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QuTS hero 5.0.x

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Creating a Storage Pool Over-Provisioning Test

During a storage pool over-provisioning test, ZFS Pool Profiling Tool first fills the storage pool with random data. It then tests the random write performance of the storage pool over several test phases, each using a different amount of over-provisioning.

For example, if a test is created with a test range of 0-20% and a test interval of 5%, ZFS Pool Profiling Tool will test pool write performance in five phases, with over-provisioning set to 0%, 5%, 10%, 15%, and 20%. If the random write performance of a disk is very low during any phase, ZFS Pool Profiling Tool will end the phase early and move to the next one.

  1. Go to ZFS Pool Profiling Tool > Review.
  2. Click + Create Test.

    The Create ZFS Pool Test wizard opens.

  3. Click Next.
  4. Optional: Select an expansion unit from the Enclosure Unit list.

    You cannot select disks from multiple expansion units.

  5. Select one or more disks.

    Selecting a single disk determines the optimum amount of over-provisioning for all disks of the same model and capacity. Selecting multiple disks determines the optimum amount of over-provisioning for that specific combination of disks and RAID type. Testing multiple disks gives more accurate results, but takes significantly longer than testing a single disk.


    All selected disks must be of the same drive type (e.g., HDD, SSD).


    All data on the selected disks will be deleted.

  6. Select a RAID type.
  7. Click Next.
  8. Optional: Configure the test settings.



    Over-provisioning test range

    Specify the minimum and maximum amount of over-provisioning to test.

    Test interval

    Specify the over-provisioning increments to test.

    End a test phase early if consistent performance is too low

    ZFS Pool Profiling Tool will end a test phase after 5 minutes of testing if the random write speeds during the phase are lower than a system-defined threshold.


    Enabling this avoids wasting time testing disks when the specified amount of over-provisioning is producing no measurable benefits.

  9. Review the estimated time required.

    For multiple disks, the test may take more than 24 hours.


    If the estimated test time is too long, reduce the test range or test interval.

  10. Click Next.
  11. Verify the test information.
  12. Click Create.

    A confirmation message appears.

  13. Click OK.

ZFS Pool Profiling Tool creates and starts running the test. The test appears as a background task in QuTS hero.