What a difference Over Provisioning makes

Testing Approach


Testing was performed by three members of the Myce team (due
to the multiple locations of the SSDs tested).

As you will see in due course, it is really the shape and
pattern of the scores recorded for the SSD’s tested that matters and not the
absolute scores, so minor variances in test platforms and configuration are not
important to the conclusions drawn by this article.


A Secure Erase was performed at the start of every test

Each drive was tested with and without an additional OP.
When an additional OP was added the total space set aside (i.e. the normal OP
dedicated to the controller plus an additional OP) was 96GB.


IOmeter was used to
generate the test data and IO traffic.

The test run was configured in IOmeter, as follows:


Access Specification: Block Size – 4KB, 100% Write, 100% Random
IO, aligned to 4K boundaries

Disk Targets: Max Disk Size – 0 (so the test file covers the
full range of blocks available), number of Outstanding I/Os (Queue Depth) – 32,
Write IO Data Pattern – Full Random

Test Setup: Run Time was 2 hours

A User Defined Windows Performance Data Collector Set
(performance log) was used to record the ‘Disk Transfers/sec’ for the Logical
Drive being tested, at a sample interval of 1 second. The log file format
property was changed to ‘comma delimited’, so the results can easily be loaded
into MS Excel to produce a scatter chart of the results.

The log file was started just as IOmeter finishes creating
its test file and then stopped after the IOmeter run completes.


Let’s move to the next page to look at the results for an
Intel 520 256GB..