From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id D7EA08D0040 for ; Tue, 22 Mar 2011 16:35:16 -0400 (EDT) Message-ID: <4D8907C2.7010304@fiec.espol.edu.ec> Date: Tue, 22 Mar 2011 15:34:10 -0500 From: =?ISO-8859-1?Q?Alex_Villac=ED=ADs_Lasso?= MIME-Version: 1.0 Subject: Re: [Bugme-new] [Bug 31142] New: Large write to USB stick freezes unrelated tasks for a long time References: <4D839EDB.9080703@fiec.espol.edu.ec> <20110319134628.GG707@csn.ul.ie> <4D84D3F2.4010200@fiec.espol.edu.ec> <20110319235144.GG10696@random.random> <20110321094149.GH707@csn.ul.ie> <20110321134832.GC5719@random.random> <20110321163742.GA24244@csn.ul.ie> <4D878564.6080608@fiec.espol.edu.ec> <20110321201641.GA5698@random.random> <20110322112032.GD24244@csn.ul.ie> <20110322150314.GC5698@random.random> In-Reply-To: <20110322150314.GC5698@random.random> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Arcangeli Cc: Mel Gorman , Andrew Morton , avillaci@ceibo.fiec.espol.edu.ec, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, linux-mm@kvack.org El 22/03/11 10:03, Andrea Arcangeli escribio: > > I asked yesterday by PM to Alex if the mouse pointer moves or not > during the stalls (if it doesn't that may be a scheduler issue with > the compaction irq disabled and lack of cond_resched) and to try > aa.git. Upstream still misses several compaction improvements that we > did over the last weeks and that I've in my queue and that are in -mm > as well. So before making more changes, considering the stack traces > looks very healthy now, I'd wait to be sure the hangs aren't already > solved by any of the other scheduling/irq latency fixes. I guess they > aren't going to help but it worth a try. Verifying if this happens > with a more optimal filesystem like ext4 I think is also interesting, > it may be something in udf internal locking that gets in the way of > compaction. > > If we still have a problem with current aa.git and ext4, then I'd hope > we can find some other more genuine bit to improve like the bits we've > improved so far, but if there's nothing wrong and it gets unfixable, > then my preference would be to either create a defrag mode that is in > between "yes/no", or alternatively to be simpler and make the default > between defrag yes|no configurable at build time and through a command > line in grub, and hope that SLUB doesn't clashes on it too. The > current "default" is optimal for several server environments where we > know most of the allocations are long lived. So we want to still have > an option to be as reliable as we are toady for those. > I have just tested aa.git as of today, with the USB stick formatted as FAT32. I could no longer reproduce the stalls. There was no need to format as ext4. No /proc workarounds required. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org