From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans Reiser Subject: Re: More Slowdown - testscript [noatime,nodiratime] Date: Wed, 23 Nov 2005 20:49:44 -0800 Message-ID: <43854668.8010000@namesys.com> References: <200511171447.41362.mail@earthworm.de> <437CBC63.3050202@namesys.com> <200511172040.39955.mail@earthworm.de> <43820CAD.3090605@namesys.com> <20051121210136.GA25708@favonius> <4383677F.8060106@namesys.com> <3aa654a40511221127x68d059c5hfdfd4254aec0e1b5@mail.gmail.com> <1132709496.7650.24.camel@teratron.lan.etheus.net> <1132710424.7328.7.camel@teratron.lan.etheus.net> <1132777409.7458.8.camel@teratron.lan.etheus.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <1132777409.7458.8.camel@teratron.lan.etheus.net> List-Id: Content-Type: text/plain; charset="us-ascii" To: reiserfs-list@namesys.com Craig Shelley wrote: >With the noatime and nodiratime options, the problem of accessing files >causing a massive sync time has gone. See the results below. > >Although this option has made the system useable, I don't think it has >fully solved the problem. I think fsync() and sync() performance is >still poor, I will do a bit more testing and get back. > >Regards, > > > Sounds like we need to specifically optimize fsync. Well, we have known that for a while, but now it is more true. Ways we can do it include using write twice journaling to a fixed journal area for fsync, and making it possible to specify for a particular file that it should have an atime, and then letting noatime be the default. Probably doing both is best. Atime has been hated by most fs designers for a very very long time, so there might be less resistance to a new standard for this than one would think. Hans