Multi-Thread Read & Write Patterns
The multi-threaded tests simulate a situation when there are from one to four clients accessing the hard disk at the same time. The depth of the outgoing request queue is varied from 1 to 8. We’ll discuss diagrams for a request queue of 1 as most representative of real-life operation modes.
This is quite different from what we’ve seen in the previous tests. When reading a single thread with a request queue depth of 1 the Handy Drive takes second place, being only slower than the FireWire-interfaced HDD. The distribution of positions in this pattern is identical to the results of sequential reading of large data blocks. The Western Digital is superior when processing more than one data thread while the Fujitsu slows down under such load, even though not as heavily as the FireWire-interfaced drive does. As a result, the Fujitsu takes third place at four data threads.
It’s also interesting with multi-threaded writing: the WD Passport wins the single thread test but sinks to last place when there are more threads to be processed, and the HD-227FW takes the lead. The Fujitsu is the slowest of all at processing a single thread and only faster than the Passport in the other cases.