Parity swap VERY slow (5MB/s)

[WEHA]

I had a data disk bad and even disabled so I replaced it.

I only have a larger disk available so it wants to do a parity swap, I get it can take while but I'm seeing 5 / 6MB/s... for 3TB

Can someone point out how to get the ball rolling faster because at this rate it will take more than 5 days.

Diag attached.

unneptunus-diagnostics-20240120-1510.zip

[Kilrah]

So you're now copying parity data onto that 6TB drive?

Looks like it's an SMR drive so... you're just going to have to be very patient. 

 

You might be able to gain some time by pausing the operation, waiting an hour or so then resuming, and repeating everytime it falls down to negligible speeds.

Edited January 20 by Kilrah

[WEHA]

2 hours ago, Kilrah said:

So you're now copying parity data onto that 6TB drive?

Looks like it's an SMR drive so... you're just going to have to be very patient. 

 

You might be able to gain some time by pausing the operation, waiting an hour or so then resuming, and repeating everytime it falls down to negligible speeds.

I mean ok it's an SMR drive, but this bad? Is this not a sequential write?

It was pretty much like this from the beginning but I can give that a try

[Kilrah]

Some SMR drives are able to recognise sequential writes and bypass the caching but not all do.

 

 

[WEHA]

15 hours ago, Kilrah said:

Some SMR drives are able to recognise sequential writes and bypass the caching but not all do.

 

 

I guess this was one of those disks, I put in a non-smr and it's going 120-150MB/s...

I knew SMR were no good but THIS bad... wow

[itimpi]

1 hour ago, WEHA said:

I guess this was one of those disks, I put in a non-smr and it's going 120-150MB/s...

I knew SMR were no good but THIS bad... wow

In my experience they are fine for array drives which are mainly storing media (after initial load), but you probably do not want a SMR drive as a parity drive.