OCZ IBIS HSDL Solid State Drive Preview

Our Test Methodologies:  Under each test condition, the Solid State Drives tested here were installed as secondary volumes in our testbed, with a standard spinning hard disk for the OS and benchmark installations.  A low-level format was performed on all SSDs prior to testing.  The SSDs were left blank without partitions wherever possible, unless a test required them to be partitioned and formatted, as was the case with our Vantage benchmark tests. AHCI was enabled in the system BIOS before installation of Windows 7 Ultimate x64.  Windows firewall, automatic updates and screen savers were all disabled before testing. In all test runs, we rebooted the system and waited several minutes for drive activity to settle before invoking a test.

HotHardware Test System Intel Core i7 Powered

IOMeter  I/O Subsystem Measurement Tool

The IOMeter Question:
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.  The fact of the matter is, though our actual results with IOMeter appear to scale properly, 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 for the average end user.  That said, we do think IOMeter is a gauge for relative available bandwidth with a given storage solution.

In the following tables, we're showing two sets of access patterns; our Workstation pattern with an 8K transfer size, 80% reads (20% writes) and 80% random (20% sequential) access and our Database access pattern of 4K transfers, 67% reads (34% writes) and 100% random access.

The first thing you'll note here is how flat the standard SATA SSD's performance was across test patterns and IO queue depth.  Our IO queue depth was set in IOMeter and essentially it represents higher levels of workload requests of the same access patterns simultaneously.  The Vertex LE SSD was saturated here as we turned up queue depth, however, the Fusion--io ioXtreme and OCZ IBIS drives scaled up significantly at higher request levels.  The IBIS drive actually started to level off above a queue depth of 144 in the database test but scaled slightly higher still in the workstation test.  The ioXtreme SSD topped out at nearly 84000 IOPS in the database test, while the IBIS drive peaked at nearly 50,000 IOPS.  In the workstation test the field was grouped tighter with the ioXtreme hitting a wall at 65K or so, while the IBIS drive cleared 44K IOPS. 

We would offer that the 12 - 144 queue depth ranges are probably more indicative of standard desktop and workstation performance.  Also, note that the Fusion-io ioXtreme's cost per GB ratio is about $10 or so, while the IBIS drive drops in at a little over $3/GB or $3.08 to be exact.