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?

  • Decronym@lemmy.decronym.xyzBEnglish
    11·
    11 days ago

    Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:

    Fewer Letters More Letters
    NVMe Non-Volatile Memory Express interface for mass storage
    PCIe Peripheral Component Interconnect Express
    SATA Serial AT Attachment interface for mass storage
    SSD Solid State Drive mass storage
    ZFS Solaris/Linux filesystem focusing on data integrity

    5 acronyms in this thread; the most compressed thread commented on today has 7 acronyms.

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