From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Wong Subject: Re: epoll with ONESHOT possibly fails to deliver events Date: Sat, 22 Dec 2012 02:54:14 +0000 Message-ID: <20121222025414.GA6217@dcvr.yhbt.net> References: <20121213093242.GA25436@dcvr.yhbt.net> <2F8919C4-395F-4029-8D4F-AD16A3815FC5@yale.edu> <9BE5F9A7-4D5B-4848-A0BA-55004240B6E0@yale.edu> <20121220213210.GA22655@dcvr.yhbt.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Voellmy , viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: "Junchang(Jason) Wang" Return-path: Received: from dcvr.yhbt.net ([64.71.152.64]:57712 "EHLO dcvr.yhbt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135Ab2LVCyP (ORCPT ); Fri, 21 Dec 2012 21:54:15 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org List-ID: "Junchang(Jason) Wang" wrote: > We still believe this is a bug in epoll system even though we can't > prove that so far. Both Andi and I are very interested in this problem > and helping you experts solve this it. Just let us know if we can > help. I'm just another epoll user, definitely not an expert. Hopefully somebody else can figure this out, because I'm unable to reproduce the problem with your code and I haven't spotted any bugs from reading through the kernel. Curious, I also have a multi-threaded HTTP server which is a little similar (multi-threaded, 2 epoll descriptors (only one epoll is heavily used). I run it on 2/4-core systems and haven't hit issues with epoll. If you want to test, it should be easy to build from tarball: http://bogomips.org/cmogstored/files/cmogstored-1.0.0.tar.gz configure && make ./cmogstored --httplisten=8080 --docroot=/path/to/whatever More info here: http://bogomips.org/cmogstored/README git clone http://bogomips.org/cmogstored.git