Intel AFCSASRISER User Guide - Page 29

Table 8. RAID 60 Overview

Get Intel AFCSASRISER PDF manuals and user guides View all Intel AFCSASRISER manuals
Add to My Manuals
Save this manual to your list of manuals

Page 29 highlights

Table 8. RAID 60 Overview Uses Strong Points Weak Points Drives Provides a high level of data protection through the use of a second parity block in each stripe. Use RAID 60 for data that requires a very high level of protection from loss. In the case of a failure of one drive or two drives in a RAID set in a virtual disk, the RAID controller uses the parity blocks to recreate all the missing information. If two drives in a RAID 6 set in a RAID 60 virtual disk fail, two drive rebuilds are required, one for each drive. These rebuilds do not occur at the same time. The controller rebuilds one failed drive, and then the other failed drive. Use for office automation, online customer service that requires fault tolerance or for any application that has high read request rates but low write request rates. Provides data redundancy, high read rates, and good performance in most environments. Each RAID 6 set can survive the loss of two drives or the loss of a drive while another drive is being rebuilt. Provides the highest level of protection against drive failures of all of the RAID levels. Read performance is similar to that of RAID 50, though random reads in RAID 60 might be slightly faster because data is spread across at least one more disk in each RAID 6 set. Not well suited to tasks requiring a lot of writes. A RAID 60 virtual disk has to generate two sets of parity data for each write operation, which results in a significant decrease in performance during writes. Disk drive performance is reduced during a drive rebuild. Environments with few processes do not perform as well because the RAID overhead is not offset by the performance gains in handling simultaneous processes. RAID 6 costs more because of the extra capacity required by using two parity blocks per stripe. A minimum of 6. The following figure shows a RAID 6 data layout. The second set of parity drives are denoted by Q. The P drives follow the RAID 5 parity scheme. Note: When only three hard drives are available for RAID 6, the situation has to be that P equals Q equals original data, which means that the three hard drives have the same original data, which can afford two disk failures. Intel® RAID Software User's Guide 17

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
Intel
®
RAID Software User’s Guide
17
Table 8. RAID 60 Overview
The following figure shows a RAID 6 data layout. The second set of parity drives are denoted
by
Q
. The
P
drives follow the RAID 5 parity scheme.
Note:
When only three hard drives are available for RAID 6, the situation has to be that P equals Q equals
original data, which means that the three hard drives have the same original data, which can afford
two disk failures.
Uses
Provides a high level of data protection through the use of a second parity block in
each stripe. Use RAID 60 for data that requires a very high level of protection from
loss.
In the case of a failure of one drive or two drives in a RAID set in a virtual disk, the
RAID controller uses the parity blocks to recreate all the missing information. If
two drives in a RAID 6 set in a RAID 60 virtual disk fail, two drive rebuilds are
required, one for each drive. These rebuilds do not occur at the same time. The
controller rebuilds one failed drive, and then the other failed drive.
Use for office automation, online customer service that requires fault tolerance or
for any application that has high read request rates but low write request rates.
Strong Points
Provides data redundancy, high read rates, and good performance in most
environments. Each RAID 6 set can survive the loss of two drives or the loss of a
drive while another drive is being rebuilt. Provides the highest level of protection
against drive failures of all of the RAID levels. Read performance is similar to that
of RAID 50, though random reads in RAID 60 might be slightly faster because
data is spread across at least one more disk in each RAID 6 set.
Weak Points
Not well suited to tasks requiring a lot of writes. A RAID 60 virtual disk has to
generate two sets of parity data for each write operation, which results in a
significant decrease in performance during writes. Disk drive performance is
reduced during a drive rebuild. Environments with few processes do not perform
as well because the RAID overhead is not offset by the performance gains in
handling simultaneous processes. RAID 6 costs more because of the extra
capacity required by using two parity blocks per stripe.
Drives
A minimum of 6.