RE: Query using (too) much CPU

Johan,

SQL runtime performance can be tuned in many ways, though I can't think of a 
way to truly limit a query to run at low priority...  Honestly, you'd be better 
off getting the query optimizer to help you build index objects that could 
speed up your queries.

Run your job in debug (update production data *yes) and review the joblog for 
index recommendations.

hth,
Eric

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx]On Behalf Of Johan Vangilbergen
Sent: Tuesday, February 13, 2007 9:47 AM
To: midrange-l@xxxxxxxxxxxx
Subject: Query using (too) much CPU


On our 810 V5R2M0, we're having some problems with queries consuming a
lot of CPU, and slowing down all other tasks.

 

These queries originate mainly from 2 sources :

1.      Programs with embedded SQL, which produce statistics over a
specified period of time
2.      An SQL-tool, running on a PC-client, which does inquiries on the
AS400 database through ODBC.

 

The fact now is, that when a user starts a query (which he can define
himself) the system becomes very slow and the query consumes a lot of
CPU, killing all other jobs.

 

My question is : is there a way to prevent these tasks from putting the
AS400 to his knees.  I still want these tasks to be executed, eventually
at a slower rate.  But the essential is that the other jobs should not
suffer under this query.

 

Can anyone point me in the right direction ?

 

 

 

Johan Vangilbergen

 

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