Random Read & Write Patterns
Now we’ll see the dependence between the drives’ performance in random read and write modes on the size of the data block size. We will only discuss the processing of small data blocks measured in operations per second. With large data blocks, the performance depends on the drive’s sequential speeds.
Reading small data chunks is far from interesting: the HDDs are ranked according to their response time. The lower the response time, the higher the performance is.
The HDDs behave in a similar way with larger data blocks, too. You can only see them differ at 2MB and larger blocks when the sequential speed becomes the decisive factor. As expected, the Seagate HDDs are in the lead then, the 7200.11 being somewhat faster than the LP.
The huge cache and quick heads ensure a solid advantage to the Western Digital RE4-GP. This HDD easily copes with writing small-size random-address data blocks. The other power-efficient HDDs go neck and neck, the 1.5TB Western Digital being somewhat better and the Samsung somewhat worse than the others.
When the data blocks get larger, the Western Digital RE4-GP loses its advantage and is overtaken by the Seagate 7200.11 that has a higher sequential write speed.