[Server-devel] Ejabberd CPU/RAM Spike -> Crashes

[Martin Langhoff]

On Mon, Dec 21, 2009 at 3:14 PM, Martin Langhoff
<martin.langhoff at gmail.com> wrote:
> Now it's up on a pristine state, and I am monitoring it...

Ok - the problem seems related to Moodle's control of ejabberd
presence service. The sync between Moodle and ejabberd data (in
mnesia) was taking too long, and a second Moodle sync process would
start... and then a 3rd... and then...

This led to errors that should be benign (an error reported in the
logs, but not  leading to a functional problem) -- because ejabberd's
internals are all about supporting things that happen concurrently.
But! something inside ejabberd isn't liking the concurrency.

I've added a big lock around the process, so from now on Moodle
processes won't overlap in this sync. This means that your server is
now running a lightly patched Moodle -- I will release this as a new
rpm soon.

According to ps_mem.py, beam started at 14MB and now grown to 16MB,
this is with no users connected. In normal operation (once users
connect), I would expect it to grow to ~40MB.

cheers,


m
-- 
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 martin at laptop.org -- School Server Architect
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