What would you guess parity speed on this?

[opentoe]

Before having a couple drives blow up on me and ports go bad I finally received my final parity drive. I went for the Western Digital Enterprise Gold model. I do think the parity build is going a little slow, or could that be a placebo affect since I haven't had to do a parity in such a long time. Do you think the speed at 166MB/sec is a little slow? Anyway I do think that WD RED PRO drive is the same drive as WD Gold drive. WD is large enough to handle multiple skus for the same product, easy for them.

[itimpi]

That speed seems very reasonable.   I think a lot of people get significantly less than you are getting.   It is also worth noting that all other things being equal it is the slowest drive involved in the current point in the check that determines the speed you will be getting.

[ChatNoir]

That seems on par with what I see on my server :

[MAM59]

the gold drives alone can be a bit faster, I'm getting around 210MB/s.

 

But once I've added a WD-RED-Pro 10Tb, speed dropped below 150MB/s unless the scan passes the 10TB area.

 

(usually speed drops in the inner regions, but here you notice that it speeds up quite alot before it slows down again later on).

 

So, the current speed heavily depends on the slowest drive that is currently within scanning range.

 

That's normal and an average of 150MB/s is fine.

 

just be patient

Edited April 9, 2022 by Michael Meiszl

[opentoe]

6 hours ago, itimpi said:

That speed seems very reasonable.   I think a lot of people get significantly less than you are getting.   It is also worth noting that all other things being equal it is the slowest drive involved in the current point in the check that determines the speed you will be getting.

Thanks! I constantly forget I have a couple real old 4GB drives in the array. When I did a long diskspeed test a few weeks ago all the 4GB drives dipped right down, and I have 4 of them. My array would be much more snappier if I didn't have those 4GB drives. With 15 drives I'm up at %80! After this parity is complete I have 1 more 10TB drive to add. I certainly can't remove all 4 of the 4TB drives, but I'll probably ditch 2 of them and be around %78-%79. If I do some house cleaning, I can certainly regain some space back. That's the cost of me liking those high bitrate content.

Thanks

 

Oh, I forgot to ask, what is everyone's numbers on the first page of their disk settings?

 

Tunable - poll attribute: 1800

Tunable - enable NCQ: AUTO

Tunable - NR REQUESTS: 1024

Tunable - md_num_stripes: 4096

Tunable - md_queue_limit: 80

Tunable - md_sync_limit: 5

Tunable - md_write_method: reconstruct write

 

I tried running the tunables script again but it started pounding out errors fairly quickly. Too bad. That was a great utility that should have taken on more development or at least continue to make it work. I bet so many users out there could gain some speed from adjusting these settings but they really are obscure for most people.

 

 

Edited April 9, 2022 by opentoe

[itimpi]

1 hour ago, opentoe said:

Tunable - poll attribute: 1800

I normally change this to something like 300 to get 5 minutes rather than 30 minutes as the interval