Pay Per Use Overview

Two types of PPU metrics can be used for billing purposes. PPU can either be based on the percent utilization of the CPUs or on the number of active CPUs. When the percent utilization method is used, all CPUs are active. The PPU software tracks the utilization of the CPUs and the monthly lease payment reflects the actual level of use. In contrast, the active CPU method bases the monthly lease payment on the number of active CPUs, not the utilization of those CPUs. Like Instant Capacity and Temporary Instant Capacity, when more CPU resources are required, they can be instantly activated. When the resources are no longer needed, they can be deactivated. In both the percent utilization and active CPU methods of reporting, the PPU software tracks the amount of CPU resources consumed and reports the utilization to the HP utility meter.

The HP utility meter is a hardware system that is configured by an HP service representative. The meter must have connectivity to the Internet and HP servers. One utility meter can collect usage data for a maximum of approximately 100 partitions or storage devices. From a PPU administration perspective, the only piece of information the HP utility meter needs is the hostname or IP address. There are no administration tasks that must be performed on the HP utility meter after the meter has been initially set up and configured.

A common concern when customers consider using PPU is the possibility that the lease payment will be much higher than expected due to unforeseen peaks in workload demands. In order to prevent unexpected leaps in resource utilization and the associated costs, PPU allows the system to be configured with CPU capping. When a customer uses CPU capping, the maximum number of CPUs that can be active on each partition is fixed. This results in a hard upper boundary on the amount of resources that can be consumed, thus ensuring the payment is within a bounded range.

Pay per use is supported on HP 9000 and HP Integrity nPartition servers running either HP-UX or Microsoft Windows operating systems. The Pay per use solution has the following requirements that must be met for each partition in the complex.

• PPU software must be installed on every partition. This includes installing the software on every HP Virtual Partition running within nPartitions.

• PPU software must have network connectivity to the PPU utility meter.

• PPU software must be configured to communicate with the PPU utility meter.

The following example scenario walks through the process of ensuring that these requirements are met for an HP-UX nPartition participating in PPU. It also describes the initial steps of configuring a Microsoft Windows nPartition for PPU.