limit or pause resync of mdadm

If you have a running resync job of mdadm this job can impact your normal operations a lot under different circumstances. You can limit the resync throughput with two kernel variables:

  • /proc/sys/dev/raid/speed_limit_min
  • /proc/sys/dev/raid/speed_limit_max

You can set here the minimum and maximum bandwidth in kibibytes per second(1024 Bytes).

Unfortunately you cannot set 0 to pause the resync. But you can set it to 1 kibibyte per seconds. This is nearly zero and is enough to be nearly pause.

But pay attention! If you raid is not sync you risk data loss.