Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965551AbXAYGfb (ORCPT ); Thu, 25 Jan 2007 01:35:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965546AbXAYGfa (ORCPT ); Thu, 25 Jan 2007 01:35:30 -0500 Received: from wx-out-0506.google.com ([66.249.82.232]:3902 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965551AbXAYGfa (ORCPT ); Thu, 25 Jan 2007 01:35:30 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=D1CWP+DCNC2CFkmVJT+tNldbvwYuJYjkojQE6CCvQi1ktQ8ntCf/4myof+X7nh8q6rlVKy1HW41PlKTsxMBqhadyHZ7hTq28c5F4ICJgPx2US2kOOEPRDYBJnVNjWBzqpPYQwp2F8jc1U6SI9knFRscAND3MHYs7v5jBHe0/VQw= Message-ID: <6d6a94c50701242235m48013856kb5a947c489d9da37@mail.gmail.com> Date: Thu, 25 Jan 2007 14:35:29 +0800 From: "Aubrey Li" To: "Vaidyanathan Srinivasan" Subject: Re: [RFC] Limit the size of the pagecache Cc: "Christoph Lameter" , "Nick Piggin" , "Robin Getz" , "Hennerich, Michael" , linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <45B82F41.9040705@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <45B75208.90208@linux.vnet.ibm.com> <45B82F41.9040705@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1518 Lines: 35 On 1/25/07, Vaidyanathan Srinivasan wrote: > > > Christoph Lameter wrote: > > On Wed, 24 Jan 2007, Vaidyanathan Srinivasan wrote: > > > >> With your patch, MMAP of a file that will cross the pagecache limit hangs the > >> system. As I mentioned in my previous mail, without subtracting the > >> NR_FILE_MAPPED, the reclaim will infinitely try and fail. > > > > Well mapped pages are still pagecache pages. > > > > Yes, but they can be classified under a process RSS pages. Whether it > is an anon page or shared mem or mmap of pagecache, it would show up > under RSS. Those pages can be limited by RSS limiter similar to the > one we are discussing in pagecache limiter. In my opinion, once a > file page is mapped by the process, then it should be treated at par > with anon pages. Application programs generally do not mmap a file > page if the reuse for the content is very low. > I agree, we shouldn't take mmapped page into account. But Vaidy - even with your patch, we are still using the existing reclaimer, that means we dont ensure that only page cache is reclaimed/limited. mapped pages will be hit also. I think we still need to add a new scancontrol field to lock mmaped pages and remove unmapped pagecache pages only. -Aubrey - 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/