From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 99C6A6B00D0 for ; Thu, 5 Mar 2009 09:43:27 -0500 (EST) From: Markus Subject: Re: drop_caches ... Date: Thu, 5 Mar 2009 15:43:22 +0100 References: <200903041057.34072.M4rkusXXL@web.de> <200903051505.26584.M4rkusXXL@web.de> <20090305142230.GA23465@localhost> In-Reply-To: <20090305142230.GA23465@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200903051543.22516.M4rkusXXL@web.de> Sender: owner-linux-mm@kvack.org To: linux-kernel@vger.kernel.org Cc: Wu Fengguang , Zdenek Kabelac , "linux-mm@kvack.org" , Lukas Hejtmanek List-ID: > > > Could you please try the attached patch which will also show the > > > user and process that opened these files? It adds three more fields > > > when CONFIG_PROC_FILECACHE_EXTRAS is selected. > > > > > > Thanks, > > > Fengguang > > > > > > On Thu, Mar 05, 2009 at 01:55:35PM +0200, Markus wrote: > > > > > > > > # sort -n -k 3 filecache-2009-03-05 | tail -n 5 > > > > 15886 7112 7112 100 1 d- 00:08 > > > > (tmpfs) /dev/zero\040(deleted) > > > > 16209 35708 35708 100 1 d- 00:08 > > > > (tmpfs) /dev/zero\040(deleted) > > > > 16212 82128 82128 100 1 d- 00:08 > > > > (tmpfs) /dev/zero\040(deleted) > > > > 15887 340024 340024 100 1 d- 00:08 > > > > (tmpfs) /dev/zero\040(deleted) > > > > 15884 455008 455008 100 1 d- 00:08 > > > > (tmpfs) /dev/zero\040(deleted) > > > > > > > > The sum of the third column is 1013 MB. > > > > To note the biggest ones (or do you want the whole file?)... and > > thats > > > > after a sync and a drop_caches! (Can be seen in the commands given.) > > > > I could, but I know where these things belong to. Its from sphinx (a > > mysql indexer) searchd. It loads parts of the index into memory. > > The sizes looked well-known and killing the searchd will reduce "cached" > > to a normal amount ;) > > And it's weird about the file name: /dev/zero. I wonder how it > managed to create that file, and then delete it, inside a tmpfs! I dont know exactly. But in the source its just a: ... mmap ( NULL, m_iLength, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0 ); Perhaps thats the way shared anonymous memory is handled?! > Just out of curiosity, are they shm objects? Can you show us the > output of 'df'? In your convenient time. Thats all: # df -h Filesystem Size Used Avail Use% Mounted on /dev/md6 14G 7.9G 5.9G 58% / udev 10M 304K 9.8M 3% /dev cachedir 4.0M 100K 4.0M 3% /lib64/splash/cache /dev/md4 19G 15G 3.2G 82% /home /dev/md3 8.3G 4.5G 3.8G 55% /usr/portage shm 2.0G 0 2.0G 0% /dev/shm > > I just dont know why its in "cached" (can that be swapped out btw?). > > But I think thats not a problem of the kernel, but of anonymous > > mmap-ing. > > You know, because the file is created in tmpfs, which is swap-backed. > By definition the pages here cannot be dropped by third-party. Hm, ok. > > I think its resolved, thanks to everybody and Fengguang in particular! > > You are welcome :-) ;) Have a nice day. Markus -- 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