DB2 table. This table is partitioned by account number. Somehow, every so often, two of the jobs will collide with -911 deadlock errors, killing one of the jobs, even though they are accessing accounts in distinct partitions.

Has anyone heard of -911 deadlock errors when the data being accessed is in separate partitions?

The cursor does use account number in the WHERE clause.

Please excuse the general nature of this note; any insight is appreciated.
Reply With Quote
  #2 (permalink)  
Old 01-04-05, 00:44
kdima71 kdima71 is offline
Registered User
 
Join Date: Nov 2004
Posts: 23
Hello! I am sorry for my poor English!

Details are necessary (OS, version of DB2, isolation level, sample code and etc.)!

Last edited by kdima71; 01-04-05 at 10:32.
Reply With Quote
  #3 (permalink)  
Old 01-04-05, 01:18
Marcus_A Marcus_A is offline
Registered User
 
Join Date: May 2003
Location: USA
Posts: 5,196
Make sure you check the reason code. RC 2 is deadlock, and RC 68 is lock timeout. They are not the same thing.

If you are only doing selects, you cannot get lock contention since multiple share locks can coexist with eachother without any interference.

Check to see if you are getting lock escalation (db2diag.log) and it might be a good idea to run a snapshot for locks.
__________________
M. A. Feldman
IBM Certified DBA on DB2 for Linux, UNIX, and Windows
IBM Certified DBA on DB2 for z/OS and OS/390
Reply With Quote
  #4 (permalink)  
Old 01-04-05, 10:10
Peter.Vanroose Peter.Vanroose is offline
Registered User
 
Join Date: Sep 2004
Location: Belgium
Posts: 1,079
If those jobs are just reading and not updating the table, make sure that they access the table with the correct isolation level; if necessary, set the isolation level to CS (cursor stability) or even to UR (uncommitted read).

-- Peter.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On