Maximizing Drive Performance; Assigning Raid Levels; Table 7-9. Performance Characteristics For Each Raid Level; Table 7-10. Physical Drives Required For Each Raid Level - Dell PowerEdge Expandable RAID Controller 3 User Manual

Ta b l e 7 - 8 . Fa u l t To l e r a n c e Fe a t u r e s f o r R A I D L e v e l s 0 , 1
a n d 5 (continued)
RAID Fault Tolerance Protection
Level
5 100% protection through striping and parity. The data is striped and
parity data is written across a number of physical disk drives.

Maximizing Drive Performance

You can configure an array for optimal performance; however, optimal drive
configuration for one type of application will probably not be optimal for
any other application. A basic guideline of the performance characteristics
for RAID drive arrays at each RAID level is shown in Table 7-9.
Ta b l e 7 - 9 . P e r f o r m a n c e C h a r a c t e r i s t i c s f o r E a c h R A I D
L e v e l
RAID Performance Characteristics
Level
0 Excellent for all types of input/output (I/O) activity, but provides no
data security.
1 Provides data redundancy and good performance.
5 Provides data redundancy and good performance in most
environments.
10 Provides high data transfers and complete data redundancy.
50 Provides high data transfers and data redundancy.

Assigning RAID Levels

Only one RAID level can be assigned to each logical drive. The drives
required per RAID level shown in Table 7-10.
Ta b l e 7 - 1 0 . P h y s i c a l D r i v e s R e q u i r e d f o r E a c h R A I D L e v e l
RAID Minimum Number of
Level Physical Drives
0 1
1 2
Maximum Number of Physical
Drives
32
2
Configuring PERC 3
95