Adaptec 5405 User Guide - Page 154

Non-redundant Logical Drives (RAID 0)

Page 154 highlights

Appendix B: Selecting the Best RAID Level ● 154 Non-redundant Logical Drives (RAID 0) A logical drive with RAID 0 includes two or more disk drives and provides data striping, where data is distributed evenly across the disk drives in equal-sized sections. However, RAID 0 arrays do not maintain redundant data, so they offer no data protection. Compared to an equal-sized group of independent disks, a RAID 0 array provides improved I/O performance. Drive segment size is limited to the size of the smallest disk drive in the logical drive. For instance, a logical drive with two 250 GB disk drives and two 400 GB disk drives can create a RAID 0 drive segment of 250 GB, for a total of 1000 GB for the volume, as shown in this figure. Disk Drive 1 250 GB Drive Segment Size (Smallest Disk Drive) Disk Drive 2 250 GB Disk Drive 3 400 GB Disk Drive 4 400 GB Disk Drives in Logical Drive Disk Drive 1 1 5 ... 997 Disk Drive 2 2 6 ... 998 Disk Drive 3 3 7 ... 999 Disk Drive 4 4 8 ... 1000 Unused Space = 150 GB Unused Space = 150 GB RAID 0 Logical Drive = 1000 GB

  • 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

Appendix B: Selecting the Best RAID Level
154
Non-redundant Logical Drives (RAID 0)
A logical drive with RAID 0 includes two or more disk drives and provides data
striping
, where
data is distributed evenly across the disk drives in equal-sized sections. However, RAID 0
arrays do not maintain redundant data, so they offer
no data protection
.
Compared to an equal-sized group of independent disks, a RAID 0 array provides improved I/O
perfor
mance.
Drive segment size is limited to the size of the smallest disk drive in the logical drive. For
instance, a logical drive with two 250 GB disk drives and two 400 GB disk drives can create a
RAID 0 drive segment of 250 GB, for a total of 1000 GB for the volume, as shown in this figure.
Disk Drive 1
Disk Drive 2
Disk Drive 3
Disk Drive 4
250 GB
250 GB
400 GB
400 GB
Drive Segment Size (Smallest Disk Drive)
Disk Drive 2
Disk Drive 3
Disk Drive 4
Disk Drive 1
1
5
...
997
2
6
...
998
3
7 ...
999
4
8
... 1000
Unused Space = 150 GB
Disk Drives in Logical Drive
RAID 0 Logical Drive = 1000 GB
Unused Space = 150 GB