The linear read speeds are the same for NTFS and FAT32, so we will show you just two diagrams for the both file systems:

The linear read speed is supposed not to depend on the status of lazy writing, as there are no write requests here. However, the RAID5 does show its dependence on the WB caching. The speed grows in the beginning of the array and drops down in the end. That’s a curious array!

The graphs of linear reading are given by the following links:

• Linear read graph for JBOD (1 HDD);
• Linear read graph for RAID1 (2 HDDs);
• Linear read graph for RAID0 (2 HDDs);
• Linear read graph for RAID0 (3 HDDs);
• Linear read graph for RAID5 (3 HDDs);
• Linear read graph for RAID0 (4 HDDs);
• Linear read graph for RAID5 (4 HDDs);
• Linear read graph for RAID10 (4 HDDs).

Conclusion

Promise FastTRAK S150 SX4 controller we have reviewed today is a good piece of hardware. It is especially good in tests that simulate real-life applications. Our only question regarding it concerns the results of the three-disk RAID5: its performance was higher than expected with WT caching (or maybe we tested a three-disk RAID5 once again instead of a four-disk configuration?).

The low performance with sequential requests and the negligible influence of a large cache (256MB) are topics that only specialists take interest in. We prepare an independent article to cover these issues where we will examine the speed of the Promise FastTRAK S150 SX4 with 64, 128 and 256MB modules for the cache memory.

Currently, the manufacturer’s website offers to download drivers for Windows 2003/XP/2000, SuSE Linux, Red Hat 8x and 9x Linux. The Russian-language site site (www.promise.ru) claims there is a driver for FreeBSD 4.8 Beta, but www.promise.com only says “FreeBSD 4.7 coming soon”.