The Performance Advantage of
More Drives
MFT performance is a function of the performance of an individual drive times the number of data drives used.
On the read side, the maximum random read performance of a single process in a system will always be the random read speed of an individual drive. However, when there are multiple operations, as long as these operations exceed the number of drives, total random reads will expand to the multiple: drive-performance times the number of drives.
On the random write side, the addition of another drive in a RAID-0 or RAID-5 stripe will increase the total write thruput of the system by the linear write megabytes made available by that drive. This is true whether the computer is operating single-threaded or multi-threaded.
In this respect, MFT RAID performance is very different than hard drives. In hard drives, there is little efficiency gain for broader arrays. Instead, more arrays make more sense. In MFT, a 15 drive single array is more effective than a 14 drive array, and one 14 drive array will always perform significantly better than two 7 drive arrays.
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