HP Integrity Virtual Machines functions

HP Integrity Virtual Machines provides a sub-CPU partitioning capability that dynamically partitions a processor resource into 5% units and then allocates the units to logical partitions. By using this function, you can set a maximum of 20 logical processors for one physical processor. When this function is used, PFM - Agent for Platform collects performance data for the logically partitioned processors.

In addition to processor resources, HP Integrity Virtual Machines supports sharing of I/O by multiple logical partitions and supports memory virtualization. Because HP Integrity Virtual Machines supports Linux as well as HP-UX, Linux compatibility is also provided.

HP Integrity Virtual Machines structure

The processor resource allocation function provided by HP Integrity Virtual Machines is almost the same as the Micro-Partitioning function provided by AIX.

Figure 2-12 HP Integrity Virtual Machines structure

Using PFM - Agent for Platform on HP Integrity Virtual Machines

When using PFM - Agent for Platform on HP Integrity Virtual Machines, note that the information about processors, memory, and devices is changed.

Processor information

A record that indicates processor information displays the same number of instances as the number of virtual processors allocated to the virtual machine.

Because the resources allocated to the virtual processor on HP Integrity Virtual Machines change dynamically, the amount of resources that is actually used differs even when the processor usage is the same. For example, 30% of the processor resources might be allocated to processor #1 whose usage is 50%. If the allocation ratio changes to 60%, the usage of processor #1 becomes 25% (in actuality, there is a margin of error due to overhead and the kernel structure). Accordingly, to determine whether the processor usage is low, you should use fields that are unlikely to be affected by processor resource allocation, such as the current queue length.

Memory

Although HP Integrity Virtual Machines supports memory virtualization, virtualized memory cannot be changed dynamically. Accordingly, operation can proceed on a virtual machine the same way as on a non-virtual machine.

Devices

As with memory, HP Integrity Virtual Machines supports I/O virtualization. Disk performance data is only collected for logical partition groups. System-wide performance data cannot be collected.