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Old 06-29-06, 10:12
wayneb64 wayneb64 is offline
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Need Help with Lock Escalations

I own a tool which is putting a very heavy load on a database, and I am
getting lock escalation warnings and alarms. I have taken some steps
to mark transactions as unconditional reads to try and make the DBs life
easier, but I was wondering if there was any way to see which tables are
getting the lock escalations so I can narrow down the problem.

I recently added some logging in the DB to monitor exactly what requests
are being asked of the tool, but I think that that addition itself is putting
a heavy load on the DB. I think I am going to cache that info in memory and
load it into the DB at regular intervals to ease that load.

Any help/advice on tracking down locking issues would be appreciated.

Thanks,
Wayne
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Old 06-29-06, 11:11
n_i n_i is offline
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Quote:
Originally Posted by wayneb64
I was wondering if there was any way to see which tables are
getting the lock escalations so I can narrow down the problem.
Try "GET SNAPSHOT FOR LOCKS..."
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Old 06-29-06, 16:07
wayneb64 wayneb64 is offline
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Thanks, I was able to use:

db2 get snapshot for locks on dbname | grep "Table Name"
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Old 06-29-06, 18:11
Marcus_A Marcus_A is offline
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For most databases, you should increase the LOCKLIST which has a default that is too low. This will help reduce the lock escalation.

db2 connect to sample

db2 update db cfg using LOCKLIST 4096
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