Configuring and Migrating Memory on vPars

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2. Find out the available amount of memory in each locality using the vparstatus (-A option)
output. The amount selected from each locality to add should be less than or equal to this
available amount.
Monitoring the Status of an Online Operation
The vparstatus command output (-v option) shows the status of the last initiated CPU or memory
migration operation. In the vparstatus output, this shows up under the section called ”OL* Details”.
A sample output is shown below:
[OL* Details]
Sequence ID: 123
Operation: Memory Addition
Status: PASS
In the above output, the sequence ID is a number used to uniquely identify the memory migration (or
CPU migration) operation that was last initiated on a given partition. The operation field indicates
what type of online migration event was initiated, and the status field indicates the current state of the
operation. The status field may contain PASS, PENDING, ABORT or FAIL. The pending status
indicates that the operation is in progress. If the status shows ABORT or FAIL, this means the online
memory (or CPU) migration has failed. When this happens, there are three main logs that the system
administrator may consult to determine what exactly prevented the operation from completing
successfully: the EVM event log (evmget | evmshow), the operating system log
(/var/adm/syslog/syslog.log) and the vPars monitor log (vparextract –l).
Cancelling an Online Operation
Memory migration, and in particular the memory delete operation, could sometimes take a long time
to complete. This is because for the memory delete operation, the kernel has to first evacuate the
contents of the memory pages that are in use by applications. Depending on the size of the memory
being deleted, its usage and the amount of memory that is free, this operation could end up taking
considerable time. The vparmodify command contains an option to allow the user to cancel an
ongoing CPU or memory migration. The option (-C sequenceid) will allow the user to cancel
individual pending CPU or memory OL* operations on a per partition basis using the sequence
identifier for the operation. The operation can be cancelled under two conditions: the operation is still
in the PENDING state and the operating system has not committed to the operation. The status of the
operation can be determined using output of the vparstatus –v command. The progress of the
operation can be determined using the output of the evmget | evmshow command or evmget –A
command from within the partition being modified.
Memory Migration Example
This section illustrates the usage of commands and tools through a memory migration example. The
memory migration operation is demonstrated as follows:
1. Describe the experimental setup.
2. Describe memory usage on vpar1 that has 1 GB of free memory.
3. Describe memory usage on vpar2 that uses all memory.
4. Describe memory usage on vpar1 after online deletion of 1 GB of memory.
5. Describe memory usage on vpar2 after online addition of 1 GB of memory.