The nova.compute.monitors.base Module

class CPUMonitorBase(compute_manager)

Bases: nova.compute.monitors.base.MonitorBase

Base class for all monitors that return CPU-related metrics.

get_metric_names()

class MonitorBase(compute_manager)

Bases: object

Base class for all resource monitor plugins.

A monitor is responsible for adding a set of related metrics to a nova.objects.MonitorMetricList object after the monitor has performed some sampling or monitoring action.

add_metrics_to_list(metrics_list)

Adds metric objects to a supplied list object.

Parameters:metric_list – nova.objects.MonitorMetricList that the monitor plugin should append nova.objects.MonitorMetric objects to.

get_metric_names()

Get available metric names.

Get available metric names, which are represented by a set of keys that can be used to check conflicts and duplications

Returns:set containing one or more values from :py:attr: nova.objects.fields.MonitorMetricType.ALL

get_metrics()

Returns a list of tuples containing information for all metrics tracked by the monitor.

Note that if the monitor class is responsible for tracking a related set of metrics – e.g. a set of percentages of CPU time allocated to user, kernel, and idle – it is the responsibility of the monitor implementation to do a single sampling call to the underlying monitor to ensure that related metric values make logical sense.

Returns:list of (metric_name, value, timestamp) tuples