From: Andreas Dilger Subject: Re: [RFC] Parallelize IO for e2fsck Date: Tue, 22 Jan 2008 00:00:50 -0700 Message-ID: <20080122070050.GM3180@webber.adilger.int> References: <70b6f0bf0801161322k2740a8dch6a0d6e6e112cd2d0@mail.gmail.com> <70b6f0bf0801161330y46ec555m5d4994a1eea7d045@mail.gmail.com> <20080121230041.GL3180@webber.adilger.int> <20080122033830.GR155259@sgi.com> <3673.1200975438@turing-police.cc.vt.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Chinner , Valerie Henson , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Theodore Ts'o , Andreas Dilger , Ric Wheeler To: Valdis.Kletnieks@vt.edu Return-path: In-reply-to: <3673.1200975438@turing-police.cc.vt.edu> Content-disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Jan 21, 2008 23:17 -0500, Valdis.Kletnieks@vt.edu wrote: > On Tue, 22 Jan 2008 14:38:30 +1100, David Chinner said: > > Perhaps instead of swapping immediately, a SIGLOWMEM could be sent > > to a processes that aren't masking the signal followed by a short > > grace period to allow the processes to free up some memory before > > swapping out pages from that process? > > AIX had SIGDANGER some 15 years ago. Admittedly, that was sent when > the system was about to hit OOM, not when it was about to start swapping. I'd tried to advocate SIGDANGER some years ago as well, but none of the kernel maintainers were interested. It definitely makes sense to have some sort of mechanism like this. At the time I first brought it up it was in conjunction with Netscape using too much cache on some system, but it would be just as useful for all kinds of other memory- hungry applications. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.