Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754412AbZCDOKA (ORCPT ); Wed, 4 Mar 2009 09:10:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751427AbZCDOJu (ORCPT ); Wed, 4 Mar 2009 09:09:50 -0500 Received: from mx2.redhat.com ([66.187.237.31]:46392 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751269AbZCDOJu (ORCPT ); Wed, 4 Mar 2009 09:09:50 -0500 Message-ID: <49AE8BA8.3080504@redhat.com> Date: Wed, 04 Mar 2009 15:09:44 +0100 From: Zdenek Kabelac Organization: Red Hat User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: Markus CC: linux-kernel@vger.kernel.org, Wu Fengguang , linux-mm@kvack.org Subject: Re: drop_caches ... References: <200903041057.34072.M4rkusXXL@web.de> <20090304115702.GA17565@localhost> <49AE74E6.1060008@redhat.com> <200903041447.49534.M4rkusXXL@web.de> In-Reply-To: <200903041447.49534.M4rkusXXL@web.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4884 Lines: 129 Markus napsal(a): >>>>>>> The memory mapped pages won't be dropped in this way. >>>>>>> "cat /proc/meminfo" will show you the number of mapped pages. >>>>>> # sync ; echo 3 > /proc/sys/vm/drop_caches ; free -m ; >>>> cat /proc/meminfo >>>>>> total used free shared buffers >>>>>> cached >>>>>> Mem: 3950 3262 688 0 0 >>>>>> 359 >>>>>> -/+ buffers/cache: 2902 1047 >>>>>> Swap: 5890 1509 4381 >>>>>> MemTotal: 4045500 kB >>>>>> MemFree: 705180 kB >>>>>> Buffers: 508 kB >>>>>> Cached: 367748 kB >>>>>> SwapCached: 880744 kB >>>>>> Active: 1555032 kB >>>>>> Inactive: 1634868 kB >>>>>> Active(anon): 1527100 kB >>>>>> Inactive(anon): 1607328 kB >>>>>> Active(file): 27932 kB >>>>>> Inactive(file): 27540 kB >>>>>> Unevictable: 816 kB >>>>>> Mlocked: 0 kB >>>>>> SwapTotal: 6032344 kB >>>>>> SwapFree: 4486496 kB >>>>>> Dirty: 0 kB >>>>>> Writeback: 0 kB >>>>>> AnonPages: 2378112 kB >>>>>> Mapped: 52196 kB >>>>>> Slab: 65640 kB >>>>>> SReclaimable: 46192 kB >>>>>> SUnreclaim: 19448 kB >>>>>> PageTables: 28200 kB >>>>>> NFS_Unstable: 0 kB >>>>>> Bounce: 0 kB >>>>>> WritebackTmp: 0 kB >>>>>> CommitLimit: 8055092 kB >>>>>> Committed_AS: 4915636 kB >>>>>> VmallocTotal: 34359738367 kB >>>>>> VmallocUsed: 44580 kB >>>>>> VmallocChunk: 34359677239 kB >>>>>> DirectMap4k: 3182528 kB >>>>>> DirectMap2M: 1011712 kB >>>>>> >>>>>> The cached reduced to 359 MB (after the dropping). >>>>>> I dont know where to read the "number of mapped pages". >>>>>> "Mapped" is about 51 MB. >>>>> Does your tmpfs store lots of files? >>>> Dont think so: >>>> >>>> # df -h >>>> Filesystem Size Used Avail Use% Mounted on >>>> /dev/md6 14G 8.2G 5.6G 60% / >>>> udev 10M 304K 9.8M 3% /dev >>>> cachedir 4.0M 100K 4.0M 3% /lib64/splash/cache >>>> /dev/md4 19G 15G 3.1G 83% /home >>>> /dev/md3 8.3G 4.5G 3.9G 55% /usr/portage >>>> shm 2.0G 0 2.0G 0% /dev/shm >>>> /dev/md1 99M 19M 76M 20% /boot >>>> >>>> # mount >>>> /dev/md6 on / type ext3 (rw,noatime,nodiratime,barrier=0) >>>> /proc on /proc type proc (rw,noexec,nosuid,noatime,nodiratime) >>>> sysfs on /sys type sysfs (rw,nosuid,nodev,noexec) >>>> udev on /dev type tmpfs (rw,nosuid,size=10240k,mode=755) >>>> devpts on /dev/pts type devpts (rw,nosuid,noexec,gid=5,mode=620) >>>> cachedir on /lib64/splash/cache type tmpfs (rw,size=4096k,mode=644) >>>> /dev/md4 on /home type ext3 (rw,noatime,nodiratime,barrier=0) >>>> /dev/md3 on /usr/portage type ext4 > (rw,noatime,nodiratime,barrier=0) >>>> shm on /dev/shm type tmpfs (rw,noexec,nosuid,nodev) >>>> usbfs on /proc/bus/usb type usbfs >>>> (rw,noexec,nosuid,devmode=0664,devgid=85) >>>> automount(pid6507) on /mnt/.autofs/misc type autofs >>>> (rw,fd=4,pgrp=6507,minproto=2,maxproto=4) >>>> automount(pid6521) on /mnt/.autofs/usb type autofs >>>> (rw,fd=4,pgrp=6521,minproto=2,maxproto=4) >>>> /dev/md1 on /boot type ext2 (rw,noatime,nodiratime) >>>> >>>> I dont know what exactly all that memory is used for. It varies > from >>>> about 300 MB to up to one GB. >>>> Tell me where to look and I will! >>> So you don't have lots of mapped pages(Mapped=51M) or tmpfs files. > It's >>> strange to me that there are so many undroppable cached > pages(Cached=359M), >>> and most of them lie out of the LRU queue(Active+Inactive > file=53M)... >>> Anyone have better clues on these 'hidden' pages? >> Maybe try this: >> >> cat /proc/`pidof X`/smaps | grep drm | wc -l >> >> you will see some growing numbers. >> >> Also check cat /proc/dri/0/gem_objects >> there should be some number # object bytes - which should be close to > your >> missing cached pages. >> >> >> If you are using Intel GEM driver - there is some unlimited caching > issue >> see: http://bugs.freedesktop.org/show_bug.cgi?id=20404 >> > # cat /proc/`pidof X`/smaps | grep drm | wc -l > 0 > # cat /proc/dri/0/gem_objects > cat: /proc/dri/0/gem_objects: No such file or directory > > I use Xorg 1.3 with an nvidia gpu. Dont know if I use a "Intel GEM > driver". > Are you using binary driver from NVidia ?? Maybe you should ask authors of this binary blob ? Could you try to use for a while Vesa driver to see, if you are able to get same strange results ? Zdenek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/