Re: BUG #9635: Wal sender process is using 100% CPU

On 03/19/2014 07:13 PM, jkoceniak@mediamath.com wrote:
> The following bug has been logged on the website:
>
> Bug reference:      9635
> Logged by:          Jamie Koceniak
> Email address:      jkoceniak@mediamath.com
> PostgreSQL version: 9.1.9
> Operating system:   x86_64-unknown-linux-gnu (Debian 4.7.2-5) 64-bit
> Description:
>
> Periodically throughout the day, we keep seeing the wal sender process
> utilize 100% of the CPU. We began noticing this after we added 2 new slave
> servers, going from 2 to 4 slaves. See top results and I also included our
> wal settings. Thanks!

Hmm. There was a bug that caused walsender to go into a busy-loop, when
the standby disconnected. But that was fixed in 9.1.4 already.

Could you attach to one of the processes with gdb and see what functions
are being called? Or strace, or "perf top" or something.

- Heikki