Issue

• A box that keeps stalling repeatedly, with many threads showing the following trace:

PID: 70840  TASK: ffff88bf9e730ae0  CPU: 128  COMMAND: "java"
 #0 [ffff8a00e1687e90] crash_nmi_callback at ffffffff8102d2c6
 #1 [ffff8a00e1687ea0] notifier_call_chain at ffffffff81513455
 #2 [ffff8a00e1687ee0] atomic_notifier_call_chain at ffffffff815134ba
 #3 [ffff8a00e1687ef0] notify_die at ffffffff8109cc1e
 #4 [ffff8a00e1687f20] do_nmi at ffffffff8151111b
 #5 [ffff8a00e1687f50] nmi at ffffffff815109e0
    [exception RIP: _spin_lock_irqsave+0x2f]
    RIP: ffffffff8151013f  RSP: ffff8881f7dcf7a8  RFLAGS: 00000093
    RAX: 0000000000002259  RBX: ffff88000002a598  RCX: 0000000000002256
    RDX: 0000000000000246  RSI: 0000000022592252  RDI: ffff88000002a598
    RBP: ffff8881f7dcf7a8   R8: ffffea00326d5000   R9: 0000000000000000
    R10: ffff88002c417f40  R11: 0000000000000000  R12: ffff8881f7dcf860
    R13: 0000000000e68600  R14: ffffea00326d5000  R15: 000000000016cda9
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
--- <NMI exception stack> ---
 #6 [ffff8881f7dcf7a8] _spin_lock_irqsave at ffffffff8151013f
 #7 [ffff8881f7dcf7b0] compact_checklock_irqsave at ffffffff811623e2
 #8 [ffff8881f7dcf7e0] compaction_alloc at ffffffff81162712
 #9 [ffff8881f7dcf8a0] migrate_pages at ffffffff8116d063
#10 [ffff8881f7dcf950] compact_zone at ffffffff811630a1
#11 [ffff8881f7dcfa10] compact_zone_order at ffffffff811636ac
#12 [ffff8881f7dcfac0] try_to_compact_pages at ffffffff811637e1
#13 [ffff8881f7dcfb30] __alloc_pages_direct_compact at ffffffff8112b9ca
#14 [ffff8881f7dcfba0] __alloc_pages_nodemask at ffffffff8112c02b
#15 [ffff8881f7dcfce0] alloc_pages_vma at ffffffff81160a5a
#16 [ffff8881f7dcfd30] do_huge_pmd_anonymous_page at ffffffff8117b5d5
#17 [ffff8881f7dcfd90] handle_mm_fault at ffffffff81144440
#18 [ffff8881f7dcfe00] __do_page_fault at ffffffff810474c9
#19 [ffff8881f7dcff20] do_page_fault at ffffffff8151339e
#20 [ffff8881f7dcff50] page_fault at ffffffff81510755
    RIP: 00007ff73855efb1  RSP: 00007ff71e975870  RFLAGS: 00010203
    RAX: 00007ff72fcf0000  RBX: 0000000000000011  RCX: 00007ff73855efad
    RDX: 0000000000000006  RSI: 00007ff72fcf0000  RDI: 00007ff7389708f0
    RBP: 00007ff71e975870   R8: 00007ff72f594d70   R9: 0000000000218e89
    R10: 00007ff738a49c20  R11: 0000000000000006  R12: 00007ff72fcf0000
    R13: 00007ff72f594d70  R14: 00000000415613e8  R15: 00000000415613e0
    ORIG_RAX: ffffffffffffffff  CS: 0033  SS: 002b

It appears that THP defragmentation is over-contending the LRU lock.