On Thu, 2009-10-15 at 19:58 -0400, Tom Lane wrote: > Alvaro Herrera <alvhe...@commandprompt.com> writes: > > Hmm ... this is something that had not occured to me earlier. There is > > a connection pool here (JDBCConnectionPool I'm told; hadn't heard about > > that one) and there are about 100 backends permanently, not all of which > > are always busy. Perhaps what's going on here is that some of them are > > idle for long enough that the sinval queue gets full. > > Hm, that's definitely possible, and 8.1 did not have very good code for > coping with sinval overrun. But it's not clear to me why that would > affect the rel extension code path in particular.
I don't think this is an issue that affects the rel extension path alone. The typical behaviour is to attempt to assign work, if connection busy then start a new connection and do work there. If the type of work being done is similar then this behaviour means that contention leads to additional contention. So *any* form of contention gets magnified. -- Simon Riggs www.2ndQuadrant.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
