1. 29 11月, 2016 1 次提交
  2. 12 11月, 2016 2 次提交
  3. 11 11月, 2016 1 次提交
    • J
      blk-wbt: add general throttling mechanism · e34cbd30
      Jens Axboe 提交于
      We can hook this up to the block layer, to help throttle buffered
      writes.
      
      wbt registers a few trace points that can be used to track what is
      happening in the system:
      
      wbt_lat: 259:0: latency 2446318
      wbt_stat: 259:0: rmean=2446318, rmin=2446318, rmax=2446318, rsamples=1,
                     wmean=518866, wmin=15522, wmax=5330353, wsamples=57
      wbt_step: 259:0: step down: step=1, window=72727272, background=8, normal=16, max=32
      
      This shows a sync issue event (wbt_lat) that exceeded it's time. wbt_stat
      dumps the current read/write stats for that window, and wbt_step shows a
      step down event where we now scale back writes. Each trace includes the
      device, 259:0 in this case.
      Signed-off-by: NJens Axboe <axboe@fb.com>
      e34cbd30