Adaptec 2074700-R - ICP Vortex GDT8514RZ RAID Controller, Руководство пользователя

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Software Installation and User’s Guide 19
Introduction
Figure 1-4. RAID 4 - Data Striping With a Dedicated Parity Drive
1.3.4 RAID 5 - Data Striping with Striped Parity
Unlike RAID 4, the parity data in a RAID 5 disk array are striped across all hard disks
(
Figure 1-5 ). The RAID 5 disk array delivers a balanced throughput. Even with small data
blocks, which are very likely in a multi-tasking and multi-user environment, the response
time is very good. RAID 5 offers the same level of security as RAID 4. When one hard
disk fails, all data is still fully available. Missing data is recalculated from the existing
data and parity information. RAID 4 and RAID 5 are particularly suitable for systems with
medium to large capacity requirements, due to their efficient ratio of installed and
available capacity.
Figure 1-5. RAID 5
-
Data Striping with Striped Parity
1.3.5 RAID 10 - Combination of RAID 1 and RAID 0
RAID 10 is a combination of RAID 0 (Performance) and RAID 1 (Data Security). See
Figure 1-6 . Unlike RAID 4 and RAID 5, there is no need to calculate parity information.
RAID 10 disk arrays offer good performance and data security. As in RAID 0, optimum
performance is achieved in highly sequential load situations. Identical to RAID 1, 50% of
the installed capacity is lost through redundancy.