Web-Server, File-Server and Workstation Patterns
The drives are tested under loads typical of servers and workstations.
The names of the patterns are self-explanatory. The Workstation pattern is used with the full capacity of the drive as well as with a 32GB partition. The request queue is limited to 32 requests in the Workstation pattern.
The results are presented as performance ratings. For the File-Server and Web-Server patterns the performance rating is the average speed of the drive under every load. For the Workstation pattern we use the following formula:
Rating (Workstation) = Total I/O (queue=1)/1 + Total I/O (queue=2)/2 + Total I/O (queue=4)/4 + Total I/O (queue=8)/8 + Total I/O (queue=16)/16.
When there are only read requests to be processed, Seagate HDDs take the lead, the 5900rpm newcomer being but slightly slower than its 7200rpm predecessor. Western Digital’s drives are similar to each other. The WD RE4-GP heads this group at short queue depths due to its rather quick heads, but its performance does not grow up much along with the queue depth because it lacks NCQ. As a result, it is downright slower than its cousins at long queue depths. The Samsung is too weak in comparison with the other HDDs.
When there is even a small share of write requests to be processed, the Western Digital RE4-GP takes the lead thanks to its large cache. But it lacks NCQ and is far from brilliant at long queue depths where the Seagate 7200.11 is supreme. Interestingly, it is not the power-efficient model from Seagate but the 2TB Green model from WD that is competing with the leader here. The Samsung is the worst performer, again.
The Western Digital RE4-GP has the highest overall rating, according to our formula.
When the share of writes is increased more and the queue depth is reduced, the WD RE4-GP wins. Next goes the Seagate 7200.11 which is followed by the power-efficient model from the same maker.
Take note of the 1.5TB Western Digital Caviar Green. It suffers a sudden performance hit at the shortest queue depth. This is the same peculiarity in its behavior as we have seen in the Database pattern.
When the test zone is reduced to 32GB, the HDDs with higher spindle rotation speeds go ahead. For example, the Seagate LP is obviously better than the others but cannot catch up with its predecessor. The WD RE4-GP has the best results among the 5400rpm models, and the Samsung is again slower than the rest of the HDDs.
Summing up this part of our tests, we can say that the WD RE4-GP is very good but it will only show its best in a RAID array. The Seagate LP is going to be better as a single disk. The Samsung is slow under server loads. Hopefully, Samsung’s server-optimized models will be better in this respect.