From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 6 Aug 2007 08:58:34 +0200 From: Ingo Molnar Subject: Re: [PATCH 00/23] per device dirty throttling -v8 Message-ID: <20070806065834.GB2818@elte.hu> References: <20070804163733.GA31001@elte.hu> <46B4C0A8.1000902@garzik.org> <20070804191205.GA24723@lazybastard.org> <20070804192130.GA25346@elte.hu> <20070804211156.5f600d80@the-village.bc.nu> <20070804202830.GA4538@elte.hu> <20070804224834.5187f9b7@the-village.bc.nu> <20070805071320.GC515@elte.hu> <20070805152231.aba9428a.diegocg@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070805152231.aba9428a.diegocg@gmail.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Diego Calleja Cc: Alan Cox , J??rn Engel , Jeff Garzik , Linus Torvalds , Peter Zijlstra , linux-mm@kvack.org, Linux Kernel Mailing List , miklos@szeredi.hu, akpm@linux-foundation.org, neilb@suse.de, dgc@sgi.com, tomoki.sekiyama.qu@hitachi.com, nikita@clusterfs.com, trond.myklebust@fys.uio.no, yingchao.zhou@gmail.com, richard@rsk.demon.co.uk, david@lang.hm List-ID: * Diego Calleja wrote: > > Measurements show that noatime helps 20-30% on regular desktop > > workloads, easily 50% for kernel builds and much more than that (in > > excess of 100%) for file-read-intense workloads. We cannot just walk > > And as everybody knows in servers is a popular practice to disable it. > According to an interview to the kernel.org admins.... yeah - but i'd be surprised if more than 1% of all Linux servers out there had noatime. > "Beyond that, Peter noted, "very little fancy is going on, and that is > good because fancy is hard to maintain." He explained that the only > fancy thing being done is that all filesystems are mounted noatime > meaning that the system doesn't have to make writes to the filesystem > for files which are simply being read, "that cut the load average in > half." nice quote :-) > I bet that some people would consider such performance hit a bug... yeah. Ingo -- 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