D-Link DSN-626 User Manual - Page 98

Features Highlight, Write on demand or allocate on demand.

Get D-Link DSN-626 PDF manuals and user guides View all D-Link DSN-626 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 98 highlights

D-Link Document - User Manual level of services with less hard drives purchased upfront, which can significantly reduce your total cost of ownership.  Scalability: storage pool can grow on demand. When the storage pool (RAID group) has reached the threshold you set before. Up to 32 RAID sets can be added to the RAID group to increase the capacity on demand without interrupting I/O. Each RAID set can have up to 64 physical disks.  Automatic space reclamation mechanism to recycle unused blocks. The technology used here is called zero reclamation. When a thin RG is created, the initialization process will try to fill out all the storage pool space with zero. This process will run in background with low priority in order not to impact the I/O performance. This is the reason why when there is no I/O traffic from the hosts, the hard drive LED will keep blinking as if there are I/O activities. The purpose of zero reclamation is that when the actual user data happens to have all zero in a basic allocation unit (granularity), the storage system will treat it as free space and recycle it. Until the next time there is data update to this reclaimed all zero basic unit, the storage system can swiftly return a basic unit from the free storage pool because it's already filled with zero.  An eco-friendly green feature that helps to reduce energy consumption. Hard drive is the top power consumer in a storage system. Because you can use less hard drives to achieve the same amount of work, this translates directly to a huge reduction of power consumption. Features Highlight The following describes the comparison between Fat and Thin provisioning.  Write on demand or allocate on demand. This is the most distinctive function in thin provisioning. You can see from the screenshots below. Figure 1 shows there are two RAID groups created. "Fat-RG" is using traditional provisioning without Thin provisioning enabled and its size is 1862GB. "Thin-RG" is Thin provisioning enabled and it's size is the same. Figure 1: No virtual disk is created Let's create a Virtual Disk on each RAID group with the same size of 1000GB respectively in Figure 2 and see what happens. Copyright@2014 D-Link System, Inc. All Rights Reserved. 98

  • 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
D-Link Document – User Manual
level of services with less hard drives purchased upfront, which can significantly reduce your total
cost of ownership.
Scalability: storage pool can grow on demand.
When the storage pool (RAID group) has reached the threshold you set before. Up to 32 RAID sets
can be added to the RAID group to increase the capacity on demand without interrupting I/O. Each
RAID set can have up to 64 physical disks.
Automatic space reclamation mechanism to recycle unused blocks.
The technology used here is called zero reclamation. When a thin RG is created, the initialization
process will try to fill out all the storage pool space with zero. This process will run in background
with low priority in order not to impact the I/O performance. This is the reason why when there is
no I/O traffic from the hosts, the hard drive LED will keep blinking as if there are I/O activities. The
purpose of zero reclamation is that when the actual user data happens to have all zero in a basic
allocation unit (granularity), the storage system will treat it as free space and recycle it. Until the
next time there is data update to this reclaimed all zero basic unit, the storage system can swiftly
return a basic unit from the free storage pool because it’s already filled with zero.
An eco-friendly green feature that helps to reduce energy consumption.
Hard drive is the top power consumer in a storage system. Because you can use less hard drives to
achieve the same amount of work, this translates directly to a huge reduction of power
consumption.
Features Highlight
The following describes the comparison between Fat and Thin provisioning.
Write on demand or allocate on demand.
This is the most distinctive function in thin provisioning. You can see from the screenshots below.
Figure 1 shows there are two RAID groups created. "Fat-RG" is using traditional provisioning
without Thin provisioning enabled and its size is 1862GB. "Thin-RG" is Thin provisioning enabled
and it's size is the same.
Figure 1: No virtual disk is created
Let's create a Virtual Disk on each RAID group with the same size of 1000GB respectively in Figure
2 and see what happens.
98
Copyright@2014 D-Link System, Inc. All Rights Reserved.