• Michael Rubin's avatar
    writeback: report dirty thresholds in /proc/vmstat · 79da826a
    Michael Rubin authored
    The kernel already exposes the user desired thresholds in /proc/sys/vm
    with dirty_background_ratio and background_ratio.  But the kernel may
    alter the number requested without giving the user any indication that is
    the case.
    
    Knowing the actual ratios the kernel is honoring can help app developers
    understand how their buffered IO will be sent to the disk.
    
            $ grep threshold /proc/vmstat
            nr_dirty_threshold 409111
            nr_dirty_background_threshold 818223
    Signed-off-by: default avatarMichael Rubin <mrubin@google.com>
    Cc: Wu Fengguang <fengguang.wu@intel.com>
    Cc: Dave Chinner <david@fromorbit.com>
    Cc: Jens Axboe <axboe@kernel.dk>
    Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
    Cc: Nick Piggin <nickpiggin@yahoo.com.au>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    79da826a
vmstat.c 29.2 KB