Re: Re: Red Hat to support PostgreSQL

> : In a sense threads were a solution to a process bloating problem.
> : Linux/BSD have much lighter processes and hence work better for
> : PostgreSQL.  Again, this is only a guess.
> :
> : MySQL does more stuff with threads while PostgreSQL switches process
> : because each backend is a process.
>
> Does more stuff with threads?  It does all stuff with threads.  Your
> guess was our guess, which is why we tried shoving the thing over to a
> Linux box.  Now if I only I could figure out why kernel CPU usage keeps
> going up incrementally over time (went from roughly a 5% average to a
> 16% average in two days) the more we run the system.  All signs are
> pointing to postgres.
>
> VACUUM ANALYZE-ing the tables used to reduce it back down, but now, it
> doesn't appear to be as effective (might go from 16% back down to
> 13%).  Anyone know what causes that, and better yet, anyone know how to
> fix it?  We see similar behavior under Solaris.

My only guess is index growth.  We don't reclaim disk space used by
indexes after data removal.  You have to drop/recreate the index.  It is
on the TODO list.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
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