• Andrew Morton's avatar
    [PATCH] drop-pagecache · 9d0243bc
    Andrew Morton authored
    Add /proc/sys/vm/drop_caches.  When written to, this will cause the kernel to
    discard as much pagecache and/or reclaimable slab objects as it can.  THis
    operation requires root permissions.
    It won't drop dirty data, so the user should run `sync' first.
    a) Holds inode_lock for exorbitant amounts of time.
    b) Needs to be taught about NUMA nodes: propagate these all the way through
       so the discarding can be controlled on a per-node basis.
    This is a debugging feature: useful for getting consistent results between
    filesystem benchmarks.  We could possibly put it under a config option, but
    it's less than 300 bytes.
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
drop_caches.c 1.41 KB