Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753801AbZIKDVx (ORCPT ); Thu, 10 Sep 2009 23:21:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753700AbZIKDVw (ORCPT ); Thu, 10 Sep 2009 23:21:52 -0400 Received: from mga03.intel.com ([143.182.124.21]:39535 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752576AbZIKDVv (ORCPT ); Thu, 10 Sep 2009 23:21:51 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.44,368,1249282800"; d="scan'208";a="186443749" Date: Fri, 11 Sep 2009 11:21:47 +0800 From: Wu Fengguang To: Clemens Eisserer Cc: linux-kernel@vger.kernel.org Subject: Re: [ARM9] OOM with plenty of free swap space? Message-ID: <20090911032147.GH6267@localhost> References: <194f62550909050551n3ac70080u528ae8a9322d4a5a@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <194f62550909050551n3ac70080u528ae8a9322d4a5a@mail.gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4761 Lines: 119 Hi Clemens, On Sat, Sep 05, 2009 at 08:51:24AM -0400, Clemens Eisserer wrote: > Hi, > > I am using a Nokia-770 internet tablet (ARM9) running a 2.6.16.27 2.6.16 is a pretty old kernel. > (precompiled wlan driver) kernel as a small buissness server > (postgres, tor, samba, lighttp). > > It works quite well, however I recently discovered that postgres was > killed by the oom killer (log below), > although plenty of free swap was available. Its a really small > database so it should easily fit in the 64mb main memory. > > Any idea what could the reason for this OOM? > > Thank you in advance, Clemens > > > [17676.783874] oom-killer: gfp_mask=0x201d2, order=0 It's combination of HIGHMEM,WAIT,IO,FS,COLD, which is not easy to fail. > [17676.797241] [] (dump_stack+0x0/0x14) from [] > (out_of_memory+0x40/0x1d8) > [17676.797393] [] (out_of_memory+0x0/0x1d8) from > [] (__alloc_pages+0x240/0x2c4) > [17676.797515] [] (__alloc_pages+0x0/0x2c4) from > [] (__do_page_cache_readahead+0x150/0x324) > [17676.797637] [] (__do_page_cache_readahead+0x0/0x324) from > [] (do_page_cache_readahead+0x64/0x70) > [17676.797760] [] (do_page_cache_readahead+0x0/0x70) from > [] (filemap_nopage+0x190/0x3ec) > [17676.797943] r7 = 00000000 r6 = 00219560 r5 = 00000000 r4 = > C25E0000 > [17676.798004] [] (filemap_nopage+0x0/0x3ec) from This is a mmap read-around, its ra size would be <= 128KB. > [] (__handle_mm_fault+0x2fc/0x96c) > [17676.798126] [] (__handle_mm_fault+0x0/0x96c) from > [] (do_page_fault+0xe4/0x214) > [17676.798248] [] (do_page_fault+0x0/0x214) from > [] (do_DataAbort+0x3c/0xa4) > [17676.798339] [] (do_DataAbort+0x0/0xa4) from [] > (ret_from_exception+0x0/0x10) > [17676.798461] r8 = 00000000 r7 = 40639540 r6 = 40639560 r5 = > 00000001 > [17676.798553] r4 = FFFFFFFF > [17676.798583] Mem-info: > [17676.798614] DMA per-cpu: > [17676.798675] cpu 0 hot: high 18, batch 3 used:2 > [17676.798706] cpu 0 cold: high 6, batch 1 used:0 > [17676.798767] DMA32 per-cpu: empty > [17676.798797] Normal per-cpu: empty > [17676.798828] HighMem per-cpu: empty > [17676.798950] Free pages: 1172kB (0kB HighMem) > [17676.799011] Active:5576 inactive:6815 dirty:0 writeback:231 > unstable:0 free:293 slab:1257 mapped:12129 pagetables:374 Most LRU pages are mapped: active+inactive-writeback=6815+5576-231=12160 ~= 12129=mapped > [17676.799133] DMA free:1172kB min:1024kB low:1280kB high:1536kB > active:22304kB inactive:27260kB present:65536kB pages_scanned:91 > all_unreclaimable? no > [17676.799224] lowmem_reserve[]: 0 0 0 0 > [17676.799285] DMA32 free:0kB min:0kB low:0kB high:0kB active:0kB > inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no > [17676.799377] lowmem_reserve[]: 0 0 0 0 > [17676.799468] Normal free:0kB min:0kB low:0kB high:0kB active:0kB > inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no > [17676.799530] lowmem_reserve[]: 0 0 0 0 > [17676.799621] HighMem free:0kB min:128kB low:128kB high:128kB > active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? > no > [17676.799682] lowmem_reserve[]: 0 0 0 0 > [17676.799743] DMA: 33*4kB 4*8kB 1*16kB 1*32kB 1*64kB 1*128kB 1*256kB > 1*512kB 0*1024kB 0*2048kB 0*4096kB = 1172kB > [17676.799896] DMA32: empty > [17676.799926] Normal: empty > [17676.799957] HighMem: empty > [17676.800018] Swap cache: add 12847, delete 11756, find 42323/43010, race 0+0 > [17676.800079] Free swap = 167716kB > [17676.800109] Total swap = 198272kB > [17676.800170] Free swap: 167716kB > [17676.804534] 16384 pages of RAM > [17676.804565] 638 free pages > [17676.804595] 1096 reserved pages > [17676.804626] 1257 slab pages > [17676.804656] 19580 pages shared > [17676.804718] 1091 pages swap cached There are ~30MB pages swapped, and another ~4MB in page cache. So the system is moderately stressed. It may be a vmscan bug, I'd recommend to try a recent kernel and see if things improved. Thanks, Fengguang > [17676.805267] Out of Memory: Kill process 1535 (postgres) score 11478 > and children. > [17676.805358] Out of memory: Killed process 1537 (postgres). > -- > 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/ -- 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/