How we test.... storage

Storage devices are often designed to work well in synthetic benchmark tests, and there can be no correlation between these results and real-world performance. For this reason, we use real-world file copies to test performance. We test how long it takes each product to read and write large and small files.

As file transfers always involve two storage devices, we use a 100MB RAM disk to copy the files from. This is extremely fast and ensures that any sluggish performance can be attributed to the storage device on test rather than the data source. Test results are graphed against the average performance of products that we’ve already tested.

Large files test

WHAT IT DOES: In our large files test we repeatedly copy a single 100MB file. We use a Visual Basic script to copy the file to and from the device. We calculate an average performance in megabytes per second for reads and writes, which are combined into an overall average MB/s figure.

Small files test

SETTINGS: Copy to/from 100MB RAM disk

WHAT IT DOES: In our small files test we repeatedly copy a folder containing several thousand files with a total size of 100MB. We use a Visual Basic script to copy the folder to and from the device. We calculate an average performance in megabytes per second for reads and writes, which are combined into an overall average MB/s figure.

Test bed

3.6GHz Intel Pentium 4 560
Intel i915 Motherboard
1GB DDR RAM

Reference scores

Hard disks
Large files: 60MB/s
Small files: 17MB/s

External hard disks
Large files 37MB/s
Small files 12MB/s

Flash drives
Large files 15MB/s
Small files 7MB/s