1 - When a file is written in a vector mirrored disk drives, the controller sends both copies
File identical to each unit forming the assembly.
Mirroring can be done from two
disk drives.
2 - When a vector file mirrored disk is to be read, the controller simultaneously search
alternating clusters of this file in each of the units, putting them together (in ordered sequence) to be
sent to the PC.
This process makes reading faster, but the speed depends on the number of mirrored drives in the array.
If there are only two, the reading time is reduced by half, approximately, three mirrored drives, the time may
drop by about one third in relation to a unit.
3 - In case of a read error - caused by defect in the surface of one of the units or damage occurred in
one - the parent simply reads the version of the file intact on the drive that does not display any defects.
4 - If the read error is caused by a defect in the media, the controller automatically reads data from a copy of the
file on another drive, burning it to a new area and no defect in the unit in which the problem occurred.
Source: Evolution of Computers
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