Adding memory (dynamically addable memory)

Up to 4GB of general purpose (GP or pageable) memory and up to 64GB of dedicated (Identity Free or IDF) memory can be added dynamically and configured without shutting down and rebooting the system. The amount of general purpose memory that can be added dynamically can also be autotuned based on the amount of total kernel virtual memory and total physical memory.

When new memory is added to the system (and during inital system installation), the newly added memory is detected by the hardware. The hardware driver (supplied by the hardware vendor) then calls a function in the mem(HW) driver, which configures the new memory according to the following policy:

• If the tunable parameter DEDICATED_MEMORY (See ``Virtual memory (VM) parameters'') is set to a non-zero value, then new memory is configured as dedicated memory until the DEDICATED_MEMORY limit is reached.

• If DEDICATED_MEMORY is set to ``0'', or if the amount of memory configured as dedicated memory has already reached the DEDICATED_MEMORY limit, then new memory is configured as general purpose memory.

Memory must be dynamically added in multiples of 32MB. The total amount of memory you can add dynamically to your system is limited by:

• The addressability of the processor. If the processor does not support the Physical Address Extension (PAE) feature, then the limit is 4GB. Otherwise, the limit is 64GB.

• The memory license limit. You must have sufficient licenses installed for the memory you are adding. See Licensing software for an overview of licensing software.

Note that dynamic removal of memory is not supported.