Storage Assessment Test

This test measures the performance of the disk under test by using Windows System Assessment Tool (WinSAT) to check that the I/O performance data meets the required metrics.

Test details

Associated requirements

Device.Storage.Hd.AtaProtocol.Performance Device.Storage.Hd.Sata.BasicFunction

See the device hardware requirements.


Windows 7 (x64) Windows 7 (x86) Windows 8 (x64) Windows 8 (x86) Windows 8.1 x64 Windows 8.1 x86

Expected run time

~120 minutes


Certification Reliability




Running the test

Before you run the test, complete the test setup as described in the test requirements: Hard Disk Drive Testing Prerequisites.


For troubleshooting information, see Troubleshooting Device.Storage Testing.

More information

The test runs against the disk that is under test by determining and using the physical drive number to perform the workload. The WinSAT workload is used to assess the disk by using the “disk” test for the block storage device built into the tool. It measures the following performance requirements for any visible storage space utilization up to 95%:

  • Disk Sequential 64K Byte Read

  • Disk Random 16K Byte Read

  • Disk Sequential 64K Byte Write

  • Average Read Time with Sequential Writes

  • Latency: 95th Percentile

  • Latency: Maximum

  • Average Read Time with Random Writes

At each of the steps: 0%, 30%, 60%, 90%, and 95%, the metrics above are tested to ensure that the disk meets the performance metrics specified.


The % of utilization value is % of "used space" seen through the Windows file system.


If you are testing any drive that requires media, or testing in system-mode on a computer that contains drives that require media, you must insert media into the drives. The media that is used must be formatted.

Command usage

Command optionDescription

StorAT.exe /diskid “[StorageDriveNumber]”

Runs the test.



For command-line help for this test binary, type /h.


Command syntax

Command optionDescription


The disk ID.

Example: /diskid 0


The times to run WinSAT in testing.

Example: /loop 1


Log file name

Default value: StorATTest.wtl

Example: /log mytestlog


File list







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