• SeongJae Park's avatar
    mm/damon: introduce DAMON-based LRU-lists Sorting · 40e983cc
    SeongJae Park authored
    Users can do data access-aware LRU-lists sorting using 'LRU_PRIO' and
    'LRU_DEPRIO' DAMOS actions.  However, finding best parameters including
    the hotness/coldness thresholds, CPU quota, and watermarks could be
    challenging for some users.  To make the scheme easy to be used without
    complex tuning for common situations, this commit implements a static
    kernel module called 'DAMON_LRU_SORT' using the 'LRU_PRIO' and
    'LRU_DEPRIO' DAMOS actions.
    
    It proactively sorts LRU-lists using DAMON with conservatively chosen
    default values of the parameters.  That is, the module under its default
    parameters will make no harm for common situations but provide some level
    of efficiency improvements for systems having clear hot/cold access
    pattern under a level of memory pressure while consuming only a limited
    small portion of CPU time.
    
    Link: https://lkml.kernel.org/r/20220613192301.8817-9-sj@kernel.orgSigned-off-by: default avatarSeongJae Park <sj@kernel.org>
    Cc: Jonathan Corbet <corbet@lwn.net>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    40e983cc
lru_sort.c 15.8 KB