The SuperTrak's RAID 3 Performance...
The SuperTrak's performance thus far likely disappoints lots of folks. Unlike the Escalade, however, the Promise controller supports RAID 3-4. Let's see how the SuperTrak fares.
Note: Although none of Promise's documents mention RAID 4 support for the SuperTrak, it does indeed support this RAID level. The only difference between RAID 3 and RAID 4 is stripe size: RAID 3 uses very small stripe sizes such as 512 bytes or 1K, while the term RAID 4 generally implies a stripe size of over 1K. Since the SuperTrak allows stripe sizes up to 1MB, one can configure a "RAID 3" array on the SuperTrak with a stripe size over 1K. This, in effect,, is a RAID 4 array.
In the results below, RAID 3 arrays used a stripe size of 1K, while RAID 4 arrays utilize a 64K stripe.
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Ziff Davis WinBench 99 under Windows 2000 Professional using NTFS - RAID 3
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| Benchmark |
SuperTrack-100 w/ 3 Drives |
SuperTrack-100 w/ 4 Drives |
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| Business Disk WinMark 99 (KB/sec) |
3952 |
3870 |
| High-End Disk WinMark 99 (KB/sec) |
6118 |
6116 |
| AVS/Express 3.4 (KB/sec) |
11020 |
11500 |
| FrontPage 98 (KB/sec) |
51660 |
52200 |
| MicroStation SE (KB/sec) |
15080 |
15720 |
| Photoshop 4.0 (KB/sec) |
2462 |
2480 |
| Premiere 4.2 (KB/sec) |
3806 |
3850 |
| Sound Forge 4.0 (KB/sec) |
6122 |
6172 |
| Visual C++ (KB/sec) |
7394 |
7494 |
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| Disk/Read Transfer Rate | StorageReview.com |
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| Beginning (KB/sec) |
16333 |
16300 |
| End (KB/sec) |
16367 |
16300 |
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| Disk Access Time (ms) |
16.12 |
16.12 |
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| Disk CPU Utilization (%) |
2.88 |
2.85 |
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While the Business Disk Winmark scores shown above may indeed represent the SuperTrak's RAID 3 performance, it's very difficult to believe that the High-End Winmark scores are accurate.
As we'll see, a contrast against base, single-drive scores reveals RAID 3 Business Winmark scores trailing by about 20%. IOMeter backs these scores up.
The High-End Winmark scores, however, weigh in at less than half that of base. This again throws up a red flag, and further investigation reveals that the array's drive activity simply stops at various points during the HE test for a minute or more. This activity, while not as severe as it was with RAID 5, still invalidates the results.
Also disappointing is the SuperTrak's apparent sustained transfer rate of 16 MB/sec in RAID 3. The previous 20 MB/sec limit in RAID 0/1/01 was bad enough. One uses RAID 3, after all, when sustained transfer rates are more important. We have a hard time imagining any other situations where RAID 3 would be desirable - it's small stripe size results in poor random I/O performance since the vast majority of I/O requests must be serviced by multiple drives. (For a more detailed explanation of various RAID levels and their respective performance, please see our RAID guide.)
The SuperTrak's RAID 4 WinBench 99 Performance...
