In the Database pattern the drive is processing a stream of requests to read and write 8KB random-address data blocks. The ratio of read to write requests is changing from 0% to 100% with a step of 10% throughout the test while the request queue depth varies from 1 to 256.
You can click the following link to view the tabled results for IOMeter: Database pattern.
We will build diagrams for request queue depths of 1, 16 and 256.
Western Digital’s products are excellent under the low load. The Caviar Black is absolutely unrivalled whereas the 1TB Caviar Green is second with its 5400rpm spindle rotation speed. The new 2TB Caviar Green is quite good, too. It is just a little slower than the Barracuda 7200.12 series model, the best of the Seagate team. The Barracuda 7200.11 series is quite poor again: the 1.5TB is just slower than the others while the 1TB model lacks deferred writing altogether.
The standings do not change much as the load grows up except that the 2TB Western Digital slows down somewhat and now competes with the 1.5TB Seagate. Well, that’s anyway a very good performance for a 5400rpm drive with highest-density platters.
We don’t see anything new here but it is interesting to see the new Caviar Green lagging behind the older one at any load. This indicates that the transition to higher-density platters has had a negative effect on the speed in relatively real-life tasks.
To sum up this part of our test session, we will show you diagrams with five queue depths for each of the three new products.
Well, Seagate has managed to bring the firmware back to a more or less good shape when the Barracuda 7200.11 is about to go away. We saw similar results (good request reordering, average-efficiency deferred writing) in the earliest models of this series. And now we see the same in the last, 1.5TB model.
Seagate’s hard disk firmware develops in strange ways. While the other manufacturers are increasing performance, the Seagate Barracuda 7200.12 has a lower efficiency of request reordering in comparison with the previous series. Is it the tradeoff for the lack of problems with random writing in small data blocks? But Western Digital is quite able to combine it with highly efficient firmware. So, Seagate developers have got a lot of work to do yet, and we hope they won’t make the same mistakes as in the previous series.
The largest-capacity drive from Western Digital behaves exactly like every other HDD from that brand.