Articles: Storage

Bookmark and Share

Pages: [ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 ]

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:

Everything is normal in the Create test except that the degraded RAID10 is too different from the healthy array without a cause. Perhaps it was trying to write to the failed disk and was waiting for the latter to respond. The arrays are generally as fast as on competitor controllers, but we might wish them to perform better after the results of the sequential writing test.

Interestingly, the RAID5 and RAID6 arrays are faster than the RAID0 and RAID10 on large files and comparable to them on other file-sets. The degraded arrays are surprisingly good. They are generally as fast as the healthy arrays (excepting the RAID5 with one failed disk in the ISO pattern).

The speeds are considerably higher at reading! Of course, they are not as high as in the sequential reading test, yet the RAID0’s 585MBps with large files is a very good speed (it will take only 8 seconds to read a DVD image, for example). Surprisingly, the degraded RAID10 suffers almost no performance hit.

We have high speeds when reading large files from the healthy RAID5 and RAID6. The degraded arrays are much slower.

There is something odd with small files: the degraded arrays gain the lead and we can’t explain this.

Copying within the same partition or between two partitions is almost the same here: the larger the files, the better the RAID0 are than the RAID10. The degraded RAID10 is not fast. It must be limited by its poor write speed.

The second group of arrays does not show anything exceptional at copying, either. The 8-disk arrays are faster than the 4-disk ones on large files. The RAID5 are ahead of the RAID6 just as expected.

Pages: [ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 ]


Comments currently: 7
Discussion started: 06/26/09 02:27:26 AM
Latest comment: 12/09/16 10:27:31 AM

View comments

Add your Comment