On Tue, Oct 28, 2014 at 05:12:29PM -0200, Carlos Carvalho wrote: > J. Bruce Fields (bfields@xxxxxxxxxxxx) wrote on Tue, Oct 28, 2014 at 12:24:50PM BRST: > > On Tue, Oct 28, 2014 at 12:14:28PM -0200, Carlos Carvalho wrote: > > > J. Bruce Fields (bfields@xxxxxxxxxxxx) wrote on Tue, Oct 14, 2014 at 05:42:45PM BRT: > > > > On Mon, Oct 13, 2014 at 08:50:27PM -0300, Carlos Carvalho wrote: > > > > > J. Bruce Fields (bfields@xxxxxxxxxxxx) wrote on Mon, Oct 13, 2014 at 10:58:40AM BRT: > > > > > Note the big xprt_alloc. slabinfo is found in the kernel tree at tools/vm. > > > > > Another way to see it: > > > > > > > > > > urquell# sort -n /sys/kernel/slab/kmalloc-2048/alloc_calls | tail -n 2 > > > > > 1519 nfsd4_create_session+0x24a/0x810 age=189221/25894524/71426273 pid=5372-5436 cpus=0-11,13-16,19-20 nodes=0-1 > > > > > 3380755 xprt_alloc+0x1e/0x190 age=5/27767270/71441075 pid=6-32599 cpus=0-31 nodes=0-1 > > > > > > > > Agreed that the xprt_alloc is suspicious, though I don't really > > > > understand these statistics. > > > > > > > > Since you have 4.1 clients, maybe this would be explained by a leak in > > > > the backchannel code. > > > > > > We've set clients to use 4.0 and it only made the problem worse; the growth in > > > unreclaimable memory was faster. > > > > > > > It could certainly still be worth testing 3.17 if possible. > > > > > > We tested it and it SEEMS the problem doesn't appear in 3.17.1; the SUnreclaim > > > value oscillates up and down as usual, instead of increasing monotonically. > > > However it didn't last long enough for us to get conclusive numbers because > > > after about 5-6h the machine fills the screen with "NMI watchdog CPU #... is > > > locked for more than 22s". > > > > Are the backtraces with those messages? > > First one, nfsd: > > Oct 22 18:37:12 urquell kernel: NMI watchdog: BUG: soft lockup - CPU#23 stuck for 23s! [nfsd:12603] > Oct 22 18:37:12 urquell kernel: Modules linked in: > Oct 22 18:37:12 urquell kernel: CPU: 23 PID: 12603 Comm: nfsd Not tainted 3.17.1-urquell-slabdebug #2 > Oct 22 18:37:12 urquell kernel: Hardware name: SGI.COM SGI MIS Server/S2600JF, BIOS SE5C600.86B.01.03.0002.062020121504 06/20/2012 > Oct 22 18:37:12 urquell kernel: task: ffff880fbb321000 ti: ffff880fbaf58000 task.ti: ffff880fbaf58000 > Oct 22 18:37:12 urquell kernel: RIP: 0010:[<ffffffff82511685>] [<ffffffff82511685>] _raw_spin_unlock_irqrestore+0x5/0x10 > Oct 22 18:37:12 urquell kernel: RSP: 0018:ffff880fbaf5bde0 EFLAGS: 00000296 > Oct 22 18:37:12 urquell kernel: RAX: ffffffff82841930 RBX: ffffffff820963db RCX: 0000000000000000 > Oct 22 18:37:12 urquell kernel: RDX: ffffffff82841948 RSI: 0000000000000296 RDI: ffffffff82841940 > Oct 22 18:37:12 urquell kernel: RBP: ffff880fd1ac52d0 R08: 0000000000000000 R09: 0000000000000000 > Oct 22 18:37:12 urquell kernel: R10: ffff880fd1ac5b28 R11: ffff880fff804780 R12: 00000000ffffffff > Oct 22 18:37:12 urquell kernel: R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > Oct 22 18:37:12 urquell kernel: FS: 0000000000000000(0000) GS:ffff880fffde0000(0000) knlGS:0000000000000000 > Oct 22 18:37:12 urquell kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > Oct 22 18:37:12 urquell kernel: CR2: 00007f22e0b01400 CR3: 000000000280e000 CR4: 00000000000407e0 > Oct 22 18:37:12 urquell kernel: Stack: > Oct 22 18:37:12 urquell kernel: ffffffff821dd282 ffff880fbaf5bde8 ffff880fbaf5bde8 ffff881ff785c6d8 > Oct 22 18:37:12 urquell kernel: ffff880fd1ac52d0 ffff881ff785c6d8 0000000000000020 ffffffff8285dac0 > Oct 22 18:37:12 urquell kernel: ffffffff821e3550 ffff880fbaf5be28 ffff880fbaf5be28 ffff881ff785c6d8 > Oct 22 18:37:12 urquell kernel: Call Trace: > Oct 22 18:37:12 urquell kernel: [<ffffffff821dd282>] ? __destroy_client+0xd2/0x130 > Oct 22 18:37:12 urquell kernel: [<ffffffff821e3550>] ? nfs4_state_shutdown_net+0x150/0x1e0 > Oct 22 18:37:12 urquell kernel: [<ffffffff821c1152>] ? nfsd_shutdown_net+0x32/0x60 > Oct 22 18:37:12 urquell kernel: [<ffffffff821c11da>] ? nfsd_last_thread+0x5a/0x90 > Oct 22 18:37:12 urquell kernel: [<ffffffff821c163b>] ? nfsd_destroy+0x4b/0x70 > Oct 22 18:37:12 urquell kernel: [<ffffffff821c17a4>] ? nfsd+0x144/0x170 > Oct 22 18:37:12 urquell kernel: [<ffffffff821c1660>] ? nfsd_destroy+0x70/0x70 > Oct 22 18:37:12 urquell kernel: [<ffffffff8207f38c>] ? kthread+0xbc/0xe0 > Oct 22 18:37:12 urquell kernel: [<ffffffff8207f2d0>] ? __kthread_parkme+0x70/0x70 > Oct 22 18:37:12 urquell kernel: [<ffffffff82511dac>] ? ret_from_fork+0x7c/0xb0 > Oct 22 18:37:12 urquell kernel: [<ffffffff8207f2d0>] ? __kthread_parkme+0x70/0x70 That means the server was shutting down. Is this some kind of cluster failover or were you shutting it down by hand? ... > Then reboot. Next NMI appeared next day: > > Oct 23 11:43:24 urquell kernel: NMI watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [kworker/u64:3:6414] > Oct 23 11:43:24 urquell kernel: Modules linked in: > Oct 23 11:43:24 urquell kernel: CPU: 5 PID: 6414 Comm: kworker/u64:3 Not tainted 3.17.1-urquell-slabdebug #2 > Oct 23 11:43:24 urquell kernel: Hardware name: SGI.COM SGI MIS Server/S2600JF, BIOS SE5C600.86B.01.03.0002.062020121504 06/20/2012 > Oct 23 11:43:24 urquell kernel: Workqueue: nfsd4 laundromat_main > Oct 23 11:43:24 urquell kernel: task: ffff881ff0d49800 ti: ffff8813f5a04000 task.ti: ffff8813f5a04000 > Oct 23 11:43:24 urquell kernel: RIP: 0010:[<ffffffff85245cc8>] [<ffffffff85245cc8>] _atomic_dec_and_lock+0x18/0x60 > Oct 23 11:43:24 urquell kernel: RSP: 0018:ffff8813f5a07d08 EFLAGS: 00000246 > Oct 23 11:43:24 urquell kernel: RAX: 0000000000000000 RBX: ffffffff85096290 RCX: 00000000ffffffff > Oct 23 11:43:24 urquell kernel: RDX: 0000000000000000 RSI: ffffffff850963db RDI: ffff8813f5a07cf8 > Oct 23 11:43:24 urquell kernel: RBP: ffffffff85096093 R08: 0000000000000000 R09: 0000000000000001 > Oct 23 11:43:24 urquell kernel: R10: 0000000000000001 R11: 0140000000000000 R12: 0000000000000000 > Oct 23 11:43:24 urquell kernel: R13: ffff880ff5c752d0 R14: ffffffff851bdaa0 R15: 0000000000000206 > Oct 23 11:43:24 urquell kernel: FS: 0000000000000000(0000) GS:ffff880fffca0000(0000) knlGS:0000000000000000 > Oct 23 11:43:24 urquell kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > Oct 23 11:43:24 urquell kernel: CR2: ffffffffff600400 CR3: 000000000580e000 CR4: 00000000000407e0 > Oct 23 11:43:24 urquell kernel: Stack: > Oct 23 11:43:24 urquell kernel: ffff881fee03dba0 ffffffff85096093 ffff8813f5a07cf8 ffffffff851dcf49 > Oct 23 11:43:24 urquell kernel: ffff881fee039950 ffff881fee0398d8 ffff8813f5a07d48 ffffffff851dd282 > Oct 23 11:43:24 urquell kernel: ffff8813f5a07d48 ffff8813f5a07d48 ffff8813f5a07db8 ffff881ff7fbbd98 > Oct 23 11:43:24 urquell kernel: Call Trace: > Oct 23 11:43:24 urquell kernel: [<ffffffff85096093>] ? __wake_up+0x43/0x70 > Oct 23 11:43:24 urquell kernel: [<ffffffff851dcf49>] ? nfs4_put_stid+0x29/0x100 > Oct 23 11:43:24 urquell kernel: [<ffffffff851dd282>] ? __destroy_client+0xd2/0x130 > Oct 23 11:43:24 urquell kernel: [<ffffffff851dd449>] ? laundromat_main+0x149/0x3f0 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507a6a4>] ? process_one_work+0x134/0x340 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507adb4>] ? worker_thread+0x114/0x460 > Oct 23 11:43:24 