From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751451AbWDOUrc (ORCPT ); Sat, 15 Apr 2006 16:47:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751457AbWDOUrc (ORCPT ); Sat, 15 Apr 2006 16:47:32 -0400 Received: from [212.33.180.25] ([212.33.180.25]:27655 "EHLO raad.intranet") by vger.kernel.org with ESMTP id S1751451AbWDOUrb (ORCPT ); Sat, 15 Apr 2006 16:47:31 -0400 From: Al Boldi To: Con Kolivas Subject: Re: [patch][rfc] quell interactive feeding frenzy Date: Sat, 15 Apr 2006 23:45:39 +0300 User-Agent: KMail/1.5 Cc: ck list , linux-kernel@vger.kernel.org, Mike Galbraith References: <200604112100.28725.kernel@kolivas.org> <200604140616.33370.a1426z@gawab.com> <200604151705.18786.kernel@kolivas.org> In-Reply-To: <200604151705.18786.kernel@kolivas.org> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1256" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200604152345.39850.a1426z@gawab.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Con Kolivas wrote: > On Friday 14 April 2006 13:16, Al Boldi wrote: > > Can you try the attached mem-eater passing it the number of kb to be > > eaten. > > > > i.e. '# while :; do ./eatm 9999 ; done' > > > > This will print the number of bytes eaten and the timing in ms. > > > > Assuming timeslice=100, adjust the number of kb to be eaten such that > > the timing will be less than timeslice (something like 60ms). Switch to > > another vt and start another eatm w/ the number of kb yielding more than > > timeslice (something like 140ms). This eatm should starve completely > > after exceeding timeslice. > > > > This problem also exists in mainline, but it is able to break out of it > > to some extent. Setting eatm kb to a timing larger than timeslice does > > not exhibit this problem. > > Thanks for bringing this to my attention. A while back I had different > management of forked tasks and merged it with PF_NONSLEEP. Since then I've > changed the management of NONSLEEP tasks and didn't realise it had > adversely affected the accounting of forking tasks. This patch should > rectify it. Congrats! Much smoother, but I still get this choke w/ 2 eatm 9999 loops running: 9 MB 783 KB eaten in 131 msec (74 MB/s) 9 MB 783 KB eaten in 129 msec (75 MB/s) 9 MB 783 KB eaten in 129 msec (75 MB/s) 9 MB 783 KB eaten in 131 msec (74 MB/s) 9 MB 783 KB eaten in 133 msec (73 MB/s) 9 MB 783 KB eaten in 132 msec (73 MB/s) 9 MB 783 KB eaten in 128 msec (76 MB/s) 9 MB 783 KB eaten in 133 msec (73 MB/s) 9 MB 783 KB eaten in 129 msec (75 MB/s) 9 MB 783 KB eaten in 130 msec (74 MB/s) 9 MB 783 KB eaten in 2416 msec (3 MB/s) <<<<<<<<<<<<< 9 MB 783 KB eaten in 197 msec (48 MB/s) 9 MB 783 KB eaten in 133 msec (73 MB/s) 9 MB 783 KB eaten in 132 msec (73 MB/s) 9 MB 783 KB eaten in 132 msec (73 MB/s) 9 MB 783 KB eaten in 126 msec (77 MB/s) 9 MB 783 KB eaten in 135 msec (72 MB/s) 9 MB 783 KB eaten in 132 msec (73 MB/s) 9 MB 783 KB eaten in 132 msec (73 MB/s) 9 MB 783 KB eaten in 134 msec (72 MB/s) 9 MB 783 KB eaten in 64 msec (152 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 64 msec (152 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 64 msec (152 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) 9 MB 783 KB eaten in 63 msec (154 MB/s) You may have to adjust the kb to get the same effect. Thanks! -- Al