(switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). A 2100 second page allocation stall! On Fri, 20 Jan 2017 15:14:13 +0000 bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=192981 > > Bug ID: 192981 > Summary: page allocation stalls > Product: Memory Management > Version: 2.5 > Kernel Version: 4.9 > Hardware: x86-64 > OS: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Page Allocator > Assignee: akpm@xxxxxxxxxxxxxxxxxxxx > Reporter: apolyakov@xxxxxxxx > Regression: No > > Created attachment 252621 > --> https://bugzilla.kernel.org/attachment.cgi?id=252621&action=edit > netconsole log with page allocation stalls > > We have been experiencing page allocation stalls regularly on our machines used > as backup servers (many disks, mostly running rsync and rm). > > A notable one (2102516ms): > > 2017-01-17T11:08:33.754562+03:00 storage8 [335170.452601] rsync: > 2017-01-17T11:08:33.754574+03:00 page allocation stalls for 2102516ms, order:0 > 2017-01-17T11:08:33.754825+03:00 storage8 , > mode:0x26040d0(GFP_TEMPORARY|__GFP_COMP|__GFP_NOTRACK) > 2017-01-17T11:08:33.755094+03:00 storage8 [335170.452896] CPU: 2 PID: 20383 > Comm: rsync Tainted: G O 4.9.0-0-beget-vanilla #1 > 2017-01-17T11:08:33.755337+03:00 storage8 [335170.453156] Hardware name: > Supermicro X8DTL/X8DTL, BIOS 2.1b 11/16/2012 > 2017-01-17T11:08:33.755379+03:00 storage8 [335170.453414] 0000000000000000 > 2017-01-17T11:08:33.755379+03:00 storage8 ffffffff92441e0b > 2017-01-17T11:08:33.755393+03:00 storage8 ffff8c4b0f30f430 > 2017-01-17T11:08:33.755484+03:00 storage8 0000000000000001 > 2017-01-17T11:08:33.755600+03:00 storage8 > 2017-01-17T11:08:33.755603+03:00 storage8 [335170.453681] ffffffff92c3d1f8 > 2017-01-17T11:08:33.755643+03:00 storage8 ffffffff92189594 > 2017-01-17T11:08:33.755648+03:00 storage8 ffff8c4b0f315088 > 2017-01-17T11:08:33.755754+03:00 storage8 026040d0026040d0 > 2017-01-17T11:08:33.755874+03:00 storage8 > 2017-01-17T11:08:33.755874+03:00 storage8 [335170.453951] 0000000000000020 > 2017-01-17T11:08:33.755880+03:00 storage8 0000000000000010 > 2017-01-17T11:08:33.755913+03:00 storage8 ffffa449d15cb7f8 > 2017-01-17T11:08:33.756024+03:00 storage8 ffffa449d15cb7a8 > 2017-01-17T11:08:33.756163+03:00 storage8 > 2017-01-17T11:08:33.756278+03:00 storage8 [335170.454216] Call Trace: > 2017-01-17T11:08:33.756401+03:00 storage8 [335170.454347] [<ffffffff92441e0b>] > ? dump_stack+0x47/0x5c > 2017-01-17T11:08:33.756537+03:00 storage8 [335170.454479] [<ffffffff92189594>] > ? warn_alloc+0x134/0x150 > 2017-01-17T11:08:33.756677+03:00 storage8 [335170.454612] [<ffffffff92189f2d>] > ? __alloc_pages_nodemask+0x90d/0xdb0 > 2017-01-17T11:08:33.756808+03:00 storage8 [335170.454753] [<ffffffff923a5da4>] > ? _xfs_trans_bjoin+0xe4/0x110 > 2017-01-17T11:08:33.756955+03:00 storage8 [335170.454892] [<ffffffff921d76fa>] > ? alloc_pages_current+0x9a/0x120 > 2017-01-17T11:08:33.757096+03:00 storage8 [335170.455027] [<ffffffff921de440>] > ? new_slab+0x550/0x5f0 > 2017-01-17T11:08:33.757218+03:00 storage8 [335170.455162] [<ffffffff921df2eb>] > ? ___slab_alloc.isra.59+0x3db/0x500 > 2017-01-17T11:08:33.757346+03:00 storage8 [335170.455297] [<ffffffff923a683a>] > ? xfs_trans_brelse+0x1aa/0x270 > 2017-01-17T11:08:33.757489+03:00 storage8 [335170.455427] [<ffffffff921f4612>] > ? memcg_kmem_get_cache+0x72/0x170 > 2017-01-17T11:08:33.757632+03:00 storage8 [335170.455567] [<ffffffff92447837>] > ? __radix_tree_create+0xa7/0x320 > 2017-01-17T11:08:33.757762+03:00 storage8 [335170.455706] [<ffffffff92200be5>] > ? __slab_alloc.isra.60+0xe/0x12 > 2017-01-17T11:08:33.757897+03:00 storage8 [335170.455842] [<ffffffff921df5b0>] > ? kmem_cache_alloc+0x1a0/0x1b0 > 2017-01-17T11:08:33.758034+03:00 storage8 [335170.455978] [<ffffffff9221b746>] > ? __d_alloc+0x26/0x1c0 > 2017-01-17T11:08:33.758160+03:00 storage8 [335170.456108] [<ffffffff9221bb67>] > ? d_alloc+0x17/0x80 > 2017-01-17T11:08:33.758290+03:00 storage8 [335170.456236] [<ffffffff9221bdf1>] > ? d_alloc_parallel+0x31/0x4b0 > 2017-01-17T11:08:33.758429+03:00 storage8 [335170.456370] [<ffffffff9220f836>] > ? lookup_fast+0x56/0x2f0 > 2017-01-17T11:08:33.758579+03:00 storage8 [335170.456505] [<ffffffff923804de>] > ? xfs_iunlock+0x17e/0x210 > 2017-01-17T11:08:33.758694+03:00 storage8 [335170.456635] [<ffffffff922237f2>] > ? legitimize_mnt+0x12/0x40 > 2017-01-17T11:08:33.758818+03:00 storage8 [335170.456770] [<ffffffff9220d8f0>] > ? lookup_slow+0x80/0x170 > 2017-01-17T11:08:33.758955+03:00 storage8 [335170.456897] [<ffffffff9220fd08>] > ? walk_component+0x1a8/0x270 > 2017-01-17T11:08:33.759086+03:00 storage8 [335170.457024] [<ffffffff92210398>] > ? path_lookupat+0x48/0xf0 > 2017-01-17T11:08:33.759200+03:00 storage8 [335170.457153] [<ffffffff92212e75>] > ? filename_lookup+0xb5/0x190 > 2017-01-17T11:08:33.759336+03:00 storage8 [335170.457282] [<ffffffff92474992>] > ? strncpy_from_user+0x42/0x140 > 2017-01-17T11:08:33.759462+03:00 storage8 [335170.457411] [<ffffffff9221305b>] > ? getname_flags+0x7b/0x200 > 2017-01-17T11:08:33.759593+03:00 storage8 [335170.457538] [<ffffffff92208b66>] > ? vfs_fstatat+0x46/0x90 > 2017-01-17T11:08:33.759719+03:00 storage8 [335170.457666] [<ffffffff9221aaf4>] > ? dput+0x34/0x200 > 2017-01-17T11:08:33.759859+03:00 storage8 [335170.457793] [<ffffffff92208d47>] > ? SyS_newlstat+0x17/0x30 > 2017-01-17T11:08:33.759977+03:00 storage8 [335170.457923] [<ffffffff9282b7a0>] > ? entry_SYSCALL_64_fastpath+0x13/0x94 > > > # sysctl vm > vm.admin_reserve_kbytes = 1048576 > vm.block_dump = 0 > error: permission denied on key 'vm.compact_memory' > vm.compact_unevictable_allowed = 1 > vm.dirty_background_bytes = 0 > vm.dirty_background_ratio = 1 > vm.dirty_bytes = 0 > vm.dirty_expire_centisecs = 1000 > vm.dirty_ratio = 1 > vm.dirty_writeback_centisecs = 100 > vm.dirtytime_expire_seconds = 43200 > vm.drop_caches = 0 > vm.extfrag_threshold = 500 > vm.hugepages_treat_as_movable = 0 > vm.hugetlb_shm_group = 0 > vm.laptop_mode = 0 > vm.legacy_va_layout = 0 > vm.lowmem_reserve_ratio = 128 128 16 > vm.max_map_count = 65530 > vm.memory_failure_early_kill = 0 > vm.memory_failure_recovery = 1 > vm.min_free_kbytes = 4194304 > vm.min_slab_ratio = 1 > vm.min_unmapped_ratio = 1 > vm.mmap_min_addr = 65536 > vm.mmap_rnd_bits = 28 > vm.nr_hugepages = 0 > vm.nr_hugepages_mempolicy = 0 > vm.nr_overcommit_hugepages = 0 > vm.nr_pdflush_threads = 0 > vm.numa_zonelist_order = default > vm.oom_dump_tasks = 1 > vm.oom_kill_allocating_task = 0 > vm.overcommit_kbytes = 0 > vm.overcommit_memory = 1 > vm.overcommit_ratio = 50 > vm.page-cluster = 3 > vm.panic_on_oom = 0 > vm.percpu_pagelist_fraction = 0 > vm.stat_interval = 1 > error: permission denied on key 'vm.stat_refresh' > vm.swappiness = 0 > vm.user_reserve_kbytes = 131072 > vm.vfs_cache_pressure = 200 > vm.watermark_scale_factor = 100 > vm.zone_reclaim_mode = 7 > > # free -m > total used free shared buffers cached > Mem: 96646 46330 50315 0 25529 1228 > -/+ buffers/cache: 19572 77073 > Swap: 0 0 0 > > (Yes, we don't have any swap configured) > > On this particular one we have 56 disks, using both XFS and EXT4. I attach full > netconsole log for 18/01/2017. You can see there that we run drop_caches > regularly as it helps to keep the machine alive. > > Since then we've also tried mounting filesystems with sync flag to avoid > writeback and it seems to have helped a lot (full day without stalls). > > -- > You are receiving this mail because: > You are the assignee for the bug. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
