September 11, 20232 yr I reformatted my system cache drive to zfs, and added a disk to the array for zfs snapshot replication. Most of my array drives (including the new zfs drive) are 4TB, and typical read speeds for parity check start around 140-150MB/s and head down to ~80MB/s toward the end of the 4TB space on the array After backing up my cache drive to the array, restoring it back to the cache, and adding the new drive, I decided to kick off a parity check (there were some issues with mover hanging on the docker folders of the cache drive) Read speeds around the 1TB mark for the parity check are already down to ~33-40MB/s What would cause such a slow parity check after adding a new drive? Does having a mix of xfs and zfs drives affect parity check performance? Edited September 11, 20232 yr by veri745 typos
September 11, 20232 yr Community Expert 2 hours ago, veri745 said: What would cause such a slow parity check after adding a new drive? Does having a mix of xfs and zfs drives affect parity check performance? In theory it should not make any difference, but is ZFS housekeeping accesses drives then that could slow down the parity check.
September 12, 20232 yr Author Whatever it was causing the slow parity check did not persist the second night of the parity check (I have it set to pause during the day and resume at night), so I didn't get a chance to grab the diagnostics in the midst of the issue. Going to chalk it up to one of my docker containers doing some sort of media scan, since I had to blow away the docker system directory and re-create all the containers (although my appdata was all intact after the cache drive migration). I dunno. Edited September 12, 20232 yr by veri745
September 30, 20232 yr I transitioned all array disks to ZFS and am seeing parity check crawling along at 28MB/sec. Previously with XFS it was over 100 MB/sec with 10TB parity. Stopped docker services - no change to parity speed. Started docker services - docker tab showed as not running, no start stop would make a difference. Reboot Partity sync restarted and back to over 100 MB/sec. Docker containers all running fine. strange. diagnostics-20231001-0055.zip
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