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QTS 5.0.x

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Creating an SSD Over-Provisioning Test

During an SSD over-provisioning test, SSD Profiling Tool first fills the SSDs with random data. It then tests the random write performance of the SSDs 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%, SSD Profiling Tool will test SSD write performance in 5 phases, with over-provisioning set to 0%, 5%, 10%, 15%, and 20%. If the random write performance of the disk is very low during any phase, SSD Profiling Tool will end the phase early and move to the next one.

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

    The Create SSD 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 SSD determines the optimum amount of over-provisioning for all SSDs of the same model and capacity. Selecting multiple SSDs 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 data on the selected disks will be deleted.

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



    Test data size

    SSD Profiling Tool writes the specified amount of test data to the SSD during each test phase. Decreasing the test data size decreases test time but gives less accurate results.

    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

    SSD 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 SSDs, the test may take more than 24 hours.


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

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

    A confirmation message appears.

  13. Click OK.

SSD Profiling Tool creates and starts running the test. The test appears as a background task in QTS.