urquell kernel: [<ffffffff85095b5c>] ? __wake_up_common+0x4c/0x80 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507aca0>] ? init_pwq+0x160/0x160 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507f38c>] ? kthread+0xbc/0xe0 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507f2d0>] ? __kthread_parkme+0x70/0x70 > Oct 23 11:43:24 urquell kernel: [<ffffffff85511dac>] ? ret_from_fork+0x7c/0xb0 > Oct 23 11:43:24 urquell kernel: [<ffffffff8507f2d0>] ? __kthread_parkme+0x70/0x70 Hm. So maybe we forgot to drop cl_lock somewhere? --b. > > Oct 23 11:43:52 urquell kernel: NMI watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [kworker/u64:3:6414] > Oct 23 11:43:52 urquell kernel: Modules linked in: > Oct 23 11:43:52 urquell kernel: CPU: 5 PID: 6414 Comm: kworker/u64:3 Tainted: G L 3.17.1-urquell-slabdebug #2 > Oct 23 11:43:52 urquell kernel: Hardware name: SGI.COM SGI MIS Server/S2600JF, BIOS SE5C600.86B.01.03.0002.062020121504 06/20/2012 > Oct 23 11:43:52 urquell kernel: Workqueue: nfsd4 laundromat_main > Oct 23 11:43:52 urquell kernel: task: ffff881ff0d49800 ti: ffff8813f5a04000 task.ti: ffff8813f5a04000 > Oct 23 11:43:52 urquell kernel: RIP: 0010:[<ffffffff85511685>] [<ffffffff85511685>] _raw_spin_unlock_irqrestore+0x5/0x10 > Oct 23 11:43:52 urquell kernel: RSP: 0018:ffff8813f5a07d40 EFLAGS: 00000296 > Oct 23 11:43:52 urquell kernel: RAX: ffffffff85841930 RBX: ffffffff850963db RCX: 0000000000000000 > Oct 23 11:43:52 urquell kernel: RDX: ffffffff85841948 RSI: 0000000000000296 RDI: ffffffff85841940 > Oct 23 11:43:52 urquell kernel: RBP: ffff881fee0398d8 R08: 0000000000000000 R09: 0000000000000001 > Oct 23 11:43:52 urquell kernel: R10: 0000000000000001 R11: 0140000000000000 R12: ffff8813f5a07d48 > Oct 23 11:43:52 urquell kernel: R13: ffff8813f5a07d48 R14: 0000000000000000 R15: 0000000000000001 > Oct 23 11:43:52 urquell kernel: FS: 0000000000000000(0000) GS:ffff880fffca0000(0000) knlGS:0000000000000000 > Oct 23 11:43:52 urquell kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > Oct 23 11:43:52 urquell kernel: CR2: ffffffffff600400 CR3: 000000000580e000 CR4: 00000000000407e0 > Oct 23 11:43:52 urquell kernel: Stack: > Oct 23 11:43:52 urquell kernel: ffffffff851dd282 ffff8813f5a07d48 ffff8813f5a07d48 ffff8813f5a07db8 > Oct 23 11:43:52 urquell kernel: ffff881ff7fbbd98 ffff8813f5a07db8 ffff881ff7fbbeb0 000000005449058d > Oct 23 11:43:52 urquell kernel: ffffffff851dd449 0000000000000000 0000000000000000 0000000000000000 > Oct 23 11:43:52 urquell kernel: Call Trace: > Oct 23 11:43:52 urquell kernel: [<ffffffff851dd282>] ? __destroy_client+0xd2/0x130 > Oct 23 11:43:52 urquell kernel: [<ffffffff851dd449>] ? laundromat_main+0x149/0x3f0 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507a6a4>] ? process_one_work+0x134/0x340 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507adb4>] ? worker_thread+0x114/0x460 > Oct 23 11:43:52 urquell kernel: [<ffffffff85095b5c>] ? __wake_up_common+0x4c/0x80 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507aca0>] ? init_pwq+0x160/0x160 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507f38c>] ? kthread+0xbc/0xe0 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507f2d0>] ? __kthread_parkme+0x70/0x70 > Oct 23 11:43:52 urquell kernel: [<ffffffff85511dac>] ? ret_from_fork+0x7c/0xb0 > Oct 23 11:43:52 urquell kernel: [<ffffffff8507f2d0>] ? __kthread_parkme+0x70/0x70 > > And it repeats, always kworker at the same core. > > We then reverted to 3.14.21, since an uptime of ~5h (under load) is not viable > in this mission critical server. > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
