Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265093AbUD3Hwu (ORCPT ); Fri, 30 Apr 2004 03:52:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265102AbUD3Hwu (ORCPT ); Fri, 30 Apr 2004 03:52:50 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:20414 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S265093AbUD3Hwr (ORCPT ); Fri, 30 Apr 2004 03:52:47 -0400 Message-ID: <409205C1.7000700@pobox.com> Date: Fri, 30 Apr 2004 03:52:33 -0400 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andrew Morton CC: Andy Isaacson , pj@sgi.com, vonbrand@inf.utfsm.cl, nickpiggin@yahoo.com.au, brettspamacct@fastclick.com, linux-kernel@vger.kernel.org Subject: Re: ~500 megs cached yet 2.6.5 goes into swap hell References: <40904A84.2030307@yahoo.com.au> <200404292001.i3TK1BYe005147@eeyore.valparaiso.cl> <20040429133613.791f9f9b.pj@sgi.com> <20040429141947.1ff81104.akpm@osdl.org> <20040429143403.35a7a550.pj@sgi.com> <20040429145725.267ea7b8.akpm@osdl.org> <20040430000408.GA29096@hexapodia.org> <20040429173223.3ea4d0c5.akpm@osdl.org> In-Reply-To: <20040429173223.3ea4d0c5.akpm@osdl.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1078 Lines: 31 Andrew Morton wrote: > Andy Isaacson wrote: > >> But in a related case, I have a background daemon that does a lot of IO >> (mostly sequential, one page at a time read/modify/write of a multi-GB >> file) to a filesystem on a separate spindle from my main filesystems. >> I'd like to use a similar mechanism to say "don't let this program eat >> my pagecache" that will let the daemon crunch away without severely >> impacting my desktop work. > > > fadvise(POSIX_FADV_DONTNEED) is ideal for this. Run it once per megabyte > or so. Sweet. I'm so happy you added posix_fadvise (way back when), and even happier to hear this. Does our fadvise support len==0 ("I mean the whole file")? That's defined in POSIX, and would allow a compliant app to simply POSIX_FADV_DONTNEED once at the beginning. Jeff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/