There is a built-in disk performance checker in Windows called
winsat disk -drive g
winsat with Administrator privileges;
g is the
G: drive in this example)
Info on winsat disk on technet.microsoft.com/en-us/library/cc742157.aspx
C:\WINDOWS\system32>winsat disk -drive g
Windows System Assessment Tool
> Running: Feature Enumeration ''
> Run Time 00:00:00.00
> Running: Storage Assessment '-drive g -ran -read'
> Run Time 00:00:04.17
> Running: Storage Assessment '-drive g -seq -read'
> Run Time 00:00:08.64
> Running: Storage Assessment '-drive g -seq -write'
> Run Time 00:00:17.47
> Running: Storage Assessment '-drive g -flush -seq'
> Run Time 00:00:03.53
> Running: Storage Assessment '-drive g -flush -ran'
> Run Time 00:00:04.16
> Disk Random 16.0 Read 21.05 MB/s 6.0
> Disk Sequential 64.0 Read 38.29 MB/s 4.9
> Disk Sequential 64.0 Write 39.67 MB/s 4.9
> Average Read Time with Sequential Writes 1.324 ms 7.4
> Latency: 95th Percentile 2.585 ms 7.3
> Latency: Maximum 26.977 ms 7.9
> Average Read Time with Random Writes 1.299 ms 8.1
> Total Run Time 00:00:39.41
By default it doesn't test Random Write speed though, so you could check random 16.0 write with:
winsat disk -write -ran -drive c for example.