Strange SMB performance

[Jussi]

After changing all three disks in my RAIDZ1 pool (was running 12.0-U8), SMB performance dropped. Write speed was steady 105 MB/s and after the change around 50 MB/s. SMB client is a normal Window 10 Pro PC with Intel i5-7400T. Truenas now upgraded to 13.1, did not help.

Strange things:
- I have one jail running in the background with constant writing to another pool
- If the pool is not running, write speed to the SMB share is 113 MB/s
- When I stop writing in the jail, speed goes up to 113 MB/s after 1 minute 49 seconds
- With another PC (Windows 11, Intel i7-9700F) write speed to the SMB share is 105 MB/s with the jail running and 113 MB/s with the jail stopped

How to get the normal SMB performance back?

My Truenas server: Intel Xeon CPU E5507, 20 GB ECC memory, problematic SMB share pool with 3 pieces of Seagate Barracuda ST8000DM004, 3.5", 8000 GB, 5400 RPM.

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[LarsR]

The drives you have are SMR drives which do not work well with zfs. Only option to improve the performance would be to exchange the drives for known CMR drives like seagate ironwolf, ironwolf pro, exos or WD Red Pro drives.

 

[Jussi]

The drives you have are SMR drives which do not work well with zfs. Only option to improve the performance would be to exchange the drives for known CMR drives like seagate ironwolf, ironwolf pro, exos or WD Red Pro drives.

Why is the performance ok with the other Windows 11 PC? Earlier drives were Western Digital WD60EZAZ 6TB blue. I guess they were equally bad and still worked fine.