diff options
Diffstat (limited to 'Documentation/sysctl/vm.txt')
| -rw-r--r-- | Documentation/sysctl/vm.txt | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 2dc246af488..7cee90223d3 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -28,7 +28,7 @@ Currently, these files are in /proc/sys/vm: - block_dump - drop-caches - zone_reclaim_mode -- zone_reclaim_interval +- min_unmapped_ratio - panic_on_oom ============================================================== @@ -167,17 +167,18 @@ use of files and builds up large slab caches. However, the slab shrink operation is global, may take a long time and free slabs in all nodes of the system. -================================================================ +============================================================= -zone_reclaim_interval: +min_unmapped_ratio: -The time allowed for off node allocations after zone reclaim -has failed to reclaim enough pages to allow a local allocation. +This is available only on NUMA kernels. -Time is set in seconds and set by default to 30 seconds. +A percentage of the file backed pages in each zone. Zone reclaim will only +occur if more than this percentage of pages are file backed and unmapped. +This is to insure that a minimal amount of local pages is still available for +file I/O even if the node is overallocated. -Reduce the interval if undesired off node allocations occur. However, too -frequent scans will have a negative impact onoff node allocation performance. +The default is 1 percent. ============================================================= |