HP-UX Virtual Partitions Administrator Guide (includes A.05.08) (5900-1312, March 2011)

CAUTION: Normally, ranges are granule-aligned (in other words, the starting address and the
ending address of the range is a multiple of a granule). However, due to memory fragmentation,
some of the ranges may not be granule-aligned. It is not recommended to assign such nongranule-
aligned ranges as user-specified ranges (mem:::base:range). Further, future vPars releases may
not support specifying ranges that are not aligned to a granule and may return an error when such
ranges are assigned to a virtual partition.
NOTE:
• Specifying an address range does not increase the amount of memory assigned to the partition.
Rather, it only specifies addresses to use for the already allocated memory sizes.
Therefore, all specified ranges cannot exceed the total allocated memory for the virtual partition.
In other words, the sum of the ILM- or CLM-specified ranges cannot exceed the total amount
of ILM or CLM memory reserved for the virtual partition.
• (vPars A.04.xx) Address ranges are unique within a given virtual partition. Therefore, specifying
base:range (and not a cell_ID) is sufficient for using an address range within CLM. You can
use vparstatus -A to list the available ranges and whether the ranges are a part of ILM
or CLM. Further, if the range is within CLM, vparstatus -Aalso lists to which cell the range
belongs.
2 GB Restriction (PA-RISC only)
When ranges are specified for the entire memory owned by a partition, you should ensure that at
least one of the ranges is below 2 GB and is large enough to accommodate the kernel for that
partition. However, other partitions also require memory below 2 GB for their kernels. Hence, you
also should ensure that the specified range below 2 GB is not so large such as to preclude memory
below 2 GB for the other partitions.
In general terms, the sum of the size of the kernels must be < 2 GB. To calculate the kernel sizes,
see “Calculating the Size of Kernels in Memory (PA-RISC only)” (page 286).
CAUTION: Not allowing enough memory for the other partitions will cause the other partitions
to not boot. You can boot the partition by freeing up enough memory for the partition to boot, such
as by shutting down an active partition.
If no memory ranges are below 2 GBs for a given partition, the partition will not boot.
If you use the defaults of the dynamic tunables, you will not run into the 2 GB limit. However, if
you have adjusted the dynamic tunables, it is possible to run beyond the 2 GB boundary. For more
information on adjusting the kernel size with dynamic tunables, go to the BSC website at
www.hp.com/go/hpux-networking-docs, click HP-UX 11i v3 Networking Software and see the
white paper Managing NFS and KRPC Kernel Configurations in HP-UX 11i v3.
Memory: Granularity Concepts
Granularity refers to the unit size in which memory is assigned to all virtual partitions in a given
vPars database (vpdb). Granularity reflects only the unit size of memory and not the amount of
memory that is assigned.
This section briefly covers configuring memory granularity.
The default granularity is 128 MB for ILM and 128 MB for CLM. However, you can specify your
own granularity for CLM and/or ILM. Granularity has some specific restrictions and cannot be
changed in a vPars database after they are set. Be sure to read the CAUTION portion in the next
section.
Memory: Granularity Concepts 211