Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752651Ab3IQLUV (ORCPT ); Tue, 17 Sep 2013 07:20:21 -0400 Received: from gmmr7.centrum.cz ([46.255.225.249]:54087 "EHLO gmmr7.centrum.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752393Ab3IQLUU (ORCPT ); Tue, 17 Sep 2013 07:20:20 -0400 To: =?utf-8?q?Johannes_Weiner?= Subject: =?utf-8?q?Re=3A_=5Bpatch_0=2F7=5D_improve_memcg_oom_killer_robustness_v2?= Date: Tue, 17 Sep 2013 13:20:17 +0200 From: "azurIt" Cc: =?utf-8?q?Michal_Hocko?= , =?utf-8?q?Andrew_Morton?= , =?utf-8?q?David_Rientjes?= , =?utf-8?q?KAMEZAWA_Hiroyuki?= , =?utf-8?q?KOSAKI_Motohiro?= , , , , , References: <20130911200426.GO856@cmpxchg.org>, <20130914124831.4DD20346@pobox.sk>, <20130916134014.GA3674@dhcp22.suse.cz>, <20130916160119.2E76C2A1@pobox.sk>, <20130916140607.GC3674@dhcp22.suse.cz>, <20130916161316.5113F6E7@pobox.sk>, <20130916145744.GE3674@dhcp22.suse.cz>, <20130916170543.77F1ECB4@pobox.sk>, <20130916152548.GF3674@dhcp22.suse.cz>, <20130916225246.A633145B@pobox.sk> <20130917000244.GD3278@cmpxchg.org> In-Reply-To: <20130917000244.GD3278@cmpxchg.org> X-Mailer: Centrum Email 5.3 X-Priority: 3 X-Original-From: azurit@pobox.sk MIME-Version: 1.0 Message-Id: <20130917132017.5B266A87@pobox.sk> X-Maser: brud Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3248 Lines: 56 > CC: "Michal Hocko" , "Andrew Morton" , "David Rientjes" , "KAMEZAWA Hiroyuki" , "KOSAKI Motohiro" , linux-mm@kvack.org, cgroups@vger.kernel.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org >On Mon, Sep 16, 2013 at 10:52:46PM +0200, azurIt wrote: >> > CC: "Johannes Weiner" , "Andrew Morton" , "David Rientjes" , "KAMEZAWA Hiroyuki" , "KOSAKI Motohiro" , linux-mm@kvack.org, cgroups@vger.kernel.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org >> >On Mon 16-09-13 17:05:43, azurIt wrote: >> >> > CC: "Johannes Weiner" , "Andrew Morton" , "David Rientjes" , "KAMEZAWA Hiroyuki" , "KOSAKI Motohiro" , linux-mm@kvack.org, cgroups@vger.kernel.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org >> >> >On Mon 16-09-13 16:13:16, azurIt wrote: >> >> >[...] >> >> >> >You can use sysrq+l via serial console to see tasks hogging the CPU or >> >> >> >sysrq+t to see all the existing tasks. >> >> >> >> >> >> >> >> >> Doesn't work here, it just prints 'l' resp. 't'. >> >> > >> >> >I am using telnet for accessing my serial consoles exported by >> >> >the multiplicator or KVM and it can send sysrq via ctrl+t (Send >> >> >Break). Check your serial console setup. >> >> >> >> >> >> >> >> I'm using Raritan KVM and i created keyboard macro 'sysrq + l' resp. >> >> 'sysrq + t'. I'm also unable to use it on my local PC. Maybe it needs >> >> to be enabled somehow? >> > >> >Probably yes. echo 1 > /proc/sys/kernel/sysrq should enable all sysrq >> >commands. You can select also some of them (have a look at >> >Documentation/sysrq.txt for more information) >> >> >> Now it happens again and i was just looking on the server's >> htop. I'm sure that this time it was only one process (apache) >> running under user account (not root). It was taking about 100% CPU >> (about 100% of one core). I was able to kill it by hand inside htop >> but everything was very slow, server load was immediately on >> 500. I'm sure it must be related to that Johannes kernel patches >> because i'm also using i/o throttling in cgroups via Block IO >> controller so users are unable to create such a huge I/O. I will try >> to take stacks of processes but i'm not able to identify the >> problematic process so i will have to take them from *all* apache >> processes while killing them. > >It would be fantastic if you could capture those stacks. sysrq+t >captures ALL of them in one go and drops them into your syslog. > >/proc//stack for individual tasks works too. Btw, this is how it looked like: http://watchdog.sk/lkml/htop2.jpg azur -- 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/