Memory use flares up sharply, how to troubleshoot?

[Maxim Dounin]

Hello!

On Mon, Jul 21, 2014 at 02:18:08PM -0400, gthb wrote:

[...]

> > The debuging log includes full information about all memory
> > allocations, see http://nginx.org/en/docs/debugging_log.html.
> 
> Thank you. I haven't been able to reproduce this outside of production (or
> even in production) so I might have to leave debug logging enabled in
> production and hope to catch this next time it happens. Am I right to assume
> that enabling debug is going to weigh quite heavily on production usage, and
> eat up disk very fast? (Traffic peaks at around 100 req/sec and 2 MB/sec.)

While debug logging is costly enough to notice, 100 r/s is quite 
low and it should be fine to just enable the logging.  If in 
doubt, you may start with enabling debug only for a fraction of 
users using the debug_connection directive, see 
http://nginx.org/r/debug_connection.

In any case, it may be a good idea to show full configuration as 
recommended at http://wiki.nginx.org/Debugging#Asking_for_help - 
mostly to make sure you haven't overlooked something obvious like 
"uwsgi_buffer_size 10m" or alike.

-- 
Maxim Dounin
http://nginx.org/