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Diffstat (limited to 'Documentation/vm/ksm.txt')
| -rw-r--r-- | Documentation/vm/ksm.txt | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/Documentation/vm/ksm.txt b/Documentation/vm/ksm.txt index 25cc89ba811b..f34a8ee6f860 100644 --- a/Documentation/vm/ksm.txt +++ b/Documentation/vm/ksm.txt @@ -60,10 +60,18 @@ sleep_millisecs - how many milliseconds ksmd should sleep before next scan merge_across_nodes - specifies if pages from different numa nodes can be merged. When set to 0, ksm merges only pages which physically - reside in the memory area of same NUMA node. It brings - lower latency to access to shared page. Value can be - changed only when there is no ksm shared pages in system. - Default: 1 + reside in the memory area of same NUMA node. That brings + lower latency to access of shared pages. Systems with more + nodes, at significant NUMA distances, are likely to benefit + from the lower latency of setting 0. Smaller systems, which + need to minimize memory usage, are likely to benefit from + the greater sharing of setting 1 (default). You may wish to + compare how your system performs under each setting, before + deciding on which to use. merge_across_nodes setting can be + changed only when there are no ksm shared pages in system: + set run 2 to unmerge pages first, then to 1 after changing + merge_across_nodes, to remerge according to the new setting. + Default: 1 (merging across nodes as in earlier releases) run - set 0 to stop ksmd from running but keep merged pages, set 1 to run ksmd e.g. "echo 1 > /sys/kernel/mm/ksm/run", |