ATTO Disk Benchmark is perhaps one of the oldest benchmarks going and is definitely the main staple for manufacturer performance specifications. ATTO uses RAW or compressible data and, for our benchmarks, we use a set length of 256mb and test both the read and write performance of various transfer sizes ranging from 0.5 to 8192kb. Manufacturers prefer this method of testing as it deals with raw (compressible) data rather than random (includes incompressible data) which, although more realistic, results in lower performance results.
The 250GB capacity Samsung 840 provides performance of 558MB/s read and 254MB/s write which is very close to listed specifications of 540MB/s read and 250MB/s write. It is good to see that this SSD hits very high performance from as low as 4k transfer sizes which will contribute significantly to excellent start time and software application performance where small file execution is so important.
Crystal Disk Benchmark is used to measure read and write performance through sampling of raw (0/1 Fill/compressible) or random data which is, for the most part, incompressible. In the Samsung 840 SSD, performance results are very similar whether we test with compressible or incompressible data and, for this reason, results are displayed utilizing incompressible data.
Samsung’s performance is pretty much maintained as we start to test with highly incompressible data samples and the low 4k random write performance of 93MB/s is excellent.
Up until recently, AS SSD was the only benchmark created specifically for SSD testing and it uses incompressible data. AS SSD, for the most part, gives us the ‘worst case scenario’ in SSD transfer speeds because of its use of incompressible data and many enthusiasts like to AS SSD for their needs. Transfer speeds are displayed on the left with IOPS results on the right.
We decided to post our AS SSD results with the 840 as the boot drive as performance actually improved after a few days of use that included some very demanding performance benchmarks. Total IOPS on the right is a bit lower than specifications, as is normal with this benchmark software, however,very quick access times and an unexpectedly high Total Score look very encouraging. Our AS SSD Copy Bench is one of the highest pulled off to date with all three tests hitting SATA 3 speeds: