Parity Write stuck @ 50mb/s


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Hello,

 

I just added new drive to my array, 8TB HGST he8. 

Before adding the new drives to expand the array, I added 2 8TB drives for the Parity but the build speed is super slow.

My specs are i7 7700 12Gb Ram and an arrangement of RED + HGST He drives. Everything is plugged into the 6 SATA ports of my motherboard, no SAS card yet.

 

532276564_2019-05-1212_08_43-unRAID_Main.thumb.jpg.b5178a034b937b966d6595f8eb612bed.jpg

 

I tried the SDPARM command sdparm -g WCE /dev/sdf but I have a WCE not found error, maybe its because it's only for SAS drives?

Then I installed the Turbowrite plugin as suggested here 

but the speed is not changed at all, exactly the same.

 

1106821442_2019-05-1212_13_32-unRAID_Turbo.thumb.jpg.49c77187b9a8dd2595721e0ab1b79efd.jpg 

 

Is there anything I can do ?

 

Thanks

 

unraid-diagnostics-20190512-1032.zip

Edited by yendi
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I get that but none of the disk has a read/write speed of ~50mb.

The HGST where around 130mb/s (7200rpm) during the preclear, and the REDs average read/write are 100+

And I am talking about Parity initial build so it should be

read speed of all disk from array --> write speed of HGST (Parity)

I am not writing to the array like copying from my computer to the array...

Edited by yendi
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How far the parity rebuild?

 

10% means it is nearing the 1 TB border of disk2. At this point throughput of disk2 is already substantially lower than 110 Mb/s

20% means it is nearing the end of disk2. At this point performance of disk2 is at its lowest

 

>25% disk2 is not involved anymore and write speed should go up

 

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Ok I will leave it and see as it is only @ 2% (I cancelled it multiple times and ran some tests). I was thinking initially that there was something odd with the writing speed of the new drives in parity, not read speed.

I will update this post when I pass the 25% mark.

 

Total size:	8 TB	
Elapsed time:	1 hour, 6 minutes	
Current position:	203 GB (2.5 %)	
Estimated speed:	51.3 MB/sec	
Estimated finish:	1 day, 18 hours, 13 minutes

 

Thanks

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3 hours ago, ljm42 said:

@Squid is this something Fix Common Problems could detect?

Done.  Can't test this on my system, but the code should catch what's listed in the OP's diagnostics - follows the rules on the avoid spinups (if avoidance  is enabled, FCP won't run smartctl on the drive if its spundown).  Let me know if any false positives and/or missed.

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23 minutes ago, Squid said:

Done.  Can't test this on my system, but the code should catch what's listed in the OP's diagnostics - follows the rules on the avoid spinups (if avoidance  is enabled, FCP won't run smartctl on the drive if its spundown).  Let me know if any false positives and/or missed.

Very cool @Squid! FCP is awesome for this type of proactive notification

 

No false positives here.

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8 minutes ago, ljm42 said:

Very cool @Squid! FCP is awesome for this type of proactive notification

 

No false positives here.

I issued another quick update that should never have a false positive, (uses hdparm instead), and will catch (if it ever happens) that write-caching is disabled but smartctl doesn't show that fact.  That I could test :) 

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