Memory for disk arrays
For example, if five disks to the size 10 GB, the actual array size is 40
gigabytes, as well as 10 GB is a checklist for information. RAID 5, as well as
RAID 4, the architecture is independent of access, that is, unlike RAID 3 is a
large amount of logical blocks to store information. Therefore, as with RAID 4,
the main such gains at the same time provides an array processing Pack several
queries. The main difference between a RAID 5 and RAID 4 is a way to control the
amounts. The existence of a separate disk (physical), holds a controlling
information about the amounts here, as in the previous three levels, has
resulted in the operation of reading, not requiring treatment on the drive,
executed with great speed. However, with each transaction record changing
information on Controller drive, so the scheme RAID 2, RAID 3 and RAID 4 does
not allow for parallel operation. RAID 5 deprived of this shortcoming, as
checksums recorded on the disks arrays, which provide the ability to run
multiple operations simultaneously Read, and Write. Advantages: -- High-speed
data recording; -- sufficiently high speed reading data; -- high productivity
with high-intensity queries read / write data; -- small overhead for the
implementation of redundancy.
Next part
|
O
wlCom Software
