topic Re: DB disk IO problems - deathstar query in Server Management - Systems Insight Manager

DB disk IO problems - deathstar query

jkarlsmyr_epi — Tue, 15 Apr 2014 13:33:39 GMT

Hi Forum,

Why is this query at the top of the leaderboard over most resource consuming tasks in my DB-server?

SELECT trapItems.trap_id, RTRIM(trap_name), enabled_flag, trapItems.sev_vb FROM trapItems,trapItemsEx WHERE trapItems.trap_id = trapItemsEx.trap_id AND trap_generic_id = @P0

It is since this thursday continuously generating 60-80MB/s in disk access, why o why is this happening?

Any ideas of how to kill this deathstar?

Best Regards,
Johannes

Re: DB disk IO problems - deathstar query

jkarlsmyr_epi — Wed, 16 Apr 2014 06:50:55 GMT

Hi,

as far as i can see, database file I/O more then trippled since last thursday. We have not added the tripple amount of objects and actually done no additional configurations at all.

I can see that the query executes is as intended, but what is strange is the disk I/O. Is there any way to make this deathstar query happen less often? The SIM DB is now our top contender on this particular storage array which is odd since it more or less does nothing except for monitoring hardware alerts.

Best Regards,

Johannes

Re: DB disk IO problems - deathstar query

jkarlsmyr_epi — Wed, 16 Apr 2014 11:28:13 GMT

Aight,

restarting any and all SIM services did the trick and IO settled, as long as the services were turned off of course, as soon as SIM loaded its ray gun DB file I/O got aggressive again.

Actually restarting the SQL-service did the trick for definite. I have looked through at what could have got stuck but found absolutely nothing.

BR,

Johannes

Re: DB disk IO problems - deathstar query

jkarlsmyr_epi — Tue, 24 Jun 2014 07:09:20 GMT

This obnixious behaviour keeps coming back over and over again, this is really really bad for my SAN.

Any ideas?

BR,

johannes

Re: DB disk IO problems - deathstar query

Andrew_Haak — Tue, 24 Jun 2014 07:54:53 GMT

Hello,

Did you set the Database logging to simple ? If it is set to Full the logfiles tend to explode. An other thing could be that you get a lot of events. The combination is lethal.

I've seen the SIM server using the full 100Mb link to the SQL server. You could also do a database check in the comamdnline on the SIM server type MXCONFIGREPO -c. for a database check. If you see corruption use the -f option to fix your database errors.

Kind regards,

Andrew