Josh Berkus <j...@agliodbs.com> writes:
>> Rather, what you need to be thinking about is how
>> come vacuum seems to be making lots of pages dirty on only one of these
>> machines.

> This is an anti-wraparound vacuum, so it could have something to do with
> the hint bits.  Maybe it's setting the freeze bit on every page, and
> writing them one page at a time?

That would explain all the writes, but it doesn't seem to explain why
your two servers aren't behaving similarly.

> Still don't understand the call to pollsys, even so, though.

Most likely that's the libc implementation of the select()-based sleeps
for vacuum_cost_delay.  I'm still suspicious that the writes are eating
more cost_delay points than you think.

                        regards, tom lane

-- 
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers

Reply via email to