1. 04 Oct, 2009 2 commits
    • Jens Axboe's avatar
      Revert "Seperate read and write statistics of in_flight requests" · 0f78ab98
      Jens Axboe authored
      This reverts commit a9327cac.
      
      Corrado Zoccolo <czoccolo@gmail.com> reports:
      
      "with 2.6.32-rc1 I started getting the following strange output from
      "iostat -kx 2":
      Linux 2.6.31bisect (et2) 	04/10/2009 	_i686_	(2 CPU)
      
      avg-cpu:  %user   %nice %system %iowait  %steal   %idle
                10,70    0,00    3,16   15,75    0,00   70,38
      
      Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
      avgrq-sz avgqu-sz   await  svctm  %util
      sda              18,22     0,00    0,67    0,01    14,77     0,02
      43,94     0,01   10,53 39043915,03 2629219,87
      sdb              60,89     9,68   50,79    3,04  1724,43    50,52
      65,95     0,70   13,06 488437,47 2629219,87
      
      avg-cpu:  %user   %nice %system %iowait  %steal   %idle
                 2,72    0,00    0,74    0,00    0,00   96,53
      
      Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
      avgrq-sz avgqu-sz   await  svctm  %util
      sda               0,00     0,00    0,00    0,00     0,00     0,00
      0,00     0,00    0,00   0,00 100,00
      sdb               0,00     0,00    0,00    0,00     0,00     0,00
      0,00     0,00    0,00   0,00 100,00
      
      avg-cpu:  %user   %nice %system %iowait  %steal   %idle
                 6,68    0,00    0,99    0,00    0,00   92,33
      
      Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
      avgrq-sz avgqu-sz   await  svctm  %util
      sda               0,00     0,00    0,00    0,00     0,00     0,00
      0,00     0,00    0,00   0,00 100,00
      sdb               0,00     0,00    0,00    0,00     0,00     0,00
      0,00     0,00    0,00   0,00 100,00
      
      avg-cpu:  %user   %nice %system %iowait  %steal   %idle
                 4,40    0,00    0,73    1,47    0,00   93,40
      
      Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
      avgrq-sz avgqu-sz   await  svctm  %util
      sda               0,00     0,00    0,00    0,00     0,00     0,00
      0,00     0,00    0,00   0,00 100,00
      sdb               0,00     4,00    0,00    3,00     0,00    28,00
      18,67     0,06   19,50 333,33 100,00
      
      Global values for service time and utilization are garbage. For
      interval values, utilization is always 100%, and service time is
      higher than normal.
      
      I bisected it down to:
      [a9327cac
      
      ] Seperate read and write
      statistics of in_flight requests
      and verified that reverting just that commit indeed solves the issue
      on 2.6.32-rc1."
      
      So until this is debugged, revert the bad commit.
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      0f78ab98
    • Jens Axboe's avatar
      cfq-iosched: don't delay async queue if it hasn't dispatched at all · e00c54c3
      Jens Axboe authored
      
      
      We cannot delay for the first dispatch of the async queue if it
      hasn't dispatched at all, since that could present a local user
      DoS attack vector using an app that just did slow timed sync reads
      while filling memory.
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      e00c54c3
  2. 03 Oct, 2009 5 commits
  3. 02 Oct, 2009 1 commit
    • Jens Axboe's avatar
      cfq-iosched: add a knob for desktop interactiveness · 1d223515
      Jens Axboe authored
      
      
      This is basically identical to what Vivek Goyal posted, but combined
      into one and labelled 'desktop' instead of 'fairness'. The goal
      is to continue to improve on the latency side of things as it relates
      to interactiveness, keeping the questionable bits under this sysfs
      tunable so it would be easy for throughput-only people to turn off.
      
      Apart from adding the interactive sysfs knob, it also adds the
      behavioural change of allowing slice idling even if the hardware
      does tagged command queuing.
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      1d223515
  4. 01 Oct, 2009 32 commits