IceStorm Metrics

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You can monitor IceStorm using the Administrative Facility and the Metrics Facet. IceStorm provides two metrics class to monitor topic and subscriber related metrics. These classes are defined in IceStorm/Metrics.ice and are shown below.

Slice

module IceMX
{
    class TopicMetrics extends Metrics
    {
        long published = 0;
        long forwarded = 0;
    }
    class SubscriberMetrics extends Metrics
    {
        int queued = 0;
        int outstanding = 0;
        long delivered = 0;
    }
}

These classes provide the following metrics:

Metric	Description
`published`	The number of events that publishers sent to the topic.
`forwarded`	The number of events the topic received from linked topics.
`queued`	The number of events IceStorm queued for the subscriber and has not started sending yet.
`outstanding`	The number of events IceStorm started sending to the subscriber and whose delivery has not completed.
`delivered`	The number of events whose delivery completed: IceStorm counts an event as delivered when it receives the reply for a twoway subscriber or a topic link, and when it has sent the request for a oneway, datagram or batch subscriber.

IceStorm records metrics in the metrics map described below.

Metrics map name	Slice class	Description	Property prefix
Topic	`IceMX::TopicMetrics`	Topic metrics	`IceMX.Metrics.view-name.Map.Topic`
Subscriber	`IceMX::SubscriberMetrics`	Subscriber metrics	`IceMX.Metrics.view-name.Map.Subscriber`

To configure a metrics view to record IceStorm topic and subscriber you can use for example:

IceMX.Metrics.IceStormView.Map.Topic.GroupBy=id
IceMX.Metrics.IceStormView.Map.Subscriber.GroupBy=id

This will configure a view containing only the Topic and Subscriber maps, with one metrics object per topic and one metrics object per subscriber. The id of a subscriber is its stringified proxy, so a subscriber that subscribes to several topics with identical proxies gets a single metrics object for all these topics; use IceMX.Metrics.IceStormView.Map.Subscriber.GroupBy=topic,id to get one metrics object per subscription.

You can use the following attributes when configuring the IceStorm Topic map:

Name	Description
id	The topic name.
parent	The string `IceStorm`.
none	The empty string.
topic	The topic name.
service	The string `IceStorm`.

The Subscriber map can be configured with the following attributes:

Name	Description
id	The stringified proxy of the subscriber.
parent	The name of the topic to which this subscriber belongs.
none	The empty string.
topic	The name of the topic to which this subscriber belongs.
service	The string `IceStorm`.
identity	The identity of the subscriber proxy.
facet	The facet of the subscriber proxy.
encoding	The encoding of the subscriber proxy.
mode	The mode of the subscriber proxy: `twoway`, `oneway`, `batch-oneway`, `datagram`, or `batch-datagram`.
proxy	The subscriber proxy.
link	The proxy of the topic linked to the topic which owns this subscriber.
state	The state of the subscriber. It can either be "online", "offline" or "error".
`qos.<name>`	The value of the `<name>` entry in the subscriber's QoS, or `default` if the QoS has no such entry.

For example, IceMX.Metrics.IceStormView.Map.Subscriber.GroupBy=qos.reliability groups subscribers by the value of their reliability QoS.

See Also