Re: Serious issues with CPU usage

<andris(at)neti(dot)ee> writes:
> i'm having _serious_ issues of postgres hogging up the CPU over time. A graph
> showing this can be seen at http://andri.estpak.ee/cpu0.png .

You really haven't shown us anything that would explain that graph ...
repeated UPDATEs will slow down a little until you vacuum, but not
by the ratio you seem to be indicating. At least not if they're
indexscans. If you've also got sequential-scan queries, and you're
doing many zillion updates between vacuums, the answer is to vacuum
more often. A decent rule of thumb is to vacuum whenever you've updated
more than about 10% of the rows in a table since your last vacuum.

> A VACUUM FULL is a remedy to this problem, but a simple VACUUM isn't.

I find that odd; maybe there's something else going on here. But you've
not given enough details to speculate.

regards, tom lane