alluxio.client.metrics

Class MetricsHeartbeatContext

java.lang.Object

alluxio.client.metrics.MetricsHeartbeatContext

@ThreadSafe
public class MetricsHeartbeatContext
extends Object

A class used to track metrics heartbeats to a master. The class should be instantiated when a new FileSystemContext is created with a configuration that points to a given master. As new FileSystemContexts are created, if they utilize the same connection details, then they can simply be added to this context so that their information is included in the metrics heartbeat. To add them, one should simply call addHeartbeat(ClientContext, MasterInquireClient) with the necessary arguments. For each separate set of connection details, a new instance of this class is created. As FileSystemContexts are closed, they remove themselves from the internal metrics heartbeat. When a context reaches 0 tracked contexts it will automatically close and remove itself from the internal MASTER_METRICS_HEARTBEAT map. When the final FileSystemContext closes and removes its heartbeat from metrics it will also shutdown and close the executor service until a new FileSystemContext is created.

Method Summary

Modifier and Type	Method and Description
static void	addHeartbeat(ClientContext ctx, MasterInquireClient inquireClient) Sets up a new metrics heartbeat with the given client information.
static void	removeHeartbeat(ClientContext ctx) Removes an application from the metrics heartbeat.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

addHeartbeat

public static void addHeartbeat(ClientContext ctx,
                                MasterInquireClient inquireClient)

Sets up a new metrics heartbeat with the given client information. This will instantiate a new executor service if it is the first heartbeat to be added, otherwise the application Id is simply included in an already existing heartbeat. This helps to consolidate RPCs and utilize less resources on the client.

Parameters:

ctx - The application's client context

inquireClient - the master inquire client used to connect to the master

removeHeartbeat

public static void removeHeartbeat(ClientContext ctx)

Removes an application from the metrics heartbeat. If this is the last application to be removed for a given master then it will cancel the execution of the metrics RPC for that master. If this is the last application to be removed for the whole JVM, it will shutdown the executor threadpool until another application needs to heartbeat. If the appId which is to be removed isn't found, the application will silently continue.

Parameters:

ctx - The client context used to register the heartbeat