Slow SSD performance withing Proxmox

[Mr.Goodcat]

Hi,

I'm facing slow linear SSD write performance within Proxmox 8.4.2.
That's outside a VM, i.e. directly moving files via proxmox commandline from one drive to another. My machine is using a Supermicro SAS/SATA backplane (without any expander), a Ryzen 2000 CPU series with ECC RAM and a plain IT HBA (i.e. no hardware RAID).
Oddly enough, a bog-standard consumer SSD (SanDisk Ultra 3D 2 TB, SATA) achieves ~140MBps on average (tested via rsync of >200GB, with most files greater than 1GB each), while my Micron 5200 ECO 3.84TB SSD (also tested with another Micron 5210, both SATA and less than 10h used) breaks down quickly to a paltry ~14MBps. The same is true regardless of backplane port, controller (onboard AMD vs. IBM M1015), ext4/ZFS and tool used for transfering files (rsync, dd, mv). Using Windows on a different computer yields over 200MBps sustained, even via a cheap USB to SATA adapter. Reboots didn't change performance in Proxmox either.

I know cheap consumer SSDs aren't recommended, but these drives aren't exactly bottom of the barrel. Does anyone have an idea what could be going on here? Thanks!

 

[Mr.Goodcat]

And what is your problem? this is normal für ssd.
With a nvme2 pcie 3 2 TB i got only 20 MBtye/s and
a nvme2 pcie 4 1 TB i get about 40 - 50 MBtye/s.
All have TLC Flash and DRam Write Cache.

This is decidedly not normal, otherwise the TLC SanDisk Ultra 3D 2 TB I also use would not attain much higher sustained write performance. Windows also does not show such poor performance metrics.