Transfer From Cache to Array

[stevenxl]

Hey folks, 

 

I am transferring a file from my cache (https://www.micron.com/products/storage/ssd/client-ssd/2400-ssd - the 512GB version) to my array. 

 

The data transfer rate is seems very slow:

 

>   9,394,687,673 100%   13.77MB/s    0:10:50 (xfr#1, to-chk=0/2)

 

13.77MB/s seems slow. By contrast, the parity check was showing an average of 60MB/s:

 

> Duration: 1 day, 13 hours, 19 minutes, 49 seconds. Average speed: 59.5 MB/s

 

What could be wrong with my setup? I am transferring a large (10GB, roughly) file using `rsync` from my NVME SSD to my HDD arrays. Any thoughts? 

[JorgeB]

Try enabling turbo write, if still slow post diags during the transfer.

[stevenxl]

8 hours ago, JorgeB said:

Try enabling turbo write, if still slow post diags during the transfer.

Thank you for this piece of advice. Things did speed up significantly:

 

> 13,342,405,607 100%   21.66MB/s    0:09:47 (xfr#2, to-chk=0/3)

 

I'm attaching the logs here (taken during transfer) in case there is a way to get better performance. Something still seems off, but maybe this is my expectations being wrong? 

 

P.S. Given how much fun I am having with unRAID and how great you have all been at support, I am basically at the point of buying a license.

unraid-diagnostics-20240614-0939.zip

Edited June 14 by stevenxl
Forgot attachment.

[JorgeB]

No storage related errors, but I do see you are using USB, that is not recommended for array or pool devices for multiple reasons, one of them is that performance can be spotty.

[stevenxl]

On 6/14/2024 at 10:20 AM, JorgeB said:

No storage related errors, but I do see you are using USB, that is not recommended for array or pool devices for multiple reasons, one of them is that performance can be spotty.

I understand the concern regarding USB connection, but I was doing the parity check on that same setup and it was doing 60MB/s. What would explain a drop to 25MB/s? 

[JorgeB]

USB speed could have degraded.

[stevenxl]

On 6/16/2024 at 3:47 AM, JorgeB said:

USB speed could have degraded.

Hm... the parity check was ran less than 30 days ago. You think the USB speed would have degraded in that time? 

 

I think I'll try a cache -> disk transfer to see what happens when FUSE is by-passed. 

[JorgeB]

52 minutes ago, stevenxl said:

You think the USB speed would have degraded in that time? 

I meant a degraded link, that can happen at anytime, try rebooting or using a different USB cables, but I'm afraid I cannot really help troubleshooting USB enclosures, and they can be a lost cause.

[stevenxl]

23 hours ago, JorgeB said:

I meant a degraded link, that can happen at anytime, try rebooting or using a different USB cables, but I'm afraid I cannot really help troubleshooting USB enclosures, and they can be a lost cause.

That is fair. Thank you!