From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 4130A8D003B for ; Wed, 20 Apr 2011 01:53:37 -0400 (EDT) Received: by iyh42 with SMTP id 42so511068iyh.14 for ; Tue, 19 Apr 2011 22:53:35 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: Date: Wed, 20 Apr 2011 14:53:35 +0900 Message-ID: Subject: Re: [HELP] OOM:Page allocation fragment issue From: Minchan Kim Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: TAO HU Cc: linux-mm@kvack.org, linux-input@vger.kernel.org, Christoph Lameter , Pekka Enberg , Matt Mackall On Wed, Apr 20, 2011 at 1:47 PM, Minchan Kim wrote: > On Wed, Apr 20, 2011 at 11:59 AM, TAO HU wrote: >> Hi, All >> >> I got a issue that kmalloc() fails to allocate 32-K page while there >> are still pretty much total memory available (60+MB). >> Any suggestions? Any thing I can tune to reduced the failure cases? >> >> It happens with 2.6.35 kernel >> >> <4>[ 6232.631622] getevent invoked oom-killer: gfp_mask=3D0xd0, order=3D= 3, oom_adj=3D0 >> <4>[ 6232.639312] [] (unwind_backtrace+0x0/0xf0) from >> [] (dump_header.clone.1+0x50/0x84) >> <4>[ 6232.649597] [] (dump_header.clone.1+0x50/0x84) from >> [] (oom_kill_process.clone.0+0x34/0xec) >> <4>[ 6232.660705] [] (oom_kill_process.clone.0+0x34/0xec) >> from [] (__out_of_memory+0x15c/0x184) >> <4>[ 6232.671630] [] (__out_of_memory+0x15c/0x184) from >> [] (out_of_memory+0x94/0xd4) >> <4>[ 6232.681488] [] (out_of_memory+0x94/0xd4) from >> [] (__alloc_pages_nodemask+0x4c4/0x6e8) >> <4>[ 6232.692016] [] (__alloc_pages_nodemask+0x4c4/0x6e8) >> from [] (cache_grow.clone.0+0xac/0x3e4) >> <4>[ 6232.703125] [] (cache_grow.clone.0+0xac/0x3e4) from >> [] (__kmalloc+0x3ec/0x6c4) >> <4>[ 6232.712982] [] (__kmalloc+0x3ec/0x6c4) from >> [] (evdev_open+0x94/0x1ec) >> <4>[ 6232.722137] [] (evdev_open+0x94/0x1ec) from >> [] (input_open_file+0x184/0x2d8) >> <4>[ 6232.731781] [] (input_open_file+0x184/0x2d8) from >> [] (chrdev_open+0x20c/0x234) >> <4>[ 6232.741638] [] (chrdev_open+0x20c/0x234) from >> [] (__dentry_open+0x200/0x324) >> <4>[ 6232.751281] [] (__dentry_open+0x200/0x324) from >> [] (nameidata_to_filp+0x3c/0x50) >> <4>[ 6232.761322] [] (nameidata_to_filp+0x3c/0x50) from >> [] (do_last+0x4c8/0x5ec) >> <4>[ 6232.770782] [] (do_last+0x4c8/0x5ec) from [] >> (do_filp_open+0x184/0x514) >> <4>[ 6232.779937] [] (do_filp_open+0x184/0x514) from >> [] (do_sys_open+0x58/0x18c) >> <4>[ 6232.789428] [] (do_sys_open+0x58/0x18c) from >> [] (ret_fast_syscall+0x0/0x30) >> <4>[ 6232.798980] Mem-info: >> <4>[ 6232.801483] Normal per-cpu: >> <4>[ 6232.804565] CPU =C2=A0 =C2=A00: hi: =C2=A0186, btch: =C2=A031 usd:= =C2=A015 >> <4>[ 6232.809844] active_anon:34424 inactive_anon:36745 isolated_anon:3 >> <4>[ 6232.809875] =C2=A0active_file:2 inactive_file:0 isolated_file:65 >> <4>[ 6232.809875] =C2=A0unevictable:95 dirty:0 writeback:0 unstable:0 >> <4>[ 6232.809906] =C2=A0free:16133 slab_reclaimable:1274 slab_unreclaima= ble:3892 >> <4>[ 6232.809906] =C2=A0mapped:8809 shmem:263 pagetables:4657 bounce:0 >> <4>[ 6232.841766] Normal free:64532kB min:2884kB low:3604kB >> high:4324kB active_anon:137696kB inactive_anon:146980kB >> active_file:8kB inactive_file:0kB unevictable:380kB > > There are lots of anon pages but few file pages. > >> isolated(anon):12kB isolated(file):260kB present:520192kB mlocked:0kB >> dirty:0kB writeback:0kB mapped:35236kB shmem:1052kB >> slab_reclaimable:5096kB slab_unreclaimable:15568kB kernel_stack:6544kB >> pagetables:18628kB unstable:0kB bounce:0kB writeback_tmp:0kB >> pages_scanned:34 all_unreclaimable? no >> <4>[ 6232.885314] lowmem_reserve[]: 0 0 0 >> <4>[ 6232.889190] Normal: 10659*4kB 2735*8kB 1*16kB 0*32kB 0*64kB >> 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB =3D 64532kB > > There isn't any pages of bigger 32K in your system. > Memory fragmentation is high. > >> <4>[ 6232.901367] 397 total pagecache pages >> <4>[ 6232.905395] 0 pages in swap cache >> <4>[ 6232.909027] Swap cache stats: add 0, delete 0, find 0/0 >> <4>[ 6232.914764] Free swap =C2=A0=3D 0kB >> <4>[ 6232.917968] Total swap =3D 0kB > > You don't have swap so VM can't reclaim anon pages to get a contiguous pa= ge. > >> <4>[ 6232.945617] 131072 pages of RAM >> <4>[ 6232.949127] 17229 free pages >> <4>[ 6232.952270] 22953 reserved pages >> <4>[ 6232.955810] 5166 slab pages >> <4>[ 6232.958892] 123153 pages shared >> <4>[ 6232.962341] 0 pages swap cached >> > > It means your system has 512M but 68M is reserved. > So you can use just 444M but anon is 278M. As I said, you can't > reclaim anon paes. > There is 67M free page but you can't use it as it's small pages but > you want big page. > slab : 20M page table : 18M kernel stack : 6M. > So 278 + 67 + 20 + 18 + 6 =3D 389M. > 512M - 68M =3D 444. > Where is (444 - 389)? > I guess 55M is used by device driver and kernel. It's not accountable > in current kernel. > > Solution > 1. use CONFIG_COMPACTION=3Dy if you don't use. > 2: consume small memory by application or device driver > 3: use swap for reclaimaing anon pages > 4 : buy bigger memory One more solution is to use zram(Compressed RAM block device support) device with swap. old name is compcache. You can refer drivers/staging/zram Good luck. --=20 Kind regards, Minchan Kim -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org