Note: Customers are  encouraged to use Diskspd, a new and robust tool for testing their storage solutions instead of SQLIO tool.



The SQLIO Disk Subsystem Benchmark Tool is a tool provided by Microsoft (SQLIO from Microsoft Download), which can be used to determine the I/O capacity of a given configuration. However, it comes with the disclaimer that SQLIO is provided ‘as is’ and there is no support offered for any problems encountered when using the tool. Please refer to the EULA.doc for the license agreement prior to using this tool.

Tips on how to prevent or resolve issues when running the SQLIO tool, especially on Windows 7 and Windows Server 2008 R2:

  1. Ensure that you have created an exception for SQLIO in Data Execution Prevention (DEP). In Windows 7 or Windows Server 2008 R2, you can create exceptions in DEP by opening System Properties (sysdm.cpl) and then clicking Advanced. Then, in Performance, click Settings. Click Data Execution Prevention. If Turn on DEP for all programs and services except those I select is selected, click Add, then type the full path to SQLIO.EXE, including SQLIO.EXE. For example, C:\Program Files (x86)\SQLIO\SQLIO.EXE. If the other option, Turn on DEP for essential Windows programs and services only is selected, you do not need create an exception .

  2. If your SQLIO commands contain -fsequential and SQLIO is crashing, ensure you define a params.txt file that sets the test file size before testing.
  3. Ensure that all programs that are operating or could operate on the target drive for testing are off or suspended during the test. Two common examples include:
    1. Ensure that you configure exceptions in any virus scanning software that you have running or that could run during your test for both SQLIO.EXE and the target volume of the test.
    2. Ensure that you disable any drive indexing software. 

 To learn more about SQLIO, see the following related references: