On 15 Prosinec 2011, 18:19, Magnus Hagander wrote: > On Thu, Dec 15, 2011 at 18:13, Tomas Vondra <t...@fuzzy.cz> wrote: >> On 15 Prosinec 2011, 17:55, pratikchirania wrote: >>> Hi, >>> >>> I am having a scenario where I get consistent warnings in the pglog >>> folder: >>> >>> 2011-12-11 00:00:03 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:00:14 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:00:24 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:00:31 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:00:44 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:00:52 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:01:03 JST WARNING: pgstat wait timeout >>> 2011-12-11 00:01:11 JST WARNING: pgstat wait timeout >>> >>> This is impacting database performance. >> >> It's rather a sign that the I/O is overloaded, although in some cases it >> may actually be the cause. >> >>> The issue persists even when I use the database minimally. >> >> Yes, because the file is written periodically - twice a second IIRC. If >> the file is large, this may be an issue. What is the pgstat.stat size >> (should be in data/global). > > That was only true prior to 8.4. As of 8.4 it's only written when > necessary, which is usually a lot less than twice / second.
Thanks for the correction. Nevertheless, it would be useful to know what is the size of the file and what is the I/O usage. Pratik, can you post the size of the pgstat.stat file and post a few lines of "iostat -x 1" collected when the "pgstat wait timeout" happens? Tomas -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
