What kind of data does the disk test read/write?

The standard read test creates a file of 512MB, all other standard disk test create files 200MB in size. The file is filled with data that has a randomness of about 20% before the test begins. The randomness is seeded and is the same every time.

  • All reads and writes are done in 32kb blocks
  • Any data written once the tests commence is also roughly 20% random and seeded in the same manner.
  • If the drive has NTFS compression turned on, PerformanceTest will still try to use an uncompressed file for the standard tests. If it can't create a file in a uncomprssed state, the test will fail.