diff options
Diffstat (limited to 'Documentation/sysctl/vm.txt')
| -rw-r--r-- | Documentation/sysctl/vm.txt | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 9baf66a9ef4e..b920423f88cb 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -58,6 +58,7 @@ Currently, these files are in /proc/sys/vm: - percpu_pagelist_fraction - stat_interval - stat_refresh +- numa_stat - swappiness - user_reserve_kbytes - vfs_cache_pressure @@ -157,6 +158,10 @@ Note: the minimum value allowed for dirty_bytes is two pages (in bytes); any value lower than this limit will be ignored and the old configuration will be retained. +Note: the value of dirty_bytes also must be set greater than +dirty_background_bytes or the amount of memory corresponding to +dirty_background_ratio. + ============================================================== dirty_expire_centisecs @@ -176,6 +181,9 @@ generating disk writes will itself start writing out dirty data. The total available memory is not equal to total system memory. +Note: dirty_ratio must be set greater than dirty_background_ratio or +ratio corresponding to dirty_background_bytes. + ============================================================== dirty_writeback_centisecs @@ -622,7 +630,7 @@ oom_dump_tasks Enables a system-wide task dump (excluding kernel threads) to be produced when the kernel performs an OOM-killing and includes such information as -pid, uid, tgid, vm size, rss, nr_ptes, nr_pmds, swapents, oom_score_adj +pid, uid, tgid, vm size, rss, pgtables_bytes, swapents, oom_score_adj score, and name. This is helpful to determine why the OOM killer was invoked, to identify the rogue task that caused it, and to determine why the OOM killer chose the task it did to kill. @@ -792,10 +800,25 @@ with no ill effects: errors and warnings on these stats are suppressed.) ============================================================== +numa_stat + +This interface allows runtime configuration of numa statistics. + +When page allocation performance becomes a bottleneck and you can tolerate +some possible tool breakage and decreased numa counter precision, you can +do: + echo 0 > /proc/sys/vm/numa_stat + +When page allocation performance is not a bottleneck and you want all +tooling to work, you can do: + echo 1 > /proc/sys/vm/numa_stat + +============================================================== + swappiness This control is used to define how aggressive the kernel will swap -memory pages. Higher values will increase agressiveness, lower values +memory pages. Higher values will increase aggressiveness, lower values decrease the amount of swap. A value of 0 instructs the kernel not to initiate swap until the amount of free and file-backed pages is less than the high water mark in a zone. |