Futuremark PCMark 7
The popular PCMark 7 contains an individual disk subsystem benchmark. It is not a synthetic test, but is based on real-life applications. This benchmark reproduces typical disk usage scenarios and measures how fast they are completed in popular applications. Moreover, the disk access commands are not executed as a steady uninterrupted flow, but in a more realistic manner – with certain pauses caused by the need to process the data. The benchmark generates an overall disk subsystem performance rating as well as speed readings in MB/s in individual usage scenarios. Note that the absolute speed in these scenarios is not too high because of the above mentioned pauses between individual input/output operations. In other words, PCMark 7 shows you the speed of the disk subsystem from the application’s point of view. Numbers like that show us not only the pure performance of an SSD, but mostly how big of a performance gain a certain SSD can guarantee in real life.
We ran PCMark 7 on “steady” SSDs, which is what they are going to be in actual computer systems most of the time. Their performance in this case is affected not only by their controller or flash memory speed but also by the efficiency of their internal algorithms that fight performance degradation.
The PCMark 7 results are indicative of what we've said above. The high write speed of the Agility 4 series doesn't help them much in typical usage scenarios. They fall behind their SandForce-based opponents with asynchronous memory.
Now let’s check out the individual tests to get a more detailed picture of what our SSDs are capable of under various types of operational load:
Irrespective of the particular trace, the Agility 4 disks remain the slowest. This serves to confirm the fact that the most important factor in synthetic benchmarks is the speed of reading 4 KB data blocks with a short requests queue. It is this factor that largely determines the performance of an SSD in typical usage scenarios. The high performance of the Agility 4 series at writing and with a long request queue can only show up in some special scenarios.