5

Once a month I've been doing 

echo check > /sys/block/md2/md/sync_action

in order to force a software raid consistency check. The problem is this is a 7.2T RAID 5. The consistency check takes days to complete and while it's running, everything on my system slows to a crawl. Is there any way to nice this (say by temporarily setting /proc/sys/dev/raid/speed_limit_max to something smaller for the duration of the check?

In general it pains me that even in the 4.13 linux kernel, extended disk I/O causes the system to grind to a halt; should be a solved problem by now.

pgoetz
  • 193

1 Answers1

2

What "resolved" it for me was to update these sysctl configs:

dev.raid.speed_limit_max = 25000
dev.raid.speed_limit_min = 1000

It takes much longer to run, but at least it doesn't slow down everything.

Only needed in HDD servers.
SSD and NVMe are fine with the defaults.

Nuno
  • 932