Operating system and file system capacity
When initializing a DP-VOL operating systems and file systems will consume some Dynamic Provisioning pool space. Some combinations initially take up little pool space, while other combinations take as much pool space as the virtual capacity of the DP-VOL.
The following table shows the effects of some combinations of operating system and file system capacity. For more information, contact your service representative.
|
OS |
File System |
Metadata Writing |
Pool Capacity Consumed |
|
Windows Server 2003, Windows Server 2008* |
NTFS |
Writes metadata to first block. |
Effective reduction of pool capacity: Small (one page) If file update is repeated, allocated capacity increases when files are updated (overwritten). Therefore, the effectiveness of reducing the pool capacity consumption decreases. |
|
Linux |
XFS |
Writes metadata in Allocation Group Size intervals. |
Effective reduction of pool capacity: Depends upon allocation group size. The amount of pool space consumed will be approximately [DP-VOL Size] × [42 MB/Allocation Group Size] |
|
Ext2 Ext3 |
Writes metadata in 128-MB increments. |
Effective reduction of pool capacity: About 33% of the size of the DP-VOL. The default block size for these file systems is 4 KB. This results in 33% of the DP-VOL acquiring DP pool pages. If the file system block size is changed to 2 KB or less then the DP-VOL Page consumption becomes 100%. | |
|
Solaris |
UFS |
Writes metadata in 52-MB increments. |
No effective reduction of pool capacity. Size of DP-VOL. |
|
VxFS |
Writes metadata to the first block. |
Effective reduction of pool capacity: Small (one page). | |
|
AIX |
JFS |
Writes metadata in 8-MB increments. |
No effective reduction of pool capacity. Size of DP-VOL. If you change the Allocation Group Size settings when you create the file system, the metadata can be written to a maximum interval of 64 MB. Approximately 65% of the pool is used at the higher group size setting. |
|
JFS2 |
Writes metadata to the first block. |
Effective reduction of pool capacity: Small (one page). | |
|
VxFS |
Writes metadata to the first block. |
Effective reduction of pool capacity: Small (one page). | |
|
HP-UX |
JFS (VxFs) |
Writes metadata to the first block. |
Effective reduction of pool capacity: Small (one page). |
|
HFS |
Writes metadata in 10-MB increments. |
No effective reduction of pool capacity. Size of DP-VOL. | |
|
* In a Windows environment, both Normal Format and Quick Format are commonly used. In this environment, Quick Format consumes less thin provisioning pool capacities than Normal Format:
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