vparresources.5 (2010 09)

v
vparresources(5) vparresources(5)
when the vPar is Up. If size is not an integral multiple of the granularity of the specified memory type,
vPars normally adjusts it upward to the next granule boundary. However, vPars will allow you to
configure a sub-granular quantity of memory if doing so exhausts available memory. Consider a
configuration with 4 GB granules and two granules of unassigned memory. Due to fragmentation, 2 GB
of one granule are not available. The monitor will allow you to assign either 4 GB (one granule) or 6 GB
(all remaining memory).
In a vPar environment, either of the above command line options cause the monitor to reserve the indi-
cated memory, if it is available. However, actual memory ranges are only assigned to the vPar when it is
booted. These ranges may be different from boot to boot.
Changes to memory size specifications can be made when a vPar is
Up or Down or when it is in an alter-
nate database. If changes are made when the vPar is
Up and if the b[ase]| f[loat
[ing]] attribute is
not specified, the memory is added as base memory. Base memory cannot be deleted when the vPar is
Up. If the memory is added as "floating" memory, it can be deleted even when the vPar is
Up. If the
memory is added when the vPar is
Up, the operation may not complete immediately. In such cases, the
vparstatus -v output will display the tag
(pendingmigration).
In a non-vPar environment, or when configuring an alternate database, existence of the specified memory
(including the cell for CLM) cannot be verified. The specification is placed in the database as a
Requested entry. When the database is loaded into the monitor, the monitor may adjust the specified
amounts to correspond to existing memory resources. If sufficient resources cannot be found, the monitor
may not boot the vPar.
Assigning Memory Ranges - Live Database
The
vparstatus -A command displays actual available memory ranges. Ranges that are lost to frag-
mentation are not shown.
You can assign specific memory address ranges to your vPar, but Hewlett-Packard recommends that you
not do this except when required for performance reasons.
• If the target vPar is Down, assigning a range does not change the total memory allocation. It simply
reserves a specific address range within that allocation. Therefore, you must first allocate an amount
of memory, and then assign ranges.
• If the target vPar is Up, adding a range will increase the total memory allocation of that type. There-
fore, it is not necessary to first allocate the amount of memory. However, the amount of memory
required from the type for the range should be available and free in the monitor. Sometimes, the
operation may not complete immediately. In such cases, the
vparstatus -v output will display the
tag (pending migration).
• A specific address range is unique on the system, and so may be a part of ILM or CLM. You cannot
tell from the address alone if it is ILM or CLM. Therefore, you always use the
vparstatus -A com-
mand to list all available memory ranges and their type before attempting to assign a specific range.
If you do not need specific memory ranges, configure only amounts of memory and allow the monitor to
manage the assignment of specific ranges.
NOTE: On PA, memory below 2GB is used for loading and launching kernel of each partition. Kernel
requires memory where it is loaded to be base memory. Hence, a partition should not contain any user-
specified floating ranges below 2GB. If a partition has a user-specified floating range below 2GB, the
monitor will not boot the partition until the user removes the floating range. If needed, the range can be
added back as a user-specified base range.
NOTE: The kernel requires some amount of base memory to boot and run. Typically, the kernel expects
the low end of the memory to be base memory. To satisfy this expectation, the monitor-assigned base
memory ranges are at low end during boot. If the virtual partition has less overall base memory or less
base memory at the low end, some of the floating memory gets converted to base memory during boot. If
the floating memory range that got converted to base memory happens to fall within a user-specified float-
ing range, the range is converted from user-specified to the monitor-assigned range.
If a memory range specification (either base or range) is not granule- aligned, but you have specified the
entire range, the monitor does not allow you to assign it. If you do not specify the entire range, the moni-
tor lowers the base as required to the base of the available range or to the next lower granule boundary,
whichever is reached first. The monitor increases the range as required, starting from the original end-
point, to the end of the available range or the next higher granule boundary, whichever is reached first.
If the monitor is able to assign this modified range, you will get a warning that your request has been
modified. If the increased memory range cannot be assigned, for example because it exceeds the total
8 Hewlett-Packard Company − 8 − HP-UX 11i Version 3: September 2010