From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 4 Aug 2007 21:42:59 +0200 From: =?utf-8?B?SsO2cm4=?= Engel Subject: Re: [PATCH 00/23] per device dirty throttling -v8 Message-ID: <20070804194259.GA25753@lazybastard.org> References: <20070804063217.GA25069@elte.hu> <20070804070737.GA940@elte.hu> <20070804103347.GA1956@elte.hu> <20070804163733.GA31001@elte.hu> <46B4C0A8.1000902@garzik.org> <20070804191205.GA24723@lazybastard.org> <20070804192130.GA25346@elte.hu> <20070804192615.GA25600@lazybastard.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20070804192615.GA25600@lazybastard.org> Sender: owner-linux-mm@kvack.org Return-Path: To: =?utf-8?B?SsO2cm4=?= Engel Cc: Ingo Molnar , 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: On Sat, 4 August 2007 21:26:15 +0200, JA?rn Engel wrote: > > Given the choice between only "atime" and "noatime" I'd agree with you. > Heck, I use it myself. But "relatime" seems to combine the best of both > worlds. It currently just suffers from mount not supporting it in any > relevant distro. And here is a completely untested patch to enable it by default. Ingo, can you see how good this fares compared to "atime" and "noatime,nodiratime"? JA?rn -- Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian W. Kernighan --- linux-2.6.22_relatime/fs/namespace.c~default_relatime 2007-05-16 02:01:39.000000000 +0200 +++ linux-2.6.22_relatime/fs/namespace.c 2007-08-04 21:36:20.000000000 +0200 @@ -1401,6 +1401,10 @@ long do_mount(char *dev_name, char *dir_ if (data_page) ((char *)data_page)[PAGE_SIZE - 1] = 0; +#ifdef CONFIG_DEFAULT_RELATIME + flags |= MS_RELATIME; +#endif + /* Separate the per-mountpoint flags */ if (flags & MS_NOSUID) mnt_flags |= MNT_NOSUID; --- linux-2.6.22_relatime/fs/Kconfig~default_relatime 2007-05-16 02:01:38.000000000 +0200 +++ linux-2.6.22_relatime/fs/Kconfig 2007-08-04 21:39:46.000000000 +0200 @@ -6,6 +6,15 @@ menu "File systems" if BLOCK +config DEFAULT_RELATIME + bool "Mount all filesystems with 'relatime' by default" + default y + help + Relatime only updates atime once after any file has been changed. + Setting this should give a noticeable performance bonus. + + If unsure, say Y. + config EXT2_FS tristate "Second extended fs support" help -- 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