From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx112.postini.com [74.125.245.112]) by kanga.kvack.org (Postfix) with SMTP id 04BAA6B0002 for ; Mon, 22 Apr 2013 08:19:11 -0400 (EDT) Received: by mail-we0-f172.google.com with SMTP id r3so6269675wey.17 for ; Mon, 22 Apr 2013 05:19:10 -0700 (PDT) Subject: Re: page eviction from the buddy cache Mime-Version: 1.0 (Apple Message framework v1283) Content-Type: text/plain; charset=us-ascii From: Alexey Lyahkov In-Reply-To: <51730619.3030204@fastmail.fm> Date: Mon, 22 Apr 2013 15:18:59 +0300 Content-Transfer-Encoding: quoted-printable Message-Id: <51874517-8D82-433E-9E10-13167C736D5F@gmail.com> References: <51504A40.6020604@ya.ru> <20130327150743.GC14900@thunk.org> <3C8EEEF8-C1EB-4E3D-8DE6-198AB1BEA8C0@gmail.com> <515CD665.9000300@gmail.com> <239AD30A-2A31-4346-A4C7-8A6EB8247990@gmail.com> <51730619.3030204@fastmail.fm> Sender: owner-linux-mm@kvack.org List-ID: To: Bernd Schubert Cc: Will Huck , Hugh Dickins , Theodore Ts'o , Andrew Perepechko , linux-ext4@vger.kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org Bernd, I fact marking REQ_META will help with io scheduler(). I and Andrew will discuss it's some time ago, but don't expect a too = much performance improvements anyway - i will pickup patch from Intel jira and ask performance = engineer to evaluate it.=20 bw. My problem is in memory caching.=20 I may rewrite a buddy cache to avoid using a page cache at all as these = pages but LRU aging will lost. On Apr 21, 2013, at 00:18, Bernd Schubert wrote: > Alex, Andrew, >=20 > did you notice the patch Ted just sent? > ("ext4: mark all metadata I/O with REQ_META") >=20 > I would like to see a way to mark pages read in with REQ_META to be = kept > in cache preferred over other pages. I guess that would solve LU-15 > (https://jira.hpdd.intel.com/browse/LU-15) and also the direntry-block > issue I tried to solve about 2 years ago > (http://patchwork.ozlabs.org/patch/101200/). But using REQ_META to tag > pages would probably also solve the same issue for other file systems. > Is there anything already in the mm layer that could be used for that? >=20 > Thanks, > Bernd >=20 -- 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