Very slow data disk rebuild.

[3vang]

New to unraid. I'm swapping out a data disk and I am getting between 15-20 MB/sec speed. ETA of over 3 to 4 days. Seems like that's not normal.

Can someone help me figure out what is going on?

 

 

unraid-diagnostics-20200722-1541.zip

[reftek]

i'm no expert on rebuild times, but both your parity drives are 5400 rpms that impact rebuild speed. Have you precleared the new drive? What speeds did you get while preclearing it? 3 or 4 days for a 6TB drive seems quite long to be 

 

parity:

Model Family:     WDC HGST Ultrastar He10
Device Model:     WDC WD80EMAZ-00WJTA0

User Capacity:    8,001,563,222,016 bytes [8.00 TB]
Rotation Rate:    5400 rpm

 

Model Family:     WDC HGST Ultrastar He10
Device Model:     WDC WD80EMAZ-00WJTA0
User Capacity:    8,001,563,222,016 bytes [8.00 TB]
Rotation Rate:    5400 rpm

Edited July 22, 2020 by reftek

[3vang]

40 minutes ago, reftek said:

i'm no expert but on rebuild times, but both your parity drives are 5400 rpms that could be it. have you precleared the new drive? what speeds did you get while preclearing it? 3 or 4 days seems quite long to be honest

 

All disks are 5400 RPM, but there's no way that is the reason for 15 MB/s. I recently added those parity drives and average speed were 150 MB/s. I did not preclear as I'm new and am not even sure that that is. The 6TB rebuilding disk came from a Freenas server. Disk was wipe by Freenas before pulling and moving it to unraid.

[trurl]

2 hours ago, 3vang said:

I did not preclear as I'm new and am not even sure that that is.

Preclear is only for testing new disks or disks you think may have some problems. Unraid doesn't even need a clear disk for a rebuild.

 

Nothing obvious in your syslog. Are you seeing anything in the Errors column on Main?

 

Are you trying to read/write lots of data during rebuild? That would slow things down.

 

How are your disks connected? Are any disks showing SMART warnings on the Dashboard?

[3vang]

On 7/22/2020 at 8:39 PM, trurl said:

Preclear is only for testing new disks or disks you think may have some problems. Unraid doesn't even need a clear disk for a rebuild.

 

Nothing obvious in your syslog. Are you seeing anything in the Errors column on Main?

 

Are you trying to read/write lots of data during rebuild? That would slow things down.

 

How are your disks connected? Are any disks showing SMART warnings on the Dashboard?

No errors on Main. No VMs, Docker or IO activity at all. All disks are onboard SATA on a Supermicro X10SDV-TLN4F board, with 2 NVMe as cache. No SMART warnings.

 

Edited September 4, 2020 by 3vang

[DivideBy0]

3 minutes ago, 3vang said:

No errors on Main. No VMs, Docker or IO activity at all. All disks are onboard SATA on a Supermicro X10SDV-TLN4F board, with 2 NVMe as cache. No SMART warnings.

 

There is a warning on Disk 1.  Not green.  What is that?  Can you dig in?

 

[3vang]

Just now, johnwhicker said:

 

There is a warning on Disk 1.  Not green.  What is that?  Can you dig in?

 

"Device Contents Emulated Click to spin down device" That is the disk being rebuild. I am assuming that is normal status for the replaced disk that is currently rebuilding. 

[DivideBy0]

23 minutes ago, 3vang said:

"Device Contents Emulated Click to spin down device" That is the disk being rebuild. I am assuming that is normal status for the replaced disk that is currently rebuilding. 

 Yes if is being rebuild yes that correct.

[JorgeB]

WD60EZAZ it's SMR, and while they generally perform OK with Unraid when writting sequentially you might be hitting the SMR wall, if the rebuild starts fast and it slows down after a few minutes it's likely that.