From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 8 May 2001 21:21:16 +0200 From: Jens Axboe Subject: Re: [PATCH] allocation looping + kswapd CPU cycles Message-ID: <20010508212116.N505@suse.de> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ; from marcelo@conectiva.com.br on Tue, May 08, 2001 at 02:23:56PM -0300 Sender: owner-linux-mm@kvack.org Return-Path: To: Marcelo Tosatti Cc: Mark Hemment , Linus Torvalds , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Tue, May 08 2001, Marcelo Tosatti wrote: > > The attached patch (against 2.4.5-pre1) fixes the looping symptom, by > > adding a counter and looping only twice for non-zero order allocations. > > Looks good. (actually Rik had a patch similar to this which fixed a real > case with cdda2wav just like you described) Not cdda2wav, I pressume, but the optimization discussed here before that wasn't really doable because of the vm behaviour when doing do try to alloc some amount of contiogous pages if (ok) break lower number of pages wanted while true CDROMREADAUDIO stopped doing this and fell back to single cdda frame size allocations because of these failures, even though it meant a huge decrease in speed. cdda2wav will ask for iirc 16 frames at the time, the current driver will try and to 8 first and then fall back to slower extraction if allocations fail. -- Jens Axboe -- 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.eu.org/Linux-MM/