OCZ Z-Drive m84 PCI-Express SSD Review
Iometer Workstation and Database Results
As we noted in a previous SSD round-up article, though IOMeter is clearly thought of as a well respected industry standard drive benchmark, we're not completely comfortable with it for testing SSDs, as well as comparing their performance to standard hard drives. The fact of the matter is, though our actual results with IOMeter appear to be accurate, it is debatable whether or not certain access patterns, as they are presented to and measured on an SSD, actually provide a valid example of real world performance, at least for the average end user. That said, we do think Iometer is a solid gauge for relative available bandwidth with a given storage solution. Regardless, here's a sampling of our test runs with Iometer version 2006.07.27 with the OCZ Z-Drive and our complement of Intel's SSDs.
Here we dropped in a single Intel SSD as well, for a reference baseline metric. In our database or server access pattern, which is comprised of completely random access with 33% dedicated to write transactions, you can see the Intel X25-M RAID array scales dramatically as you add more drives to the equation and turn up the number of IO requests per target. Unfortunately this was not the case with the OCZ Z-Drive where the single card RAID solution topped out at roughly 11K IOPs and didn't scale beyond that as we increased IO queue depth.
In our Workstation access pattern, which consists of only 20% write operations and a bit more sequential access work, there are some rather interesting observations. Again, as you add drives to the Intel RAID 0 array, performance scales relatively well. In this test, the OCZ Z-Drive performed better as compared to its performance in the Database test but it still couldn't keep up with a single Intel 80GB gen 1 SSD.
Again, one thing to note is the transfer size of our standard Iometer tests. At small 8K transfer sizes, the Z-Drive takes a beating. In this next test, we'll simplify things a bit and show you how the Z-Drive fairs versus a single 160GB gen 2 Intel X25-M SSD but with larger file transfers
Here you're looking at an Iometer test run that is similar to our Workstation test pattern, except that we've taken the transfer request size up to 64K, which actually isn't all that large. Though overall IO throughput it lower since obviously it takes longer to transfer the larger file size, you can see the OCZ Z-Drive outperforms the Intel SSD by a large margin, on the order of about 40%.
So let's recap. The Z-Drive's strong suit is larger, sequential file transfers. Where it falls down is with respect to a heavy workload of small random read/write operations. We've observed this in a number of scenarios thus far in our testing. Let's look at a usage model that should play to the Z-Drive's strength, next.
Again, one thing to note is the transfer size of our standard Iometer tests. At small 8K transfer sizes, the Z-Drive takes a beating. In this next test, we'll simplify things a bit and show you how the Z-Drive fairs versus a single 160GB gen 2 Intel X25-M SSD but with larger file transfers
Here you're looking at an Iometer test run that is similar to our Workstation test pattern, except that we've taken the transfer request size up to 64K, which actually isn't all that large. Though overall IO throughput it lower since obviously it takes longer to transfer the larger file size, you can see the OCZ Z-Drive outperforms the Intel SSD by a large margin, on the order of about 40%.
So let's recap. The Z-Drive's strong suit is larger, sequential file transfers. Where it falls down is with respect to a heavy workload of small random read/write operations. We've observed this in a number of scenarios thus far in our testing. Let's look at a usage model that should play to the Z-Drive's strength, next.
