JarCasting
Aether
Monitoring for the Aeron messaging system.
Usage
An instance of the Aether client reads counters from one or more Aeron MediaDrivers, and publishes the counter data to a collector. The collector's function is to build a system-wide view of the Aeron message flows, matching publishers to subscribers.
Running an Aether Collector
// launch a MediaDriver for publishing counters
final MediaDriver driver = MediaDriver.launchEmbedded(new MediaDriver.Context()
.threadingMode(ThreadingMode.SHARED)
.sharedIdleStrategy(new SleepingMillisIdleStrategy(1L)));
// create a publish that will send out counter snapshots
final CounterSnapshotPublisher snapshotPublisher = new CounterSnapshotPublisher(
new CounterSnapshotPublisher.Context()
.aeronDirectoryName(driver.aeronDirectoryName()));
// create an Aether agent that will periodically read and publish the counters
final Aether aether = Aether.launch(new Aether.Context()
.monitoringLocations(Collections.singletonList(
new Aether.MonitoringLocation("default", "/path/to/monitored-media-driver")))
.counterSnapshotListener(snapshotPublisher)
.aeronDirectoryName(driver.aeronDirectoryName())
.threadingMode(Aether.ThreadingMode.THREADED));
Running an Aether Aggregator
// create a MediaDriver to receive counter snapshots
final MediaDriver mediaDriver = MediaDriver.launchEmbedded(new MediaDriver.Context()
.threadingMode(ThreadingMode.SHARED)
.sharedIdleStrategy(new SleepingMillisIdleStrategy(1L)));
// create a subscription to deserialise received snapshots
final CounterSnapshotSubscriber counterSnapshotSubscriber =
new CounterSnapshotSubscriber(new CounterSnapshotSubscriber.Context()
.aeronDirectoryName(mediaDriver.aeronDirectoryName())
.counterSnapshotListener(new ConsolePrinter()));
// poll subscription to update system snapshot
counterSnapshotSubscriber.doWork();
Output
The default ConsolePrinter will display aggregate information for all configured contexts:
-----------------------------------------
===== System counters for "server" =====
Bytes sent: 0
Bytes received: 27584
NAKs sent: 0
NAKs received: 0
Errors: 0
Client timeouts: 0
===== System counters for "client" =====
Bytes sent: 27584
Bytes received: 0
NAKs sent: 0
NAKs received: 0
Errors: 0
Client timeouts: 0
===== Monitoring 3 channels =====
==== aeron:udp?endpoint=localhost:54567/37 ====
---- Publisher Session 2033564099 ----
| publisher position: 19584
| publisher limit: 26240
| sender position: 26240
| sender limit: 133440
---- Subscriber ----
| receiver position: 26240
| receiver HWM: 26240
| position (1): 3520
| position (2): 2432
| position (3): 2368
-----------------------------------------
==== aeron:udp?endpoint=localhost:54587/37 ====
---- Publisher Session 2033564101 ----
| publisher position: 320
| publisher limit: 576
| sender position: 576
| sender limit: 131264
---- Subscriber ----
| receiver position: 576
| receiver HWM: 576
| position (6): 192
-----------------------------------------
As an Application
Collector
To run Aether as a command-line application, runtime configuration can be used:
aether-collector.properties
# Describes the locations of MediaDrivers that should be monitored
aether.monitoringLocations=client:/path/to/client/media-driver;server:/path/to/server/media-driver
# Tells Aether to publish snapshot over an Aeron Publication
aether.transport=AERON
# Tells Aether to monitor locations and publish
aether.mode=PUBLISHER
# Describes the location where Aether should launch its own MediaDriver for publishing
aeron.dir=/path/to/aether-publisher-media-driver
# Describe the endpoint to publish data to
aether.transport.channel=aeron:udp?endpoint=monitoring-host:18996
Then run the collector:
java -cp /path/to/aeron-driver.jar:/path/to/aether.jar \
com.aitusoftware.aether.Aether /path/to/aether-collector.properties
Aggregator
aether-aggregator.properties
# Tells Aether to receive snapshot over an Aeron Publication
aether.transport=AERON
# Tells Aether to subscribe to events
aether.mode=SUBSCRIBER
# Describes the location where Aether should launch its own MediaDriver for subscribing
aeron.dir=/path/to/aether-subscriber-media-driver
# Describe the endpoint to receive data on
aether.transport.channel=aeron:udp?endpoint=monitoring-host:18996
Then run the aggregator:
java -cp /path/to/aeron-driver.jar:/path/to/aether.jar \
com.aitusoftware.aether.Aether /path/to/aether-aggregator.properties
Visualising snapshot data
Aether-Net provides a simple UI to display the counter snapshots.
