Re: suggestion: log_statement = sample

On Mon, 2009-07-20 at 13:24 -0400, Bill Moran wrote:
> In response to "Greg Sabino Mullane" <greg@turnstep.com>:
> >
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> >
> > >> In my experience, I've found that enabling full logging for a short time
> > >> (perhaps a few hours) gathers enough data to run through tools like
> > >> pgFouine and find problem areas.
> >
> > > It is not possible for us. Logging millions of statements take too much time.
>
> This is a ridiculous statement.

No it isn't.

>   In actual practice, full query logging
> is 1/50 the amount of disk I/O as the actual database activity.  If your
> systems are so stressed that they can't handle another 2% increase, then
> you've got bigger problems lurking.

It depends on the system. I have seen even big systems take a huge hit
by full logging due to transactional velocity.

Joshua D. Drake

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