• Mel Gorman's avatar
    Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo · 467c996c
    Mel Gorman authored
    
    
    This patch provides fragmentation avoidance statistics via /proc/pagetypeinfo.
     The information is collected only on request so there is no runtime overhead.
     The statistics are in three parts:
    
    The first part prints information on the size of blocks that pages are
    being grouped on and looks like
    
    Page block order: 10
    Pages per block:  1024
    
    The second part is a more detailed version of /proc/buddyinfo and looks like
    
    Free pages count per migrate type at order       0      1      2      3      4      5      6      7      8      9     10
    Node    0, zone      DMA, type    Unmovable      0      0      0      0      0      0      0      0      0      0      0
    Node    0, zone      DMA, type  Reclaimable      1      0      0      0      0      0      0      0      0      0      0
    Node    0, zone      DMA, type      Movable      0      0      0      0      0      0      0      0      0      0      0
    Node    0, zone      DMA, type      Reserve      0      4      4      0      0      0      0      1      0      1      0
    Node    0, zone   Normal, type    Unmovable    111      8      4      4      2      3      1      0      0      0      0
    Node    0, zone   Normal, type  Reclaimable    293     89      8      0      0      0      0      0      0      0      0
    Node    0, zone   Normal, type      Movable      1      6     13      9      7      6      3      0      0      0      0
    Node    0, zone   Normal, type      Reserve      0      0      0      0      0      0      0      0      0      0      4
    
    The third part looks like
    
    Number of blocks type     Unmovable  Reclaimable      Movable      Reserve
    Node 0, zone      DMA            0            1            2            1
    Node 0, zone   Normal            3           17           94            4
    
    To walk the zones within a node with interrupts disabled, walk_zones_in_node()
    is introduced and shared between /proc/buddyinfo, /proc/zoneinfo and
    /proc/pagetypeinfo to reduce code duplication.  It seems specific to what
    vmstat.c requires but could be broken out as a general utility function in
    mmzone.c if there were other other potential users.
    Signed-off-by: default avatarMel Gorman <mel@csn.ul.ie>
    Acked-by: default avatarAndy Whitcroft <apw@shadowen.org>
    Acked-by: default avatarChristoph Lameter <clameter@sgi.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    467c996c
vmstat.c 20 KB