Re: high user cpu, massive SELECTs, no io waiting problem

Thomas Pöhler wrote:
> We are running a biweekly downtime where we do a complete reindex and vaccum full. We cannot identify certain queries
causingthis. 

If you feel that you need VACUUM FULL, either something terribly wrong
has happened, or someone has gotten confused.  In both cases it's
unlikely you want to keep doing that.  See
http://wiki.postgresql.org/wiki/VACUUM_FULL for a nice document leading
through figuring what to do instead.

Note that if you have a database that fits in RAM, but is filled with
the sort of index bloat garbage that using VACUUM FULL will leave
behind, it will cause excessive CPU use when running queries.  If you
already have planned downtime, you really should try to use use CLUSTER
instead, to remove that from the list of possible causes for your issue.

--
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
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