From: Eric Wong <e@yhbt.net> To: Stan Hu <stanhu@gmail.com> Cc: unicorn-public@yhbt.net Subject: Re: Sustained queuing on one listener can block requests from other listeners Date: Thu, 16 Apr 2020 06:59:17 +0000 [thread overview] Message-ID: <20200416065917.GA7256@dcvr> (raw) In-Reply-To: <CAMBWrQmzXYjDobExF9GL1BkHAc=ibvMv1ciaSv_fLQ36MyZW0g@mail.gmail.com> Stan Hu <stanhu@gmail.com> wrote: > Thanks, Eric. That patch didn't work; it spun the CPU. I think this worked? Oops, sorry. I was too eager to drop `nr += 1' :x Btw, please don't top post. Fwiw, I wouldn't mind if we stopped quoting at all on publically-archived lists (saves space and bandwidth). > +++ b/lib/unicorn/http_server.rb > @@ -708,7 +708,7 @@ def worker_loop(worker) > # we're probably reasonably busy, so avoid calling select() > # and do a speculative non-blocking accept() on ready listeners > # before we sleep again in select(). > - unless nr == 0 > + if nr == readers.size > tmp = ready.dup > redo > end Your patch looks close. However the `readers' array gets dropped on SIGQUIT with `nuke_listeners!', so `readers.size' is unstable. How about this? diff --git a/lib/unicorn/http_server.rb b/lib/unicorn/http_server.rb index a52931a..45a2e97 100644 --- a/lib/unicorn/http_server.rb +++ b/lib/unicorn/http_server.rb @@ -686,6 +686,7 @@ def worker_loop(worker) trap(:USR1) { nr = -65536 } ready = readers.dup + nr_listeners = readers.size @after_worker_ready.call(self, worker) begin @@ -708,7 +709,7 @@ def worker_loop(worker) # we're probably reasonably busy, so avoid calling select() # and do a speculative non-blocking accept() on ready listeners # before we sleep again in select(). - unless nr == 0 + if nr == nr_listeners tmp = ready.dup redo end Thanks
next prev parent reply other threads:[~2020-04-16 6:59 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-04-15 5:06 Stan Hu 2020-04-15 5:26 ` Eric Wong 2020-04-16 5:46 ` Stan Hu 2020-04-16 6:59 ` Eric Wong [this message] 2020-04-16 7:24 ` Stan Hu 2020-04-16 9:24 ` [PATCH] prevent single listener from monopolizing a worker Eric Wong
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