From: Eric Wong <normalperson@yhbt.net>
To: unicorn list <mongrel-unicorn@rubyforge.org>
Subject: Re: A barrage of unexplained timeouts
Date: Thu, 22 Aug 2013 04:09:03 +0000 [thread overview]
Message-ID: <20130822040903.GA14870@dcvr.yhbt.net> (raw)
In-Reply-To: <A48E934780B64D9BB79B265E95F84302@gmail.com>
Jimmy Soho <jimmy.soho@gmail.com> wrote:
> fwiw, we experience this too irregularly, about once a week or 2 weeks
> for a few seconds, and sometimes up to a minute or 2 minutes long. for
> no apparent reasons indeed. and at random times.
Wait, based on what you say below, is this happening to unicorn or
nginx?
> my suspicion so far has always been that this is due to bad (wifi)
> networks of clients. what happens when a request is handled
> successfully by rails, but for whatever reason the last bit of the
> response can't be delivered because the receiving end is not consuming
> in a timely fashion?
So nginx is complaining about disconnected clients, not unicorn,
correct?
> If i'm not mistaken i think that rails logs a 200 success message
> before the response is actually send back?
Correct, rails/unicorn won't know if the client disconnected until
nginx breaks the connection to unicorn.
> Is a response send back by rails / unicorn fully buffered by nginx? Or
> is a unicorn worker blocked until the response is confirmed to have
> been successfully received by the client?
nginx fully buffers both requests and responses by default.
Which leads us to...
> Aside: how do you protect your unicorn workers against a barrage of
> client requests that eat the response veeeeeery sloooooooowly?
That's the whole point of using nginx with unicorn. nginx shields
unicorn from slow clients.
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next prev parent reply other threads:[~2013-08-22 4:09 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-20 14:47 A barrage of unexplained timeouts nick
2013-08-20 16:37 ` Eric Wong
2013-08-20 17:27 ` nick
2013-08-20 17:40 ` Eric Wong
2013-08-20 18:11 ` nick
2013-08-20 18:49 ` Eric Wong
2013-08-20 20:03 ` nick
2013-08-20 20:42 ` Eric Wong
2013-08-20 21:19 ` nick
2013-08-20 21:32 ` Eric Wong
2013-08-21 13:33 ` nick
2013-08-22 2:32 ` Jimmy Soho
2013-08-22 4:09 ` Eric Wong [this message]
2013-08-22 13:10 ` nick
2013-08-22 17:05 ` Eric Wong
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