Web-Server, Fileserver 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 process, the WD Caviar Black has no rivals (unless you consider its enterprise counterpart from the RE3 series). The two new drives from Seagate are contesting for second place. The 2TB model from WD loses in this test, being slower even than its 1TB predecessor.
The Barracuda 7200.12 model is ahead of the Barracuda 7200.11 one thanks to higher performance at low loads, but the WD Caviar Black is still unrivalled. Higher recording density cannot win this test.
The picture changes dramatically as there appear write requests. Second place now goes to the 1TB WD Caviar Green whereas it 2TB series mate has risen from last position to challenge the new drives from Seagate. The 1TB Seagate Barracuda 7200.11 suffers through the lack of deferred writing and loses to everyone else.
The Seagate Barracuda 7200.12 is third but by a narrowest margin. The 1.5TB 7200rpm Seagate gives way to the 2TB WD which has more efficient firmware.
A large number of write requests is combined with variegated load here. As a result, the two new products from Seagate contesting for second place push the 5400rpm drives from WD back. The 1TB Seagate Barracuda 7200.11 still suffers through the lack of deferred writing.
Still, the Barracuda 7200.12 series model is somewhat better than the best of the Barracuda 7200.11 series for workstation use. The leader Western Digital Caviar Black is far ahead of its opponents, though.
The picture is radically different when the test zone is limited to 32GB. No wonder as the drives are using a narrow strip of platters, just a few cylinders. In this case the rotation speed, number and density of the platters are the decisive factor. The speed of the heads is not important because they are moving within a very short distance. Therefore it always makes sense to dedicate a small part at the beginning of the disk for a system partition. Then you will have maximum sequential speeds and low response time if you use data from the other partitions less frequently. This is actually the reason why we test hard disk drives under this load.
So, the WD Caviar Black is unable to compete with the higher-density drives from Seagate due to the reasons explained above. Interestingly, the 4-platter Barracuda 7200.11 is faster than the 2-platter Barracuda 7200.12: the recording density of the latter is not so high on the outermost tracks but 32 gigabytes takes fewer cylinders on four than on two platters.
The 2TB Western Digital turns in a very modest performance. It could not outperform even its 1TB series mate. This HDD seems to be far from breaking any performance records. It offers a record-breaking capacity instead.