FreeNAS running slow, high CPU & HDD usage and I have no idea why

[MrToddsFriends]

I giddily thought this was the case, the first time I scrubbed under 11, but nah, it's still atrociously slow

Just compared the scrub performances on my system for some rather recent FreeNAS versions, values shown for a mirror of two WD Red 3TB disks:

Code:

 FreeNAS Version | Scrub Rate
-----------------|------------
 9.10.2-U5	   | 35.1 MiB/s
 11.0-U4		 | 72.3 MiB/s
 11.1-U4		 | 88.2 MiB/s

Of course overall scrub rates as well as measurable and perceptible improvements will depend on fragmentation as well as other factors (disk configuration, ...).

Edit: "overall scrub rates" as well as "measurable" added to comment.

 

[diskdiddler]

That does seem to be an improvement, but perhaps it scales with spare CPU time? I know mine (I thought) had improved, but it still exceeds 24 hours unfortunately.

None the less, in the next 18 months, when money (and technology) allows, I should be getting a much better machine

 

[MrToddsFriends]

That does seem to be an improvement, but perhaps it scales with spare CPU time? I know mine (I thought) had improved, but it still exceeds 24 hours unfortunately.

I should have added that spare CPU time is/was always comparable and mostly irrelevant for the scrub performance numbers I showed. Each and every scrub (I'm letting run two such scrub jobs simultaneously) effectively causes a system load <= 1.0 per job while there are 8 CPU cores in my system (relatively slow ones, Intel Avoton C2750).