For a quick-start guide to VVOLs, see  Quick-start Guide to Configuring VMware Virtual  Volumes for Systems Powered by IBM Spectrum Virtualize , REDP-5321. In addition, see  Configuring VMware Virtual Volumes for Systems Powered by IBM Spectrum  Virtualize , SG24-8328. Use this option to change memory limits for Copy Services and RAID functions per I/O group. Copy Services features and RAID require that small amounts of volume cache be converted  from cache memory into bitmap memory to allow the functions to operate. If you do not have  enough bitmap space allocated when you try to use one of the functions, you will not be able  to complete the configuration.  The total memory that can be dedicated to these functions is not defined by the physical  memory in the system. The memory is constrained by the software functions that use the  memory. These settings are available from  Settings  System  Resources , as shown in  Figure 5-66. Figure 5-65 Enabling VVOLs management Figure 5-66 Resources allocation 194  Implementing the IBM System Storage SAN Volume Controller with IBM Spectrum Virtualize V8.2.1 Resources