On 10/07/2011 01:21 AM, Sean Laurent wrote:
> Within a few seconds of the backup, our application servers start
> throwing exceptions that indicate the database connection was closed.
> Meanwhile, Postgres still shows the connections and we start seeing a
> really high number (for us) of locks in the database. The application
> servers refuse to recover and must be killed and restarted. Once they're
> killed off, the connections actually go away and the locks disappear.
Did you have any luck with this?
This sort of thing sounds a lot like "deadlock" ... but I'm not really
sure how Pg's backends/postmaster could get into a deadlock with each
other. It'd be interesting to look at "wchan" in ps to see what the Pg
processes are waiting on.
Also, check to see if you can connect with `psql' on a local unix socket
and on a local tcp/ip socket.
Can you reproduce this on a non-EC2 system?
--
Craig Ringer