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vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

Hi,

I have an abend due to dead lock -911 as two jobs are simultaneously accessing the same database. I want to know what are the things that I can do for preventing this apart from making the SCHEDULING changes

vkphani · Intermediate Joined: 05 Sep 2003 Posts: 483 Topics: 48

vijaykumar,
check the below link.
http://www.mvsforums.com/helpboards/viewtopic.php?t=5542&highlight=avoid+deadlock

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

Hi,

One of my program does 3 uncommited reads, 2 updates without hold and insert against a table X when a second program tries to do a read without uncommited read the second program is failing with -911. Please let me know what i can do to prevent this problem from happening

vivek1983 · Intermediate Joined: 20 Apr 2006 Posts: 222 Topics: 24

vijayakumar8303,

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

Hi,

I did not try for that but I see that in the second program previously there was an uncommited read a long back but right now it has been commented out. I uncomment that will that work?

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

If I uncomment that portion of reading the table with uncommited read in the second program. Will that workout?

vivek1983 · Intermediate Joined: 20 Apr 2006 Posts: 222 Topics: 24

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

Hi Vivek,

Thanks a lot. Have one similar kind of issue Program A is doing insert into TABLE X and program B is doing two selects wtih HOLD using cursor and 2 updates. I am having probelem with the program B abending with -911. Please let me know how we can fix this.

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

hi can anybody with the second one above

vijayakumar8303 · Beginner Joined: 21 Oct 2005 Posts: 26 Topics: 15

Hi For the first one my DBA is suggesting me to COMMIT my updates in program A oftern. I want to know how would it help me solving -911.

jsharon1248 · Posted: Mon Oct 29, 2007 11:14 am Post subject:

When you issue a COMMIT, you are telling DB2 that you are done with a unit of work and you want to make your changes permanent. Several actions take place when you issue a COMMIT, one of them being that DB2 releases locks on resources that you've updated. By releasing the locks, you're increasing concurrency. However, there is a cost incurred for each COMMIT. So you want to COMMIT frequently if one of your goals is to improve concurrency, but not so frequently that the cost of the COMMITs has a detrimental effect on your process. If your DBA is telling you to increase your COMMIT frequency, that's what you need to do. Ask the DBA for a target COMMIT frequency and shoot for that.