Parity Rebuild - extremely slow write speeds (1.4 MB/s)

[Ethan McDonnell]

I was doing a parity swap procedure to replace my current 4TB parity drive with my new 8TB drive and then replace disk 1 with the 4TB.

 

It was running fine at 90-100 MB/s but has now fallen down to 1.4 MB/s and seems to be staying there, I can't seem to find a cause for this. All Dockers are stopped and the 1 VM I have is shutdown. I've attached diagnostics.

 

1 CPU core seems to pegged at 100%, I assume this is normal during a rebuild?

 

The log also seems to be taking a large amount of memory.

 

Any help is appreciated.

tower-diagnostics-20240228-2226.zip

[Ethan McDonnell]

EDIT: I guess I'm not doing an actaul parity swap procedure, I'm just building new parity onto a drive. I can't have more than 6 drives connected as I only have Unraid Basic

[itimpi]

The syslog in the diagnostics shows you are getting continual read errors on disk5 so not much point in continuing.    Not quite sure why although the way it started suggests you might have an issue with the power/SATA cabling or insufficient power reaching the drive.  
 

Are your sure your PSU is OK and capable of handling the load of all the drives simultaneously?

[Ethan McDonnell]

I've never had issues with the power delivery/PSU on parity operations before although it is possible it's going bad. I'm going to try reseating all SATA and power cables to the drives and restarting the Parity-Sync.

 

Will update if the issue returns.

[Ethan McDonnell]

Reseating SATA/Power Cables on all drives fixed the issue.

 

Thank you for the help.