From: Thavatchai Makphaibulchoke Subject: Re: [PATCH v3 0/2] ext4: increase mbcache scalability Date: Fri, 18 Oct 2013 06:43:18 -0600 Message-ID: <52612CE6.9080609@hp.com> References: <52309F27.8060008@redhat.com> <5230D739.9010109@redhat.com> <20130911212523.GE13397@thunk.org> <5230D450.7000609@hp.com> <20130912122317.GC12918@thunk.org> <5232FF3E.7080604@hp.com> <5233609F.7060303@redhat.com> <523886CE.2070203@hp.com> <5239B65E.4060202@redhat.com> <20130921185304.GB8606@thunk.org> <52432EB5.1090706@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Theodore Ts'o , Eric Sandeen , "linux-ext4@vger.kernel.org List" , "Chandramouleeswaran, Aswin" , Linus Torvalds To: Andreas Dilger Return-path: Received: from g1t0028.austin.hp.com ([15.216.28.35]:30832 "EHLO g1t0028.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756800Ab3JRSrn (ORCPT ); Fri, 18 Oct 2013 14:47:43 -0400 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On 10/03/2013 09:22 PM, Andreas Dilger wrote: > > This is a pretty significant price to pay for SELinux in any case. > I guess it is probably lower overhead with 256-byte inodes, but > anything that adds 5-25% overhead shouldn't be taken for granted. > > Cheers, Andreas > So far we have determined that, - With SELinux enabled a ramdisk filesytem, with default node size of 128 bytes, extended xattr is generated - In one of the aim7 workload, mbcache has a hit ratio of about 65% Seems like mbcache itself and the mbcache lock optimization attempt by the patch could actually improve performance for a real word system where extended xattr is employed. I believe the patch should go in if there isn't any concern. Please let me know if there is any comment or concern about the patch. Thanks, Mak.