* Dave Chinner: > [cc Michal, linux-mm@xxxxxxxxx] > > On Tue, Sep 20, 2016 at 10:56:31PM +0200, Florian Weimer wrote: >> * Dave Chinner: >> >> >> OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME >> >> 4121208 4121177 99% 0.88K 1030302 4 4121208K xfs_inode >> >> 986286 985229 99% 0.19K 46966 21 187864K dentry >> >> 723255 723076 99% 0.10K 18545 39 74180K buffer_head >> >> 270263 269251 99% 0.56K 38609 7 154436K radix_tree_node >> >> 140310 67409 48% 0.38K 14031 10 56124K mnt_cache >> > >> > That's not odd at all. It means your workload is visiting millions >> > on inodes in your filesystem between serious memory pressure events. >> >> Okay. >> >> >> (I have attached the /proc/meminfo contents in case it offers further >> >> clues.) >> >> >> >> Confronted with large memory allocations (from “make -j12” and >> >> compiling GCC, so perhaps ~8 GiB of memory), the OOM killer kicks in >> >> and kills some random process. I would have expected that some >> >> xfs_inodes are freed instead. >> > >> > The oom killer is unreliable and often behaves very badly, and >> > that's typicaly not an XFS problem. >> > >> > What is the full output off the oom killer invocations from dmesg? >> >> I've attached the dmesg output (two events). > > Copied from the traces you attached (I've left them intact below for > reference): > >> [51669.515086] make invoked oom-killer: gfp_mask=0x27000c0(GFP_KERNEL_ACCOUNT|__GFP_NOTRACK), order=2, oom_score_adj=0 >> [51669.515092] CPU: 1 PID: 1202 Comm: make Tainted: G I 4.7.1fw #1 >> [51669.515093] Hardware name: System manufacturer System Product Name/P6X58D-E, BIOS 0701 05/10/2011 >> [51669.515095] 0000000000000000 ffffffff812a7d39 0000000000000000 0000000000000000 >> [51669.515098] ffffffff8114e4da ffff880018707d98 0000000000000000 000000000066ca81 >> [51669.515100] ffffffff8170e88d ffffffff810fe69e ffff88033fc38728 0000000200000006 >> [51669.515102] Call Trace: >> [51669.515108] [<ffffffff812a7d39>] ? dump_stack+0x46/0x5d >> [51669.515113] [<ffffffff8114e4da>] ? dump_header.isra.12+0x51/0x176 >> [51669.515116] [<ffffffff810fe69e>] ? oom_kill_process+0x32e/0x420 >> [51669.515119] [<ffffffff811003a0>] ? page_alloc_cpu_notify+0x40/0x40 >> [51669.515120] [<ffffffff810fdcdc>] ? find_lock_task_mm+0x2c/0x70 >> [51669.515122] [<ffffffff810fea6d>] ? out_of_memory+0x28d/0x2d0 >> [51669.515125] [<ffffffff81103137>] ? __alloc_pages_nodemask+0xb97/0xc90 >> [51669.515128] [<ffffffff81076d9c>] ? copy_process.part.54+0xec/0x17a0 >> [51669.515131] [<ffffffff81123318>] ? handle_mm_fault+0xaa8/0x1900 >> [51669.515133] [<ffffffff81078614>] ? _do_fork+0xd4/0x320 >> [51669.515137] [<ffffffff81084ecc>] ? __set_current_blocked+0x2c/0x40 >> [51669.515140] [<ffffffff810013ce>] ? do_syscall_64+0x3e/0x80 >> [51669.515144] [<ffffffff8151433c>] ? entry_SYSCALL64_slow_path+0x25/0x25 > ..... >> [51669.515194] DMA: 1*4kB (U) 1*8kB (U) 1*16kB (U) 0*32kB 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15900kB >> [51669.515202] DMA32: 45619*4kB (UME) 73*8kB (UM) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 183060kB >> [51669.515209] Normal: 39979*4kB (UE) 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 159916kB > ..... > > Alright, that's what I suspected. high order allocation for a new > kernel stack and memory is so fragmented that a contiguous > allocation fails. Really, this is a memory reclaim issue, not an XFS > issue. There is lots of reclaimable memory available, but memory > reclaim is: > > a) not trying hard enough to reclaim reclaimable memory; and > b) not waiting for memory compaction to rebuild contiguous > memory regions for high order allocations. > > Instead, it is declaring OOM and kicking the killer to free memory > held busy userspace. Thanks. I have put the full kernel config here: <http://static.enyo.de/fw/volatile/config-4.7.1fw> _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
