194 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
Figure 6-4   Create Pool dialog box
Mark the Data Reduction check box to create the Data Reduction Pool. Leaving it unmarked 
creates a standard storage pool.
A standard storage pool that is created by using the GUI has a default extent size of 1 GB. 
Data Reduction Pools have a default extent size of 4 GB. The size of the extent is selected at 
creation time and cannot be changed later. 
If you want to specify a different extent size, you can enable this option by clicking Settings → 
GUI Preferences → General and checking Advanced pool settings, as shown in 
Figure 6-5.
Figure 6-5   Advanced pool settings
When advanced pool settings are enabled, you can additionally select an extent size at 
creation time, as shown in Figure 6-6 on page 195.