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Intel IOMeter File Server and Web Server Patterns

Let’s start with the File Server pattern:

The next diagram shows the dependence of the array speed on the request queue depth:

The RAID0 arrays are excellently scalable in the number of drives per array, even at small queue depths. The RAID1 and the RAID10 are always considerably faster than the single drive and the two-disk RAID0, respectively. Since there are only 20 percent of write requests in the File Server pattern, the mirroring algorithms of the RAID1 and the RAID10 work well enough. By the way, this is the first test where the RAID1 is confidently faster than the single drive. To compare the performance of the arrays we calculate their performance ratings by averaging the controller’s speeds under all loads.

That’s just an ideal picture: the four-disk RAID0 takes the first position. The RAID10 and RAID1 are much faster than the two-disk RAID0 and the single drive, respectively. The drive with disabled TCQ has the worst performance here.

Next goes the Web Server pattern:

And the graphs:

Like in the File Server pattern, the RAID0 arrays boast an excellent scalability in the number of drives per array even at small request queue depths. The lack of write requests allows the mirroring RAID1 and RAID10 arrays to show their best. The speed of the RAID10 almost equals that of the four-disk RAID0, while the RAID1 is always faster than the two-disk RAID0 in every mode.

Like in the previous pattern, the sorting of requests adds considerably to the speed.

We calculate the performance rating here like we do in the File Server pattern:

The rankings are different here compared to the File Server pattern, but quite expectable. Since the Web Server pattern includes read requests only, the mirroring arrays have a certain advantage over the others. That’s why the four-disk RAID0 is just a tiny bit better than the RAID10. The RAID1 is ahead of the two-disk RAID0. The drive with disabled TCQ is the worst of all, like in the previous pattern.

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