Re: PostgreSQL 8.4 performance tuning questions

On Thu, Jul 30, 2009 at 10:07 AM, Rauan Maemirov<rauan(at)maemirov(dot)com> wrote:
> Unfortunately had to downgrade back to 8.3. Now having troubles with
> that and still solving them.
>
> For future upgrade, what is the basic steps?
>
>>Was the database analyzed recently?
> Hm... there was smth like auto analyzer in serverlog when i started it
> first time, but i didn't mention that.
> Should I analyze whole db? How to do it?
>
> And how should I change _cost variables?
>
> I/O was very high. at first memory usage grew up and then began to full swap.

There is at least one known case of memory leak 8.4.0. Possibly you
got hit by that or another early adopter bug. I think in your case
it's probably to soon to have upgraded...with 10k connections even
minor annoyances can be real nasty.

I'd wait a few months while in the meantime stage your app on a
testing database and double check the important query plans to make
sure there are no big performance regressions. Each version of pg has
a couple for various reasons.

merlin