On Thu, Feb 12, 2015 at 4:33 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Dave Johansen <davejohansen@gmail.com> writes: > I'm running Postgres 8.4.20 on RHEL 6.4 and it will occasionally crash. The > postgres.log file just says that a PID was terminated. The output from > dmesg has a message like this one: > postmaster[22905]: segfault at 686 ip 0000000000000686 sp 00007fff83d72e88 > error 14 in postgres[400000+463000]
> What can I do to try and figure out what is causing the crash and fix it?
(1) install relevant postgresql-debuginfo package (assuming we're talking about a Red Hat-originated postgres package)
(2) run postmaster under "ulimit -c unlimited" (easiest way is probably to add such a command to /etc/rc.d/init.d/postgresql and restart the service)
(3) wait for crash
(4) gdb the resulting corefile (should be under your $PGDATA directory)
(5) send in a stack trace.
Thanks for the info. It will take a little while for me to get this all approved and setup, but should be helpful info.
Also, could this be caused by an issue or misuse of libpq/libpqxx in our application? If so, is there someway that we could turn on some sort of logging logging to see the queries or at least connections that we opening when or just before the crash happened?
Keep in mind that 8.4.x is out of support so far as the PG community is concerned, so we're unlikely to expend any great amount of effort on this; but we can take a quick look at a stack trace to see if it looks like a known problem.
Yes, we're in the process of working on upgrading to 9.2, but it will probably still be a while. If we are able to track down some issue, then we'd bring it up to RedHat and request that they resolve it.