From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755531Ab1HXGM5 (ORCPT ); Wed, 24 Aug 2011 02:12:57 -0400 Received: from server655-han.de-nserver.de ([85.158.177.45]:56432 "EHLO server655-han.de-nserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752956Ab1HXGMy (ORCPT ); Wed, 24 Aug 2011 02:12:54 -0400 X-Greylist: delayed 400 seconds by postgrey-1.27 at vger.kernel.org; Wed, 24 Aug 2011 02:12:54 EDT Message-ID: <4E5494D4.1050605@profihost.ag> Date: Wed, 24 Aug 2011 08:06:12 +0200 From: Stefan Priebe - Profihost AG User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.18) Gecko/20110617 Thunderbird/3.1.11 MIME-Version: 1.0 To: LKML Subject: slow performance on disk/network i/o full speed after drop_caches Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-User-Auth: Auth by hostmaster@profihost.com through 85.158.179.66 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dear list, i hope this is the correct list to write to if it would be nice to give me a hint where i can ask. Kernel: 2.6.38 I'm seeing some strange problems on some of our servers after upgrading to 2.6.38. I'm copying a 1GB file via scp from Machine A to Machine B. When B is freshly booted the file transfer is done with about 80 to 85 Mb/s. I can repeat that various times to performance degrease. Then after some days copying is only done with about 900kb/s up to 3Mb/s going up and down while transfering the file. When i then do drop_caches it works again on 80Mb/s. sync && echo 3 >/proc/sys/vm/drop_caches && sleep 2 && echo 0 >/proc/sys/vm/drop_caches Attached is also an output of meminfo before and after drop_caches. What's going on here? MemFree is pretty high. Please CC me i'm not on list. Greets Stefan # before drop_caches # cat /proc/meminfo MemTotal: 8185544 kB MemFree: 6670292 kB Buffers: 105164 kB Cached: 166672 kB SwapCached: 0 kB Active: 728308 kB Inactive: 567428 kB Active(anon): 639204 kB Inactive(anon): 394932 kB Active(file): 89104 kB Inactive(file): 172496 kB Unevictable: 2976 kB Mlocked: 2992 kB SwapTotal: 1464316 kB SwapFree: 1464316 kB Dirty: 52 kB Writeback: 0 kB AnonPages: 1026920 kB Mapped: 54208 kB Shmem: 8380 kB Slab: 80724 kB SReclaimable: 22844 kB SUnreclaim: 57880 kB KernelStack: 2872 kB PageTables: 35448 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 5557088 kB Committed_AS: 6187972 kB VmallocTotal: 34359738367 kB VmallocUsed: 292360 kB VmallocChunk: 34359425327 kB HardwareCorrupted: 0 kB DirectMap4k: 5632 kB DirectMap2M: 2082816 kB DirectMap1G: 6291456 kB # cat /proc/meminfo MemTotal: 8185544 kB MemFree: 6888060 kB Buffers: 372 kB Cached: 61492 kB SwapCached: 0 kB Active: 659156 kB Inactive: 426664 kB Active(anon): 638892 kB Inactive(anon): 395200 kB Active(file): 20264 kB Inactive(file): 31464 kB Unevictable: 2976 kB Mlocked: 2992 kB SwapTotal: 1464316 kB SwapFree: 1464316 kB Dirty: 0 kB Writeback: 0 kB AnonPages: 1026952 kB Mapped: 54236 kB Shmem: 8316 kB Slab: 70616 kB SReclaimable: 12264 kB SUnreclaim: 58352 kB KernelStack: 2864 kB PageTables: 35448 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 5557088 kB Committed_AS: 6187932 kB VmallocTotal: 34359738367 kB VmallocUsed: 292360 kB VmallocChunk: 34359425327 kB HardwareCorrupted: 0 kB DirectMap4k: 5632 kB DirectMap2M: 2082816 kB DirectMap1G: 6291456 kB