Performance in FC-Test

For this test two 32GB partitions are created on the virtual disk of the RAID array and formatted in NTFS and then in FAT32. Then, a file-set is created on it. The file-set is then read from the array, copied within the same partition and then copied into another partition. The time taken to perform these operations is measured and the speed of the array is calculated. The Windows and Programs file-sets consist of a large number of small files whereas the other three patterns (ISO, MP3, and Install) include a few large files each.

We’d like to note that the copying test is indicative of the array’s behavior under complex load. In fact, the array is working with two threads (one for reading and one for writing) when copying files.

This test produces too much data, so we will only discuss the results of the Install, ISO and Programs patterns in NTFS which illustrate the most characteristic use of the arrays. You can use the links below to view the other results:

• FC-Test: NTFS
• FC-Test: FAT32

Well, the RAID0 arrays are not as bad after all as we might expect after the sequential writing test. They do not deliver the speed we want, though. The speed of writing files is about 2.5 times lower than necessary. It is odd that the arrays reach their top speeds in the Install pattern rather than with the large files of the ISO file-set. The ISO results are really strange besides the generally low speeds. For example, the 4-disk RAID0 is twice as fast as the 8-disk RAID10 although they should be equals. The degraded RAID10 is somehow faster than the healthy one. So, the controller does have problems with writing.

The RAID5 and RAID6 arrays have problems, too. Like in the sequential writing test first places go to the degraded arrays, which is nonsense. Moreover, the 8-disk arrays are very slow with the large files of the ISO pattern: funnily, the 4-disk RAID5 is 50% faster than the 8-disk one. It is only with the small files of the Programs pattern that the standings are more or less all right but the speeds are no good there, either.

The controller seems to hit some speed limitation at reading: the RAID0 and RAID10 arrays all have about the same speeds. It is funny with the Install pattern: the arrays’ read speed is lower than their write speed. The speed of reading large files is good, though. This controller’s read speed ceiling is much higher than that of any other controller we have tested before. The 3ware 9690SA could not yield over 160MBps while the Adaptec easily delivers 400MBps.

By the way, judging by the speed of the 4-disk RAID10 the controller reads from both disks of the mirrors. Otherwise, we would not have a read speed higher than 250MBps.

And once again we see the 8-disk arrays hit the speed limitation when processing large files. The standings are overall what they should be, though. The degraded arrays slow down proportionally to the reduction of the number of disks in them.

The Copy Near test is reminiscent of the oddities we have seen at writing: all the arrays are faster with the Install rather than ISO files. The 8-disk RAID0 arrays are very slow while the 8-disk RAID10 is similar to the 4-disk RAID0, just as in theory. The degraded RAID10 performs well, being almost as fast as the healthy array.

We see the checksum-based arrays have the same problems with the large ISO files, but the problems are not so big now. The degraded arrays are not in the lead anymore. The standings are overall logical.

Copying from one partition to another produces roughly the same results as the Copy Near test. The only significant difference is that the 4-disk RAID5 and RAID6 have too low performance with the ISO files. The controller shows a strange dislike of large files. Its firmware calls for improvement.