Add Support for HPM Performance Policy Metrics in KVM for IBM z Systems

KVM for IBM z Systems provides open source virtualization for Linux workloads
running on the IBM mainframe (AKA System z). HPM (Hypervisor Performnace
Management) component of KVM for IBM z Systems provides capability for policy
based, goal-oriented monitoring and management of virtual server CPU resources.

This blueprint proposes a new Ceilometer Pollster plugin similar to existing
CPU and disk pollsters to obtain performance policy level metrics from HPM
component of KVM for IBM z Systems.

Background
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The HPM's monitoring and management actions are in the context of workloads.
A workload is a collection of virtual server instances that perform a
particular business function. The workload has a performance policy
associated with it. The policy consists of a set of service classes, each of
which has a business importance level, a goal, and a set of classification
rules defined for it. (A service class is a grouping of a set of virtual
servers performing a similar task, like a set of, say, WEB servers.)

Issue
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In a KVM for IBM z Openstack environment with HPM component actively managing
the virtual servers according to performance policy and goals, there are
situations where a cloud administrator should be able to monitor the
performance of workloads and should have the capability to drill-down into the
metrics to understand performance bottlenecks.

Currently there is no way to obtain and utilize these performance metrics from
HPM component of KVM for IBM z Systems in an Openstack environment.

Use Cases
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As a cloud administrator who wants to run KVM for IBM z Systems with HPM
component at high utilization while ensuring important workloads get
sufficient CPU resources to perform well, I would like to monitor the
performance of workloads (cluster of virtual servers) and have the capability
to drill-down into the metrics to understand the performance bottlenecks.

References:
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* KVM for IBM z Systems -
http://www-01.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/1/897/ENUS215-261/index.html&lang=en&request_locale=en

* Hypervisor Performance Management (HPM) –
http://www.ibm.com/support/knowledgecenter/SSNW54_1.1.1/com.ibm.kvm.v111.admin/part2.htm?lang=en