Ubuntu
linux package

  1. Yakkety (16.10)
  2. Bug #1518457
  3. Comment #174

Comment 174 for bug 1518457

Revision history for this message
In , sgnn7 (sgnn7-linux-kernel-bugs) wrote :

Same problem here:
- No swap machine
- Wily (U15.10) - 4.2.0-19-generic #23-Ubuntu SMP Wed Nov 11 11:39:30 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
- 1GB RAM

- `meminfo` - Should have enough RAM to not swap though buffers do seem high

MemTotal: 1014932 kB
MemFree: 231296 kB
MemAvailable: 871180 kB
Buffers: 580684 kB
Cached: 47812 kB
SwapCached: 0 kB
Active: 547952 kB
Inactive: 164364 kB
Active(anon): 84280 kB
Inactive(anon): 4288 kB
Active(file): 463672 kB
Inactive(file): 160076 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 0 kB
SwapFree: 0 kB
Dirty: 224 kB
Writeback: 0 kB
AnonPages: 83800 kB
Mapped: 39688 kB
Shmem: 4768 kB
Slab: 48008 kB
SReclaimable: 31172 kB
SUnreclaim: 16836 kB
KernelStack: 1936 kB
PageTables: 3844 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 507464 kB
Committed_AS: 314640 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 13524 kB
VmallocChunk: 34359717628 kB
HardwareCorrupted: 0 kB
AnonHugePages: 49152 kB
CmaTotal: 0 kB
CmaFree: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 53248 kB
DirectMap2M: 1126400 kB

- kernel config: https://gist.github.com/sgnn7/cbb41ce21d3a927eca27

- strace shows nothing interesting

- `perf` report:
Samples: 12K of event 'cpu-clock', Event count (approx.): 3245250000
Overhead Command Shared Object Symbol
  19.34% kswapd0 [kernel.kallsyms] [k] shrink_lruvec
  17.04% kswapd0 [kernel.kallsyms] [k] mem_cgroup_iter
   8.60% kswapd0 [kernel.kallsyms] [k] mem_cgroup_zone_lruvec
   6.57% kswapd0 [kernel.kallsyms] [k] shrink_slab
   5.47% kswapd0 [kernel.kallsyms] [k] global_dirty_limits
   4.18% kswapd0 [kernel.kallsyms] [k] domain_dirty_limits
   3.71% kswapd0 [kernel.kallsyms] [k] mem_cgroup_get_lru_size
   3.59% kswapd0 [kernel.kallsyms] [k] super_cache_count
   3.27% kswapd0 [kernel.kallsyms] [k] get_lru_size
   3.26% kswapd0 [kernel.kallsyms] [k] throttle_vm_writeout
   2.20% kswapd0 [kernel.kallsyms] [k] css_next_descendant_pre
   2.15% kswapd0 [kernel.kallsyms] [k] blk_flush_plug_list
   1.96% kswapd0 [kernel.kallsyms] [k] shrink_zone
   1.73% kswapd0 [kernel.kallsyms] [k] _raw_spin_lock
   1.59% kswapd0 [kernel.kallsyms] [k] __list_lru_count_one.isra.2
   1.43% kswapd0 [kernel.kallsyms] [k] list_lru_count_one
   1.37% kswapd0 [kernel.kallsyms] [k] memcg_kmem_is_active
   1.27% kswapd0 [kernel.kallsyms] [k] __raw_callee_save___pv_queued_spin_unlock
...

I'm going to try gdb, changing swappiness, changing vm.min_free_kbytes, and reducing buffer limits in that order and report back but most likely I'll have one shot before the bug goes away for the next few days.