RND4K Q1T1 – Ignore, SQL Server doesn’t work like this.This is somewhat akin to an active OLTP server, or a TempDB drive. RND4K Q32T16 – random tiny operations, but many done at a time.SEQ1M Q1T1 – ignore, SQL Server doesn’t work like this.

For SQL Server, this is somewhat akin to doing backups or doing table scans of perfectly defragmented data, like a data warehouse. SEQ1M Q8T1 – lots of long, sequential operations.While it runs, here’s an explanation of each row’s results: You want to test where your data, log, and TempDB files live, and for fun, also test the C drive and your desktop or laptop for comparison.Īfter making your choices, click the All button. Keep an eye on the free space there – you don’t want to create a test file that can run your server out of drive space. Just know that the bigger the test file, the longer it takes to generate. Smaller test file sizes may look fast but don’t really reflect how a large database will work. If you’re under the gun, do a quick 1GiB test, but for real go-live prep, I like using 32GB to reduce the chances that I’m just hitting cache and getting artificially fast numbers. If you want a fast seat-of-the-pants guess, do 1, but keep in mind it can be wildly variant between passes if something else happens to be going on in the SAN. 1 – the number of test passes you want to run.The zip version can be just saved to a network share, and then anybody can run it from there.Īfter extracting the zip file’s contents, run DiskMark64.exe on an idle server or desktop first (not your live SQL Server, because it’ll slow things down while it runs.) It’ll look like this:Īcross the top, set the first three dropdowns to: The zip version doesn’t require an installer, which is cool because I’m not a fan of installing things on production servers. There are multiple download links – you want CRYSTALDISKMARK, not CrystalDiskInfo, and you want the Standard Edition, Zip Version. Go to the CrystalDiskMark download page, but PAY CLOSE ATTENTION. (I’ll be charitable and not tell you which one.) Instead, let’s get seat-of-the-pants numbers for your storage. It takes knowledge and time, and you only have one of those. I’ve written about how to test your SAN’s performance with SQLIO, but I’ll be honest with you: that’s the hard way.

How to read crystaldiskinfo results