From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by wx-out-0506.google.com with SMTP id s8so177999wxc for ; Wed, 24 Jan 2007 06:22:43 -0800 (PST) Message-ID: <6d6a94c50701240622n30f1092cq4570f84160fe87f7@mail.gmail.com> Date: Wed, 24 Jan 2007 22:22:43 +0800 From: "Aubrey Li" Subject: Re: [RFC] Limit the size of the pagecache In-Reply-To: <1169625333.4493.16.camel@taijtu> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1169625333.4493.16.camel@taijtu> Sender: owner-linux-mm@kvack.org Return-Path: To: Peter Zijlstra Cc: Christoph Lameter , Vaidyanathan Srinivasan , Nick Piggin , Robin Getz , "Frysinger, Michael" , Bryan Wu , "Hennerich, Michael" , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On 1/24/07, Peter Zijlstra wrote: > On Tue, 2007-01-23 at 16:49 -0800, Christoph Lameter wrote: > > This is a patch using some of Aubrey's work plugging it in what is IMHO > > the right way. Feel free to improve on it. I have gotten repeatedly > > requests to be able to limit the pagecache. With the revised VM statistics > > this is now actually possile. I'd like to know more about possible uses of > > such a feature. > > > > > > > > > > It may be useful to limit the size of the page cache for various reasons > > such as > > > > 1. Insure that anonymous pages that may contain performance > > critical data is never subject to swap. > > This is what we have mlock for, no? > > > 2. Insure rapid turnaround of pages in the cache. > > This sounds like we either need more fadvise hints and/or understand why > the VM doesn't behave properly. > > > 3. Reserve memory for other uses? (Aubrey?) > > He wants to make a nommu system act like a mmu system; this will just > never ever work. Nope. Actually my nommu system works great with some of patches made by us. What let you think this will never work? >Memory fragmentation is a real issue not some gimmick > thought up by the hardware folks to sell these mmu chips. > I totally disagree. Memory fragmentations is the issue not only on nommu, it's also on mmu chips. That's not the reason mmu chips can be sold. -Aubrey -- 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/ . Don't email: email@kvack.org