I have recently built a new unraid server with 24 drives.  I am copying a bunch of data off my older synology to the unraid host and currently have parity turned off (due to the TB of data being copied). Also, I will be moving the larger drives off of the synology into the unraid host to slowly start expanding (88TB isn't enough compared to some of the servers here )

 

I can't for the life of me figure out why every drive is being read while writing to one drive.  I have no dockers, no cache at the moment and no vm's.  I have attached the diag zip in hopes that someone smarter than me in unraid can help me figure out what the issue is. 

 

I have looked online and through the forums to find something similar but have not.

 

Thank you all in advance for any assistance.

tower-diagnostics-20221014-2004.zip

6 hours ago, LordMael said:

I can't for the life of me figure out why every drive is being read while writing to one drive.

I would guess that's because turbo write is activated.

So that was part of the issue.  Because I also had 2 parity disks selected but not enabled that was the other part of the problem  I have unassigned the 2 parity disks (that weren't being used yet) and copy jobs are working much better.  Once everything is copied over, I'll turn parity back on and let that sync.

 

Thank you for pointing me in the right direction.

4 hours ago, LordMael said:

Because I also had 2 parity disks selected but not enabled that was the other part of the problem

Not sure I understand this part?   If parity disks are selected then they are being used?

On 10/15/2022 at 11:42 PM, itimpi said:

Not sure I understand this part?   If parity disks are selected then they are being used?

I had 2 drives assigned to be parity but no parity task had yet been started.  after shutting down the array, de-selecting the two parity drives and removing them from the parity assignment, copy was 2x as fast.  I have since finished copying over the 18TB of data from my old synology to my new unraid host and moved over the newer drives that were in the synology into the unraid host.  Went from 88TB to 108 TB with a 10TB parity drive.  I have a few drives i need to replace (the server came with used drives in it from work) so I will be ordering new drives to replace the ones that are showing errors.  

 

I hope this answers your question d[^_^]b

1 hour ago, LordMael said:

I had 2 drives assigned to be parity but no parity task had yet been started.

I don’t understand this statement    There is no parity task to start!    Parity in Unraid is real-time as writes happen and the only way to avoid updating parity during writes is to not have parity disks assigned.

You can have parity disks assigned and the parity task stopped.  This was a brand new array and I'm new to unraid so I thought by disabling the parity sync the copy would go faster, it doesn't. the only way it was moving faster was to shutdown the array, remove the drives that were assigned to the parity slots and then fire the array back up again.  i went from 50MB/s to 116MB/s writes.

 

Currently the array is building the parity on the 1x 10TB parity drive now that the data is all moved.

He means the parity drives were assigned but the sync canceled, and yes, that's no good for performance, they must be unassigned.