[Forgot to send this to the list first time] On Fri, Oct 31, 2008 at 12:27:27PM -0600, Scott Marlowe wrote: > On Fri, Oct 31, 2008 at 9:36 AM, Chris Butler <chrisb@xxxxxxxxxxx> wrote: > > I've been having intermittent problems with our DB server (running > > postgresql 8.3.3) reaching its connection limit, all because of a SELECT > > statement that's stuck while sending data. This gets stuck because there's a > > transaction waiting to do an ALTER TABLE, then the subsequent SELECTs wait > > for the ALTER. > > > > The problem seems to be that the client connection drops while the server is > > sending data to the client. > Are the clients windows? I know there's a well known and published > bug in windows where it freaks out on blocking ports and the > connection hangs. There's a kb article on it on the ms site. It's > been around since windows 95 or so and there appears to be no plans to > fix it. The client is a PHP webapp running on a Debian VPS. Shortly after sending my previous message, I did spot an error in the client's firewall. It was sending back an ICMP port-unreachable when rejecting TCP packets, rather than a TCP Reset, which I guess is why the connection stayed open rather than closing immediately. Still unsure why it's dropping the connection, but at least it doesn't get stuck any more. -- Chris Butler Zedcore Systems Ltd UK tel: 0114 238 1828 ext 72 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
