Atto Disk Benchmark
The Atto Disk Benchmark reads and writes data blocks of different sizes as quickly as possible to random places on the SSD. We used the 4kB and 1MB tests. The 4kB tests reflect working with very small files, resembling what happens when starting up software. The 1MB test are a best-case scenario for SSDs and indicate what type of performance you can expect when working with large files, such as copying digital photos, MP3s, and films.
Four commands are simultaneously sent to the disks each time. Since the flash chips in SSDs are parallel controlled, smart controllers can execute multiple commands at once. This improves the performance. In real-life, Windows and other software will also simultaneously send multiple commands to the drives.
Please note: Atto Disk Benchmark uses compressible data. Many files - especially programme files - are like this. However, files such as digital photos, MP3s, or films are barely compressible or not compressible at all. The AS SSD benchmark on the next page provides a clearer picture.
Reading four 4kB data blocks at the same time doesn't go particularly fast on the new SSDs. However, the new Vertex 4 writes 4k data blocks faster than previously tested SSDs. Reading large data blocks (1MB) reaches 525MB/s, almost the maximum speed of a Serial ATA 600 bus. The 512GB version writes at 463MB/s and the 256GB version writes at 371MB/s. The SandForce SSDs generally score higher in this benchmark, but that is because Atto uses compressible data.