Out of memory issues caused by error_logger

[Suhail Doshi]

I am pretty sure I am having this issue:
http://blogtrader.net/blog/a_case_study_of_scalable

Though he talks about it, he doesn't offer a solution--does anyone
know a good solution. I am noticing my mochiweb process hits 4G of
used memory every now and then (we do a sizable amount of requests a
second). The server essentially becomes unresponsive. Debugging in the
past showed it was error_logger proc.

[Anton Krasovsky]

Are you logging anything to error_logger or the logging messages are
the byproduct of crashes? I had the later problem, where processes
handling large binaries (images) would crash and erorr logger would
use too much memory trying to pretty-print the crashed process data.

anton

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[Bob Ippolito]

You can get around that by handling exceptions in your loop function
and providing your own error logging (or not). The pattern we use
looks basically like this:

loop(Req) ->
try
%% do something here
catch
exit:normal ->
%% this happens when the client closed the connection
exit(normal);
Type:What ->
Report = ["web request failed",
{path, Req:get(path)},
{type, Type}, {what, What},
{trace, erlang:get_stacktrace()}],
error_logger:error_report(Report),
Req:respond({500, [], []})
end.

[Anton Krasovsky]

Thanks Bob! I've stopped handling large binaries in-process, but that snipet
would come handy to silence the occasional unexpected requests, like
proxy scanning attempts, etc.

Anton