Re: pg_dump makes our system unusable - any way to pg_dump in the middle of the day? (postgres 8.4.4)

On Thu, Feb 24, 2011 at 6:38 PM, Aleksey Tsalolikhin
<atsaloli.tech@gmail.com> wrote:
> In practice, if I pg_dump our 100 GB database, our application, which
> is half Web front end and half OLTP, at a certain point, slows to a
> crawl and the Web interface becomes unresponsive.  I start getting
> check_postgres complaints about number of locks and query lengths.  I
> see locks around for over 5 minutes.
>

I'd venture to say your system does not have enough memory and/or disk
bandwidth, or your Pg is not tuned to make use of enough of your
memory.  The most likely thing is that you're saturating your disk
I/O.

Check the various system statistics from iostat and vmstat to see what
your baseline load is, then compare that when pg_dump is running.  Are
you dumping over the network or to the local disk as well?