EVGA X299 FTW-K User Manual page 56

EVGA X299 FTW - K (142-SX-E297)
o Due to the capacity available on modern drive solutions, this issue may
not be as significant as it once was.
Write speed will be a bit lower than a single drive.
•
In the charts below, you can see the effect of fault tolerance when using a mirror array:
because all data has a direct 1-to-1 duplicate on the mirrored drive, you can suffer a
catastrophic failure of a drive and still retain your data.
For a RAID1 array to lose its data, both drives must fail.
RAID 1 (2 Drive)
P-DRIVE1 P-DRIVE2
DATA-A DATA-A
L-Drive = DATA-A
P-DRIVE1 P-DRIVE2
DATA-A DATA-A
L-Drive = DATA-A
RAID5
: RAID5 is a stripe with Fault Tolerance, which attempts to bridge the gap
between speed and redundancy. This level will always reserve a capacity equivalent to
one drive for fault tolerance, regardless of the overall capacity. This means that if you
use four 1TB drives to create your RAID5, you will only have the capacity of three 1TB
drives; likewise, if you use five 1TB drives to create your array, you will only have the
capacity of four 1TB drives. RAID5 requires a minimum of three drives, and the
maximum is set by the RAID controller; this level works well when using between four
to six drives, but sees diminishing returns beyond six.
Similar to RAID1, or any other current type of array with fault tolerance, a RAID5 array
is still usable even while it is experiencing a missing or failed drive resulting in the array
functioning in a degraded state. Performance will suffer in a degraded state until the
missing drive is replaced and the software rebuild process is completed. During the
rebuild process, performance will be severely degraded and can take several hours,
depending on the size of the array and percentage of capacity used.
L-DRIVE = ≃ 1TB
P-DRIVE1 P-DRIVE2
DATA-A DATA-A
L-Drive = DATA-A
P-DRIVE1 P-DRIVE2
DATA-A DATA-A
L-Drive = DATA-A
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