Some thoughts on the performance of SSD RAID 0 arrays

Incompressible Data Test

For this test, we set CrystalDiskMark to the default mode, which uses incompressible data.

In the sequential read test with incompressible data, the fastest performance was achieved with smaller stripe sizes, but even the slowest RAID 0 configuration more than doubled the performance achieved by a single drive. The performance with a stripe size of 4 kiB was 11% higher than using 128 kiB stripes. In the sequential write test, the performance was around the same for all stripe sizes, and about 283% higher than a single SSD.

Moving on to the random read test using 512 kiB blocks, the fastest stripe size was 8 kiB. The array provided between 74% and 88% more performance than a single SSD. In the random test with 512 kiB blocks, all stripe sizes resulted in the same performance level, which was about 324% higher than a single SSD.

In both the random read and write tests using 4 kiB blocks, there was no big advantage on using a RAID 0 array, no matter the stripe size.