Multithreaded Read & Write Patterns
The multithreaded tests simulate a situation when there are one to four clients accessing the virtual disk at the same time, the request queue depth varying from 1 to 8. The clients’ address zones do not overlap. We’ll discuss diagrams for a request queue of 1 as the most illustrative ones. When the queue is 2 or more requests long, the speed doesn’t depend much on the number of applications. You can also click the following links for the full results:
The Seagate loses its lead in terms of sequential speed as soon as we add a second data thread. The WD Caviar Blue goes ahead then. Having the same firmware, the Caviar Black has lower results for some reason. Perhaps it is a negative effect from its Dual-Processor electronics? Whatever the reason, it is even slower than the Caviar Green. The latter is very good, staying in second place at multiple threads.
The Samsung is a disappointment. Such low performance as it provides used to be a characteristic feature of Seagate’s products, but Seagate has solved that problem by now. Now it is the second drive from Samsung that looks poor in this test (the first one was the 750GB model of the SpinPoint F1 series). We wouldn’t like this performance to be a typical trait of the whole series. And we have some hope because the 1-terabyte model was quite good at multithreaded reading.
But it is the Samsung that copes best with multithreaded writing. The WD Caviar Blue is competing with it at two threads, but the Samsung is the single leader when it comes to handling more data threads. The Seagate is not good here: its speed drops to the level of the WD Caviar Green at multiple threads although it has a 50% higher speed than the latter at one thread.