Memory for disk arrays
Type 2 (levels) RAID arrays In accordance with the different types of access,
building architecture and the distribution of memory, there are different types
of RAID-arrays, which are taken to characterize levels of RAID. Currently, there
are several standardized-RAID levels, which vary in speed, reliability and cost
of manufacturing: from RAID 0 to RAID 5. Besides being used combinations of
these levels, as well as corporate levels (such as RAID 6, RAID 7). The most
common are the levels of 0,1,3, and 5. In each of the levels of RAID solve the
problem of optimization of any of the parameters (or combination): reliability;
speed; capacity; value of the data storage units. The reliability of the entire
body decreases with an increase in the number of disks in the array. With the
refusal of independent law and exponential distribution developments in the
waiver, the entire body of MTTF (mean time to failure - the average time trouble)
is calculated by the formula: MTTFarray = MMTFhdd / Nhdd MMTFhdd - the average
time trouble one disk Nhdd - the number of disks Thus, there is a need to
increase reliability of disk arrays those involved. To increase reliability
arrays using excess coding. Creature-tions are two main types of encryption,
which are used in excess disk arrays - is duplication and parity.
Next part
|
O
wlCom Software
