I’m syncoiding from my normal RAIDz2 to a backup mirror made of 2 disks. I looked at zpool iostat and I noticed that one of the disks consistently shows less than half the write IOPS of the other: capacity operations bandwidth pool alloc free read write read write ------------------------------------ ----- ----- ----- ----- ----- ----- storage-volume-backup 5.03T 11.3T 0 867 ...

I’m syncoiding from my normal RAIDz2 to a backup mirror made of 2 disks. I looked at zpool iostat and I noticed that one of the disks consistently shows less than half the write IOPS of the other:

                                        capacity     operations     bandwidth 
pool                                  alloc   free   read  write   read  write
------------------------------------  -----  -----  -----  -----  -----  -----
storage-volume-backup                 5.03T  11.3T      0    867      0   330M
  mirror-0                            5.03T  11.3T      0    867      0   330M
    wwn-0x5000c500e8736faf                -      -      0    212      0   164M
    wwn-0x5000c500e8737337                -      -      0    654      0   165M

This is also evident in iostat:

     f/s f_await  aqu-sz  %util Device
    0.00    0.00    3.48  46.2% sda
    0.00    0.00    8.10  99.7% sdb

The difference is also evident in the temperatures of the disks. The busier disk is 4 degrees warmer than the other. The disks are identical on paper and bought at the same time.

Is this behaviour expected?

  • @themoonisacheese@sh.itjust.worksEnglish
    2•2 months ago

    Oh wow congrats, I’m currently in the struggle of stretching an ab350m to accept a 4600G and failing.

    You’re right, you should hit PCIe 3 speeds and it’s weird, but the fact that the drives swap speeds depending on how they’re plugged in points to either drivers or the chipset.

    • lightrushOPEnglish
      1•2 months ago

      On paper it should support it. I’m assuming it’s the ASRock AB350M. With a certain BIOS version of course. What’s wrong with it?

      • @themoonisacheese@sh.itjust.worksEnglish
        2•2 months ago

        It’s a gigabyte ab350m gaming-3 rev 1.0. it boots grub fine but then crashes right after displaying “loading Linux 6.x”, CPU led flashes then dram led stays on, I have to turn it off with the PSU switch.

        Either it’s a rev 1.0 bug which is a thing on those motherboards, or the CPU (or igpu) is defective.

        https://superuser.com/questions/1854228/proxmox-doesnt-boot-after-cpu-change

        I’m currently waiting on support from both the seller and gigabyte but I don’t expect anything out of it, though I’m still yet to test it in a different motherboard.

        • lightrushOPEnglish
          1•2 months ago

          Iiinteresting. I’m on the larger AB350-Gaming 3 and it’s got REV: 1.0 printed on it. No problems with the 5950X so far. 🤐 Either sheer luck or there could have been updated units before they officially changed the rev marking.

          • @themoonisacheese@sh.itjust.worksEnglish
            1•1 month ago

            Sorry I 'ever saw this, that sucks.

            Turns out mine was broken too. I put the CPU in my gaming rig and it worked fine, so I bought a new motherboard and the problem is gone.