Faster software RAID reconstruction
Sunday, July 23rd, 2006When creating or reconstructing a Linux software RAID there is a default reconstruction rate at which the RAID will be created. On RHEL the default max speed at which it will reconstruct the array is 10000 KB/sec. This setting can easily be adjusted for the impatient among us.
echo -n 500000 > /proc/sys/dev/raid/speed_limit_max
The above command will set the max reconstruction speed to 500000 KB/sec (which will essentially max out at the speed of your drives, usually in the 50MB/sec zone from my experience).
Bumping the value up will tax the disk subsystem more than the default but often it’s worth it to get that warm fuzzy of having a consistent RAID.