Hello,

I have a primary/secondary node with 2 ressources.
When I watch the i/O performance i look some think like this :

When I watch the physical drive utilisation :

root@relax:~# iostat -x /dev/sda 1
Linux 2.6.32-5-amd64 (relax)     01/19/2012     _x86_64_    (16 CPU)

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.02    0.00    1.09    0.02    0.00   98.87

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util sda 220.78 700.91 555.52 374.88 20794.66 21227.05 45.16 1.54 1.66 0.42 38.87

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.04    0.00    0.17    0.00    0.00   99.79

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util sda 186.00 48.00 211.00 162.00 15392.00 2624.00 48.30 0.03 0.09 0.06 2.40

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.29    0.00    0.00   99.71

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util sda 197.00 9.00 379.00 117.00 19472.00 1172.00 41.62 0.15 0.31 0.19 9.60

When I watch the drbd device utilisation :

root@relax:~# iostat -x /dev/drbd0 1
Linux 2.6.32-5-amd64 (relax)     01/19/2012     _x86_64_    (16 CPU)

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.02    0.00    1.09    0.02    0.00   98.87

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util drbd0 0.00 0.00 775.16 1016.47 20729.96 21174.70 23.39 0.94 5.51 0.56 99.85

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.56    0.00    0.00   99.44

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util drbd0 0.00 0.00 426.00 104.00 15648.00 1262.00 31.91 5.19 0.15 1.87 99.20

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.56    0.00    0.00   99.44

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util drbd0 0.00 0.00 404.00 148.00 15888.00 1872.00 32.17 5.78 0.33 1.80 99.60

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.31    0.00    0.00   99.69

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util drbd0 0.00 0.00 398.00 117.00 15632.00 1736.00 33.72 5.28 0.10 1.94 100.00

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    0.24    0.00    0.00   99.76

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util drbd0 0.00 0.00 406.00 106.00 15376.00 1382.00 32.73 5.07 0.17 1.92 98.40

I don't understand why my drbd device is at 100 %util.

This is my ressource configuration : There are a raid 0 hardware with 12 sas 15k drives.

resource data {
  protocol C;

  startup {
    wfc-timeout 0;
  }

  disk {
    on-io-error detach;
  }

  syncer {
    rate 20M;
    verify-alg md5;
  }

  on surtax {
    device    /dev/drbd0;
    disk      /dev/sda;
    address   10.1.42.11:7788;
    meta-disk internal;
  }

  on relax {
    device    /dev/drbd0;
    disk      /dev/sda;
    address   10.1.42.12:7788;
    meta-disk internal;
  }
}

What's wrong on my configuration ?

Thank's

Matthieu

_______________________________________________
drbd-user mailing list
drbd-user@lists.linbit.com
http://lists.linbit.com/mailman/listinfo/drbd-user

Reply via email to