Apple Xsan 2 (Third Edition) - Manual (Page 60)

For most volumes, the preset block allocation size and storage pool stripe breadth
result in good performance. However, in some cases you might be able to improve
read or write performance by adjusting these settings to suit a specific application.
For example, if your application reads and writes small blocks of data, you might
improve performance by choosing a correspondingly small block allocation size.
To set a volume’s block allocation size:
The block allocation size must be set when the volume is created and can’t be
m
changed for an existing volume. To set the block allocation size, click the Advanced
Settings button on the Volume Name and Type pane when you first add the volume.
Changing the Volume Allocation Strategy
You can change the allocation strategy for a volume to choose how storage for new
files or additional storage for existing files is allocated on the storage pools that
belong to the volume.
To change the allocation strategy:
1 In Xsan Admin, select Volumes in the SAN Assets list.
2 Select the volume in the list and choose Edit Volume Settings from the Action (gear)
pop-up menu.
3 Choose an allocation strategy from the pop-up menu:
Round Robin: Each request for space is assigned to the next available storage pool in
the volume.
Fill: All data is stored on the first storage pool until it’s full, then on the next storage
pool, and so on.
Balance: New data is written to the storage pool that has the most free space.
4 Click OK.
Enabling or Disabling Spotlight on a Volume
You can use Xsan Admin to control whether a volume is indexed and searchable using
Spotlight.
To enable or disable Spotlight on a volume:
1 In Xsan Admin, select Volumes in the SAN Assets list.
2 Select the volume and choose Edit Volume Settings from the Action (gear) pop-up
menu.
3 Set or clear the checkbox next to Spotlight and click OK.
60 Chapter 4 Managing SAN Storage