Asus DS300j G2 Series User Manual page 192

• Imaging applications
• Database servers
• General fileserver
rAid 3 - b s d P
lock triPe And edicAted Arity
RAID 3 organizes block data across multiple physical drives and parity data on a dedicated drive. Generally, RAID
Level 3 tends to exhibit lower random write performance due to the heavy workload of parity recalculation for each
I/O. Heavy I/O loads with a large number of writes tends to work the parity drive harder in proportion to the other
drives in the logical drive. ASUS Storage implements RAID 3 with block-level striping, rather than byte-level striping.
Advantages
• Good for large files with high transfer
rates where fault tolerance is also
required
Recommended Applications for RAID 3:
• Video editing
• Multimedia production
• File and application server
rAid 5 – b P s
lock And Arity triPe
RAID 5 organizes block data and parity data across the physical drives. Generally, RAID Level 5 tends to
exhibit lower random write performance due to the heavy workload of parity recalculation for each I/O. RAID 5
is generally considered to be the most versatile RAID level. It works well for file, database, application and web
servers.
The capacity of a RAID 5 logical drive equals the smallest physical drive times the number of physical drives,
minus one. Hence, a RAID 5 logical drive with four 100 GB physical drives has a capacity of 300 GB. A RAID 5
logical drive with two 120 GB physical drives and one 100 GB physical drive has a capacity of 200 GB.
RAID 5 is generally considered to be the most versatile RAID level.
A RAID 5 on ASUS DS300f G2 consists of 3 to 32 physical drives.
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Disadvantages
• Random write performance only fair.
Disk failure has a medium impact on
throughput
Advantages
• High Read data transaction rate
• Medium Write data transaction rate
• Good aggregate transfer rate
• Most versatile RAID level
Recommended Applications for RAID 5:
• File and Application servers
• WWW, E-mail, and News servers
• Intranet servers
rAid 6 – b d P s
lock And ouble Arity triPe
RAID level 6 stores dual parity data is rotated across the physical drives along with the block data. A RAID 6
logical drive can continue to accept I/O requests when any two physical drives fail.
Hence, a RAID 6 logical drive with (7) 100 GB physical drives has a capacity of 500 GB. A RAID 6 logical drive
with (4) 100 GB physical drives has a capacity of 200 GB.
RAID 6 becomes more capacity efficient in terms of physical drives as the number of physical drives increases.
RAID 6 provides double fault tolerance. Your logical drive remains available when up to two physical drives fail.
RAID 6 is generally considered to be the safest RAID level.
A RAID 6 on ASUS DS300f G2 consists of 4 to 32 physical drives.
Advantages
• High Read data transaction rate
• Medium Write data transaction rate
• Good aggregate transfer rate
• Safest RAID level, except for RAID 60
Recommended Applications for RAID 6:
• Accounting and Financial
• Database servers
• Any application requiring very high availability
rAid 10 – M + s
irror triPe
DS300f G2 Series User Manual
Disadvantages
• Disk failure has a medium impact on
throughput
Disadvantages
• High disk overhead – equivalent of two drives used
for parity
• Slightly lower performance than RAID 5