2. Performance Tests
We test the performance of the OCZ Rally 1GB USB 2.0 memory stick and compare it to the Memorex TD (TravelDrive) 1GB USB 2.0, using two well known benchmarking utilities, HD Tach and Sisoft Sandra 2005. All tests were made under WinXP with a USB 2.0 compatible motherboard (Abit A8N Fatal1ty series).
HD Tach Results
In the reading tests, the OCZ Rally reported 14.5MB/s and the Memorex TravelDrive 17.4MB/s, whilst in writing, the OCZ Rally reported 24.7MB/s and the Memorex TravelDrive 10.5MB/s. The difference between the two isn't that great in reading, but in writing the OCZ memory offers more than double the throughput of the Memorex.
Sisoft Sandra 2005 SR1 Results
Sisoft Sandra has two sets of tests.
The "File system" which tests how your drive(s) and controller(s) compare to other devices in a typical system:
· Read Test: Buffered, Random, Sequential
· Write Test: Buffered, Random, Sequential
· Seek Test
The "Drive Index" mark is a composite figure representing an overall performance rating based on the average of the read, write, and seek tests, and file and cache size. The Drive Index is intended to represent drive performance under typical use in a PC. A larger number means better performance. The weighting of the results is not equal and represents the distribution of different files sizes as used on these devices (obtained through field research).
The Drive Index achieved by the OCZ Rally is 18MB/s, 3MB/s better than the Memorex TravelDrive at 15MB/s.
The "Compact Flash" typical usage model for these devices is File operations, such as Writing a file to the device, reading a file from it, and deleting a file. This benchmark exercises the devices in terms of these operations (to measure the “raw” cluster level performance of the device, it is recommended to also test it by means of the File System Benchmark module). The following characteristics are measured for each of the four representative file sizes of 512 Bytes (representing a minimal single data cluster file), 32kB, 256kB and 2MB. The weighting of the results is not equal and it represents the distribution of different files sizes as used on these devices (obtained through field research). For each of the four file sizes, a Combined Index is then calculated, stating the combined performance in terms of Combined Operations Per Second, with respect to a mix of write, read and delete operations.
Combined Device Index: is a composite figure representing an overall performance rating based on the average of the Combined Index figures over the four file sizes. (Higher is better, i.e. better performance).
Endurance Factor: is a figure representing the Wear and Life Expectancy of flash devices; this is obtained by dividing the average performance (normal condition, i.e. sequential write) to the lowest performance (high-stress condition, i.e. same block re-write). It measures the relative improvement of endurance caused by the wear leveling or flash management algorithm; the absolute endurance of a device (i.e. its expected life-time) is directly dependent, in addition to this Endurance Factor, on the nominal manufacturer rating of maximum erase/reprogram cycles, which is typically 100,000+ for SLC and 10,000+ for MLC devices. (Higher is better, i.e. longer life-time for the device)
The OCZ Rally achieved a higher combined operations index as we would expect, due to it's higher performance rating seen in the previous tests. The higher Endurance Factor though was clocked in by the Memorex TravelDrive USB stick, which if these figures are accurate, indicates that the Memorex TravelMate has a life time expectancy 4 times greater than that of the OCZ USB stick.