lkml.org 
[lkml]   [2008]   [Jul]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: PERF: performance tests with the split LRU VM in -mm
    On Mon, 28 Jul 2008 17:17:28 -0700
    Andrew Morton <akpm@linux-foundation.org> wrote:

    > /*
    > - * Try to keep the active list 2/3 of the size of the cache. And
    > - * make sure that refill_inactive is given a decent number of pages.
    > - *
    > - * The "scan_active + 1" here is important. With pagecache-intensive
    > - * workloads the inactive list is huge, and `ratio' evaluates to zero
    > - * all the time. Which pins the active list memory. So we add one to

    If the active list is so small that nr_active_file >> priority always
    evaluates to 0, I suspect it won't hurt at all to keep it around.

    After all, we now only scan once the (incrementing) scan number reaches
    swap_cluster_max.

    > - * `scan_active' just to make sure that the kernel will slowly sift
    > - * through the active list.
    > + * Add one to `nr_to_scan' just to make sure that the kernel will
    > + * slowly sift through the active list.
    > */
    > - if (zone->nr_active >= 4*(zone->nr_inactive*2 + 1)) {
    > - /* Don't scan more than 4 times the inactive list scan size */
    > - scan_active = 4*scan_inactive;
    >
    > (there was some regrettable information loss there).
    >
    > Is the scenario which that fix addresses no longer possible?

    I believe it is possible, but harmless. Maybe even desired.

    > On a different topic, I am staring in frustration at
    > introduce-__get_user_pages.patch, which says:
    >
    > New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS.
    > because current get_user_pages() can't grab PROT_NONE pages theresore
    > it cause PROT_NONE pages can't munlock.
    >
    > could someone please work out for me which of these patches:
    >
    > vmscan-move-isolate_lru_page-to-vmscanc.patch
    > vmscan-use-an-indexed-array-for-lru-variables.patch
    > swap-use-an-array-for-the-lru-pagevecs.patch
    > vmscan-free-swap-space-on-swap-in-activation.patch
    > define-page_file_cache-function.patch
    > vmscan-split-lru-lists-into-anon-file-sets.patch
    > vmscan-second-chance-replacement-for-anonymous-pages.patch
    > vmscan-fix-pagecache-reclaim-referenced-bit-check.patch
    > vmscan-add-newly-swapped-in-pages-to-the-inactive-list.patch
    > more-aggressively-use-lumpy-reclaim.patch
    > pageflag-helpers-for-configed-out-flags.patch
    > unevictable-lru-infrastructure.patch
    > unevictable-lru-page-statistics.patch
    > ramfs-and-ram-disk-pages-are-unevictable.patch
    > shm_locked-pages-are-unevictable.patch
    > mlock-mlocked-pages-are-unevictable.patch
    > mlock-downgrade-mmap-sem-while-populating-mlocked-regions.patch
    > mmap-handle-mlocked-pages-during-map-remap-unmap.patch
    >
    > that patch fixes?

    I'll take a look later. Time to drive home and eat dinner :)

    --
    All Rights Reversed


    \
     
     \ /
      Last update: 2008-07-29 02:33    [W:0.028 / U:61.452 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site