Accusys ExaRAID GUI - Manual (Page 220)

Advanced Functions
5-47
• Disk group expansion to create a free chunk
If the disk group has no free chunks in the end space before expansion, a
new free chunk will be created.
• Disk group expansion to consolidate free chunks
When disk group expansion is executed in a disk group where free chunks
between logical disks exist, the free chunks are consolidated and placed
in the end space of the disk group after expansion.
Note
It is suggested that defragmentation should be performed during
disk group expansion. In the cases shown in Figures 5-24, 5-25, and
5-26, defragmentation forms an organized collocation for all logical
disks and free chunks after expansion.
Figure 5-24 Disk group expansion by adding new
member disks and enlarging the last free
Disk group (before) Disk group (after)
MD 0 MD 1 MD 2
LD 0
LD 1
LD 2
Free
chunk
MD 0 MD 1 MD 2 MD 3 MD 4
LD 0
LD 1
LD 2
Free
chunk
Disk group (before) Disk group (after)
LD 0
LD 1
LD 2
LD 3
Free
chunk
LD 0
LD 1
LD 2
LD 3
MD 0 MD 1 MD 2 MD 3 MD 4 MD 0 MD 1 MD 2
Figure 5-25 Disk group expansion by adding new
member disks and creating a new free chunk
LD 1
LD 1
Free
chunk
LD 3
LD 3
Disk group (before) Disk group (after)
MD 0 MD 1 MD 2 MD 3 MD 4 MD 0 MD 1 MD 2
Free
chunk
Free
chunk
Figure 5-26 Disk group expansion to consolidate free