3DMark Storage Benchmark score

The 3DMark Storage Benchmark produces an overall score, which is calculated from the bandwidth and average access time secondary metrics. The score is rounded to the nearest integer. The better the performance, the higher the score.

3DMark Storage score    =    geometric mean (bandwidth, 1 / average access time) 

Average access time

During a trace playback, the start and end time is measured for each I/O. 

access_time_for_an_I/O     =    end time - start time 

The filesystem can issue other types of I/O other than read and write, for example, create file and close file. To be able to focus on actual data transfer performance, we measure only the access times for read and write operations. 

average_access_time        =    arithmetic mean of only read and write access time 

Bandwidth

Busy time is a metric used to quantify the amount of time that the storage device is executing I/Os. It is defined as the sum of all times when at least one I/O was executing. Again, to be able to focus on data transfer performance, we define busy_time_for_read_and_write as the time when at least one read or write operation was executing. Using this and the number of bytes being transferred during the trace playback, we define: 

bandwidth                  =    bytes / busy_time_for_read_and_write