The patch titled mm: swap-token: add a comment for priority aging has been added to the -mm tree. Its filename is mm-swap-token-add-a-comment-for-priority-aging.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: swap-token: add a comment for priority aging From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Docuemnt some swap token aging design decisions. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Acked-by: Rik van Riel <riel@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/thrash.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff -puN mm/thrash.c~mm-swap-token-add-a-comment-for-priority-aging mm/thrash.c --- a/mm/thrash.c~mm-swap-token-add-a-comment-for-priority-aging +++ a/mm/thrash.c @@ -67,6 +67,17 @@ void grab_swap_token(struct mm_struct *m if (!swap_token_mm) goto replace_token; + /* + * Usually, we don't need priority aging because long interval faults + * makes priority decrease quickly. But there is one exception. If the + * token owner task is sleeping, it never make long interval faults. + * Thus, we need a priority aging mechanism instead. The requirements + * of priority aging are + * 1) An aging interval is reasonable enough long. Too short aging + * interval makes quick swap token lost and decrease performance. + * 2) The swap token owner task have to get priority aging even if + * it's under sleep. + */ if ((global_faults - last_aging) > TOKEN_AGING_INTERVAL) { swap_token_mm->token_priority /= 2; last_aging = global_faults; _ Patches currently in -mm which might be from kosaki.motohiro@xxxxxxxxxxxxxx are vmscanmemcg-memcg-aware-swap-token.patch vmscanmemcg-memcg-aware-swap-token-fix.patch vmscanmemcg-memcg-aware-swap-token-fix-checkpatch-fixes.patch vmscan-implement-swap-token-trace.patch vmscan-implement-swap-token-priority-aging.patch memcg-add-documentation-for-the-memorynumastat-api.patch memcg-add-documentation-for-the-memorynumastat-api-fix.patch mm-increase-reclaim_distance-to-30.patch slab-use-numa_no_node.patch mm-swap-token-fix-dead-link.patch mm-swap-token-makes-global-variables-to-function-local.patch mm-swap-token-add-a-comment-for-priority-aging.patch cpusets-randomize-node-rotor-used-in-cpuset_mem_spread_node.patch cpusets-randomize-node-rotor-used-in-cpuset_mem_spread_node-fix-2.patch cpusets-randomize-node-rotor-used-in-cpuset_mem_spread_node-cpusets-initialize-spread-rotor-lazily.patch cpumask-convert-for_each_cpumask-with-for_each_cpu.patch cpumask-alloc_cpumask_var-use-numa_no_node.patch cpumask-add-cpumask_var_t-documentation.patch kexec-remove-kmsg_dump_kexec.patch kexec-remove-kmsg_dump_kexec-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html