From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id BAA27265; Sat, 10 Jul 2004 01:22:22 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id BAA24412 for ; Sat, 10 Jul 2004 01:22:21 +0200 (MET DST) Received: from mproxy.gmail.com (rproxy.gmail.com [64.233.170.207]) by nez-perce.inria.fr (8.12.10/8.12.10) with SMTP id i69NMJEV031982 for ; Sat, 10 Jul 2004 01:22:20 +0200 Received: by mproxy.gmail.com with SMTP id d78so98686rnf for ; Fri, 09 Jul 2004 16:21:52 -0700 (PDT) Received: by 10.38.206.72 with SMTP id d72mr170296rng; Fri, 09 Jul 2004 16:21:52 -0700 (PDT) Message-ID: Date: Fri, 9 Jul 2004 16:21:52 -0700 From: Donald Wakefield To: caml-list Subject: Re: [Caml-list] Thread and kernel 2.6 pb still there in CVS In-Reply-To: <20040628150805.GC7353@yquem.inria.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit References: <20040624194603.2A91010EF06@clark.cs.brown.edu> <1088158825.1941.113.camel@pelican.wigram> <20040625110748.GB2707@bourg.inria.fr> <1088166608.1941.120.camel@pelican.wigram> <40DC38D3.4010009@univ-savoie.fr> <20040628150805.GC7353@yquem.inria.fr> X-Miltered: at nez-perce with ID 40EF28AB.001 by Joe's j-chkmail (http://j-chkmail.ensmp.fr)! X-Loop: caml-list@inria.fr X-Spam: no; 0.00; wakefield:99 wakefield:99 caml-list:01 2004:99 kernels:01 sched:01 bug:01 kernels:01 sched:01 posix:01 quantum:99 bug:01 cid:99 kernel:01 kernel:01 Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk On Mon, 28 Jun 2004 17:08:05 +0200, Xavier Leroy wrote: > > The 2.6 Linux kernels changed the behavior of sched_yield() in a way > that causes the unfairness you observed. Other threaded applications > are affected, including Open Office (!). My belief is that it's > really a bug in 2.6 kernels and that the new behavior of sched_yield(), > while technically conformant to the POSIX specs, lowers the quality of > implementation quite a lot. > > (I seem to remember from my LinuxThreads development days that this > isn't the first time the kernel developers broke sched_yield(), then > realized their error.) I know this comes a bit late in this 'thread', but there's been discussion on Slashdot on a new scheduler framework called Bossa. I posted a quote from Xavier's discussion of sched_yield, and another poster replied. In brief: "...OpenOffice.org and Ocaml have to wait too long for their next CPU quantum, but that's because they are CPU bound tasks and it's their own fault. "The bug was in past versions of Linux where, although it was pre-emptive, sched_yield was allowed some power - it should have been ignored in user-space and the scheduler decided what gets CPU and when. Depending on that bug is also a bug and the mis-users deserve everything they get." The full reply can be read at: -- Don Wakefield don.wakefield@gmail.com ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners