On Mon 09-01-17 23:02:10, Sami Farin wrote:
> # sysctl vm.vfs_cache_pressure=-100
>
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6640827866535449472
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6640827866535450112
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-661702561611775889
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6640827866535442432
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6562613194205300197
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6640827866535439872
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-659655090764208789
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6564660665198832072
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6562613194351275164
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6562615996648922728
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6564660665198832072
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-6562613194351264981
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-569296135781119076
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-565206492037048430
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-565212096665106188
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-569296135781119076
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-565206492037043196
> kernel: vmscan: shrink_slab: super_cache_scan+0x0/0x1a0 negative objects to
> delete nr=-659660388715270673
>
>
> Alternatively,
> # sysctl vm.vfs_cache_pressure=10000000
Both values are insane and admins do not do insane things to their
machines, do they?
I am not sure how much we want to check the input value. -100 is clearly
bogus and
.procname = "vfs_cache_pressure",
.data = &sysctl_vfs_cache_pressure,
.maxlen = sizeof(sysctl_vfs_cache_pressure),
.mode = 0644,
.proc_handler = &proc_dointvec,
.extra1 = &zero,
tries to enforce min (extra1) check except proc_dointvec doesn't care
about this... This is news to me. Only proc_dointvec_minmax does care
about extra*, it seems.
--
Michal Hocko
SUSE Labs
