Re: First steps with 8.3 and autovacuum launcher - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: First steps with 8.3 and autovacuum launcher
Date
Msg-id 20071001225655.GA9430@alvh.no-ip.org
Whole thread Raw
In response to Re: First steps with 8.3 and autovacuum launcher  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: First steps with 8.3 and autovacuum launcher
List pgsql-hackers
Tom Lane escribió:
> Simon Riggs <simon@2ndquadrant.com> writes:
> > We should not allow VACUUM to be concurrent with either CREATE INDEX or
> > ANALYZE, but then thats not the problem here anyway.
> 
> I can't believe anyone is short-sighted enough to think that.
> 
> The problem here is that autovac takes locks that block foreground
> sessions that want exclusive locks.  We've always known this and always
> ignored it, but if autovac is on by default then it's going to be in
> people's faces a lot more than it was before, and they won't be happy.
> 
> If you insist on crafting a solution that only fixes this problem for
> pg_restore's narrow usage, you'll be back revisiting it before beta1
> has been out a month.

So you say we should make any job that needs an exclusive lock on a
table to be able to cancel a running autovac job?  If we did that,
autovac couldn't do very much of anything.

If that's not what you're saying, I'm afraid I'm not getting it.

-- 
Alvaro Herrera                  http://www.amazon.com/gp/registry/5ZYLFMCVHXC
Maybe there's lots of data loss but the records of data loss are also lost.
(Lincoln Yeoh)


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