• KAMEZAWA Hiroyuki's avatar
    mm: count swap usage · b084d435
    KAMEZAWA Hiroyuki authored
    A frequent questions from users about memory management is what numbers of
    swap ents are user for processes.  And this information will give some
    hints to oom-killer.
    
    Besides we can count the number of swapents per a process by scanning
    /proc/<pid>/smaps, this is very slow and not good for usual process
    information handler which works like 'ps' or 'top'.  (ps or top is now
    enough slow..)
    
    This patch adds a counter of swapents to mm_counter and update is at each
    swap events.  Information is exported via /proc/<pid>/status file as
    
    [kamezawa@bluextal memory]$ cat /proc/self/status
    Name:   cat
    State:  R (running)
    Tgid:   2910
    Pid:    2910
    PPid:   2823
    TracerPid:      0
    Uid:    500     500     500     500
    Gid:    500     500     500     500
    FDSize: 256
    Groups: 500
    VmPeak:    82696 kB
    VmSize:    82696 kB
    VmLck:         0 kB
    VmHWM:       432 kB
    VmRSS:       432 kB
    VmData:      172 kB
    VmStk:        84 kB
    VmExe:        48 kB
    VmLib:      1568 kB
    VmPTE:        40 kB
    VmSwap:        0 kB <=============== this.
    
    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Reviewed-by: default avatarMinchan Kim <minchan.kim@gmail.com>
    Reviewed-by: default avatarChristoph Lameter <cl@linux-foundation.org>
    Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
    Cc: David Rientjes <rientjes@google.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    b084d435
task_mmu.c 21.2 KB