On Tuesday 11 February 2014 16:44:57 Aleksandar Lazic wrote: > > Am 11-02-2014 16:28, schrieb Valentin V. Bartenev: > > On Tuesday 11 February 2014 19:06:37 Maxim Dounin wrote: > >> Hello! > >> > >> On Tue, Feb 11, 2014 at 06:16:48PM +0400, Valentin V. Bartenev wrote: > >> > >> > On Tuesday 11 February 2014 18:06:38 Maxim Dounin wrote: > >> > [..] > >> > > > >(As for backlog size, I usually set it to something big enough to > >> > > > >accomodate about 1 or 2 seconds of expected peek connection rate. > >> > > > >That is, 1024 is good enough for about 500 connections per second. > >> > > > >But with deferred on Linux, it looks like deferred connection are > >> > > > >sitting in the same queue as normal ones, and this may drastically > >> > > > >change things.) > >> > > > > >> > > > OK. That means with deferred I should double or divide the > >> > > > listening value? > >> > > > >> > > With deferred, it looks like all (potential) deferred connection > >> > > should be added to the value. And it's very hard to tell how many > >> > > there will be. > >> > > > >> > > >> > Deferred connections stay in syn backlog which controlled > >> > by tcp_max_syn_backlog. > >> > >> You mean they aren't counted to listen socket's backlog, right? > > > > Yes. > > > >> Is there any way to see how many such connections are queued then? > > > > They all stay in SYN_RECV state. If I understand right, something > > like this will show: > > > > # netstat -n | grep SYN_RECV | grep :80 | wc -l > > We have a average from ~200 here. > > Is this good/bad/not worth ? >
Not a problem at all, till it's noticeable lower than tcp_max_syn_backlog. wbr, Valentin V. Bartenev _______________________________________________ nginx mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx
