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Example 11 with UriProperties

use of com.linkedin.d2.balancer.properties.UriProperties in project rest.li by linkedin.

the class ZKFSTogglingLoadBalancerFactoryImpl method createLoadBalancer.

@Override
public TogglingLoadBalancer createLoadBalancer(ZKConnection zkConnection, ScheduledExecutorService executorService) {
    _log.info("Using d2ServicePath: " + _d2ServicePath);
    ZooKeeperPermanentStore<ClusterProperties> zkClusterRegistry = createPermanentStore(zkConnection, ZKFSUtil.clusterPath(_baseZKPath), new ClusterPropertiesJsonSerializer());
    ZooKeeperPermanentStore<ServiceProperties> zkServiceRegistry = createPermanentStore(zkConnection, ZKFSUtil.servicePath(_baseZKPath, _d2ServicePath), new ServicePropertiesJsonSerializer());
    ZooKeeperEphemeralStore<UriProperties> zkUriRegistry = createEphemeralStore(zkConnection, ZKFSUtil.uriPath(_baseZKPath), new UriPropertiesJsonSerializer(), new UriPropertiesMerger(), _useNewEphemeralStoreWatcher);
    FileStore<ClusterProperties> fsClusterStore = createFileStore("clusters", new ClusterPropertiesJsonSerializer());
    FileStore<ServiceProperties> fsServiceStore = createFileStore(_d2ServicePath, new ServicePropertiesJsonSerializer());
    FileStore<UriProperties> fsUriStore = createFileStore("uris", new UriPropertiesJsonSerializer());
    PropertyEventBus<ClusterProperties> clusterBus = new PropertyEventBusImpl<ClusterProperties>(executorService);
    PropertyEventBus<ServiceProperties> serviceBus = new PropertyEventBusImpl<ServiceProperties>(executorService);
    PropertyEventBus<UriProperties> uriBus = new PropertyEventBusImpl<UriProperties>(executorService);
    // This ensures the filesystem store receives the events from the event bus so that
    // it can keep a local backup.
    clusterBus.register(fsClusterStore);
    serviceBus.register(fsServiceStore);
    uriBus.register(fsUriStore);
    TogglingPublisher<ClusterProperties> clusterToggle = _factory.createClusterToggle(zkClusterRegistry, fsClusterStore, clusterBus);
    TogglingPublisher<ServiceProperties> serviceToggle = _factory.createServiceToggle(zkServiceRegistry, fsServiceStore, serviceBus);
    TogglingPublisher<UriProperties> uriToggle = _factory.createUriToggle(zkUriRegistry, fsUriStore, uriBus);
    SimpleLoadBalancerState state = new SimpleLoadBalancerState(executorService, uriBus, clusterBus, serviceBus, _clientFactories, _loadBalancerStrategyFactories, _sslContext, _sslParameters, _isSSLEnabled, _clientServicesConfig);
    SimpleLoadBalancer balancer = new SimpleLoadBalancer(state, _lbTimeout, _lbTimeoutUnit);
    TogglingLoadBalancer togLB = _factory.createBalancer(balancer, state, clusterToggle, serviceToggle, uriToggle);
    togLB.start(new Callback<None>() {

        @Override
        public void onError(Throwable e) {
            _log.warn("Failed to run start on the TogglingLoadBalancer, may not have registered " + "SimpleLoadBalancer and State with JMX.");
        }

        @Override
        public void onSuccess(None result) {
            _log.info("Registered SimpleLoadBalancer and State with JMX.");
        }
    });
    return togLB;
}
Also used : ServicePropertiesJsonSerializer(com.linkedin.d2.balancer.properties.ServicePropertiesJsonSerializer) UriPropertiesMerger(com.linkedin.d2.balancer.properties.UriPropertiesMerger) TogglingLoadBalancer(com.linkedin.d2.balancer.util.TogglingLoadBalancer) UriPropertiesJsonSerializer(com.linkedin.d2.balancer.properties.UriPropertiesJsonSerializer) ClusterPropertiesJsonSerializer(com.linkedin.d2.balancer.properties.ClusterPropertiesJsonSerializer) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) SimpleLoadBalancerState(com.linkedin.d2.balancer.simple.SimpleLoadBalancerState) SimpleLoadBalancer(com.linkedin.d2.balancer.simple.SimpleLoadBalancer) ServiceProperties(com.linkedin.d2.balancer.properties.ServiceProperties) PropertyEventBusImpl(com.linkedin.d2.discovery.event.PropertyEventBusImpl) ClusterProperties(com.linkedin.d2.balancer.properties.ClusterProperties) None(com.linkedin.common.util.None)

Example 12 with UriProperties

use of com.linkedin.d2.balancer.properties.UriProperties in project rest.li by linkedin.

the class LoadBalancerTestState method getUriProperties.

@Override
public LoadBalancerStateItem<UriProperties> getUriProperties(String clusterName) {
    try {
        URI uri1 = URI.create("http://test.qa1.com:1234");
        URI uri2 = URI.create("http://test.qa2.com:2345");
        URI uri3 = URI.create("http://test.qa3.com:6789");
        Map<Integer, PartitionData> partitionData = new HashMap<Integer, PartitionData>(1);
        partitionData.put(DefaultPartitionAccessor.DEFAULT_PARTITION_ID, new PartitionData(1d));
        Map<URI, Map<Integer, PartitionData>> uriData = new HashMap<URI, Map<Integer, PartitionData>>(3);
        uriData.put(uri1, partitionData);
        uriData.put(uri2, partitionData);
        uriData.put(uri3, partitionData);
        return (getUriProperties) ? new LoadBalancerStateItem<UriProperties>(new UriProperties("cluster-1", uriData), 0, 0) : null;
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}
Also used : HashMap(java.util.HashMap) PartitionData(com.linkedin.d2.balancer.properties.PartitionData) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) URI(java.net.URI) HashMap(java.util.HashMap) Map(java.util.Map)

Example 13 with UriProperties

use of com.linkedin.d2.balancer.properties.UriProperties in project rest.li by linkedin.

the class SimpleLoadBalancerDelayTest method testLoadBalancerWithSlowStartClient.

@Test(groups = { "small", "back-end" }, enabled = false)
public void testLoadBalancerWithSlowStartClient() throws Exception {
    // Generate service, cluster and uri properties for d2
    URI uri1 = URI.create("http://test.qa1.com:1234");
    URI uri2 = URI.create("http://test.qa2.com:2345");
    URI uri3 = URI.create("http://test.qa3.com:6789");
    String clusterName = "cluster-2";
    Map<Integer, PartitionData> partitionData = new HashMap<>(1);
    partitionData.put(DefaultPartitionAccessor.DEFAULT_PARTITION_ID, new PartitionData(1d));
    Map<URI, Map<Integer, PartitionData>> uriData = new HashMap<>(3);
    uriData.put(uri1, partitionData);
    uriData.put(uri2, partitionData);
    uriData.put(uri3, partitionData);
    ClusterProperties clusterProperties = new ClusterProperties(clusterName);
    List<String> prioritizedSchemes = Collections.singletonList("http");
    // enable multi-probe consistent hashing
    Map<String, Object> lbStrategyProperties = Collections.singletonMap(PropertyKeys.HTTP_LB_CONSISTENT_HASH_ALGORITHM, DegraderRingFactory.MULTI_PROBE_CONSISTENT_HASH);
    // set initial drop rate and slow start threshold
    Map<String, String> degraderProperties = new HashMap<>();
    degraderProperties.put(PropertyKeys.DEGRADER_INITIAL_DROP_RATE, "0.99");
    degraderProperties.put(PropertyKeys.DEGRADER_SLOW_START_THRESHOLD, "0.1");
    // constant delay generator
    LoadBalancerSimulator.TimedValueGenerator<String> delayGenerator = (uri, time, unit) -> 100l;
    // constant QPS generator
    LoadBalancerSimulator.QPSGenerator qpsGenerator = () -> 1000;
    Map<String, Object> transportClientProperties = Collections.singletonMap("DelayGenerator", delayGenerator);
    ServiceProperties serviceProperties = new ServiceProperties("foo", clusterName, "/foo", Arrays.asList("degrader"), lbStrategyProperties, transportClientProperties, degraderProperties, prioritizedSchemes, null);
    UriProperties uriProperties = new UriProperties(clusterName, uriData);
    // pass all the info to the simulator
    LoadBalancerSimulator loadBalancerSimulator = new LoadBalancerSimulator(serviceProperties, clusterProperties, uriProperties, delayGenerator, qpsGenerator);
    // Start the simulation, wait for 10 UPDATE_INTERVALS to make sure all uris are fully ramped.
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 20);
    printStates(loadBalancerSimulator);
    URI uri4 = URI.create("http://test.qa4.com:9876");
    uriData.put(uri4, partitionData);
    uriProperties = new UriProperties(clusterName, uriData);
    loadBalancerSimulator.updateUriProperties(uriProperties);
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS);
    printStates(loadBalancerSimulator);
    // Create the delay generator for the uris
    URI expectedUri4 = URI.create("http://test.qa4.com:9876/foo");
    loadBalancerSimulator.getCountPercent(expectedUri4);
    // the points for uri4 should be 1 and call count percentage is 0.3%.
    double callCountPercent = loadBalancerSimulator.getCountPercent(expectedUri4);
    assertTrue(callCountPercent <= 0.006, "expected percentage is less than 0.006, actual is " + callCountPercent);
    // wait for 2 intervals due to call dropping
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri4 should be 4 and call count percentage is 1.3%
    callCountPercent = loadBalancerSimulator.getCountPercent(expectedUri4);
    assertTrue(callCountPercent <= 0.02, "expected percentage is less than 0.02, actual is " + callCountPercent);
    // wait for 2 intervals due to call dropping
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri4 should be 16 and call count percentage is 5%
    callCountPercent = loadBalancerSimulator.getCountPercent(expectedUri4);
    assertTrue(callCountPercent <= 0.07, "expected percentage is less than 0.07, actual is " + callCountPercent);
    assertTrue(callCountPercent >= 0.03, "expected percentage is larger than 0.03, actual is " + callCountPercent);
    // wait for 2 intervals due to call dropping
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri4 should be 56 and call count percentage is 16%
    callCountPercent = loadBalancerSimulator.getCountPercent(expectedUri4);
    assertTrue(callCountPercent <= 0.18, "expected percentage is less than 0.18, actual is " + callCountPercent);
    assertTrue(callCountPercent >= 0.12, "expected percentage is larger than 0.12, actual is " + callCountPercent);
    // wait for 2 intervals due to call dropping
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri4 should be 96 and call count percentage is 24%
    callCountPercent = loadBalancerSimulator.getCountPercent(expectedUri4);
    assertTrue(callCountPercent <= 0.28, "expected percentage is less than 0.26, actual is " + callCountPercent);
    assertTrue(callCountPercent >= 0.20, "expected percentage is larger than 0.22, actual is " + callCountPercent);
}
Also used : DegraderLoadBalancerStrategyConfig(com.linkedin.d2.balancer.strategies.degrader.DegraderLoadBalancerStrategyConfig) DefaultPartitionAccessor(com.linkedin.d2.balancer.util.partitions.DefaultPartitionAccessor) Arrays(java.util.Arrays) ClusterProperties(com.linkedin.d2.balancer.properties.ClusterProperties) Logger(org.slf4j.Logger) Iterator(java.util.Iterator) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) LoggerFactory(org.slf4j.LoggerFactory) Assert.assertEquals(org.testng.Assert.assertEquals) HashMap(java.util.HashMap) Test(org.testng.annotations.Test) PropertyKeys(com.linkedin.d2.balancer.properties.PropertyKeys) ExecutionException(java.util.concurrent.ExecutionException) TimeUnit(java.util.concurrent.TimeUnit) List(java.util.List) DegraderRingFactory(com.linkedin.d2.balancer.strategies.degrader.DegraderRingFactory) Map(java.util.Map) Assert.assertTrue(org.testng.Assert.assertTrue) PartitionData(com.linkedin.d2.balancer.properties.PartitionData) URI(java.net.URI) ServiceProperties(com.linkedin.d2.balancer.properties.ServiceProperties) ServiceUnavailableException(com.linkedin.d2.balancer.ServiceUnavailableException) Collections(java.util.Collections) HashMap(java.util.HashMap) URI(java.net.URI) ServiceProperties(com.linkedin.d2.balancer.properties.ServiceProperties) PartitionData(com.linkedin.d2.balancer.properties.PartitionData) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) ClusterProperties(com.linkedin.d2.balancer.properties.ClusterProperties) HashMap(java.util.HashMap) Map(java.util.Map) Test(org.testng.annotations.Test)

Example 14 with UriProperties

use of com.linkedin.d2.balancer.properties.UriProperties in project rest.li by linkedin.

the class SimpleLoadBalancerDelayTest method testLoadBalancerWithDelay.

@Test(groups = { "small", "back-end" }, enabled = false)
public void testLoadBalancerWithDelay() throws Exception {
    // Generate service, cluster and uri properties for d2
    URI uri1 = URI.create("http://test.qa1.com:1234");
    URI uri2 = URI.create("http://test.qa2.com:2345");
    URI uri3 = URI.create("http://test.qa3.com:6789");
    Map<Integer, PartitionData> partitionData = new HashMap<Integer, PartitionData>(1);
    partitionData.put(DefaultPartitionAccessor.DEFAULT_PARTITION_ID, new PartitionData(1d));
    Map<URI, Map<Integer, PartitionData>> uriData = new HashMap<URI, Map<Integer, PartitionData>>(3);
    uriData.put(uri1, partitionData);
    uriData.put(uri2, partitionData);
    uriData.put(uri3, partitionData);
    ClusterProperties clusterProperties = new ClusterProperties("cluster-1");
    List<String> prioritizedSchemes = Collections.singletonList("http");
    ServiceProperties serviceProperties = new ServiceProperties("foo", "cluster-1", "/foo", Arrays.asList("degrader"), Collections.emptyMap(), null, null, prioritizedSchemes, null);
    UriProperties uriProperties = new UriProperties("cluster-1", uriData);
    // Create the delay generator for the uris
    URI expectedUri1 = URI.create("http://test.qa1.com:1234/foo");
    URI expectedUri2 = URI.create("http://test.qa2.com:2345/foo");
    URI expectedUri3 = URI.create("http://test.qa3.com:6789/foo");
    // Construct the delay patterns: for each URI there is a list of delays for each interval
    Map<String, List<Long>> delayMaps = new HashMap<>();
    delayMaps.put("http://test.qa1.com:1234/foo", Arrays.asList(50l, 60l, 75l, 55l, 60l, 80l, 50l));
    delayMaps.put("http://test.qa1.com:2345/foo", Arrays.asList(60l, 60l, 50l, 60l, 50l, 80l, 50l));
    delayMaps.put("http://test.qa1.com:6789/foo", Arrays.asList(80l, 3000l, 3000l, 3000l, 5000l, 80l, 50l));
    LoadBalancerSimulator.TimedValueGenerator<String> delayGenerator = new DelayValueGenerator(delayMaps, DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS);
    // Construct the QPS generator
    LoadBalancerSimulator.QPSGenerator qpsGenerator = new ConstantQPSGenerator(1000);
    // pass all the info to the simulator
    LoadBalancerSimulator loadBalancerSimulator = new LoadBalancerSimulator(serviceProperties, clusterProperties, uriProperties, delayGenerator, qpsGenerator);
    // Start the simulation
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS);
    printStates(loadBalancerSimulator);
    // the points for uri3 should be 100
    assertEquals(loadBalancerSimulator.getPoint("foo", DefaultPartitionAccessor.DEFAULT_PARTITION_ID, uri3), 100);
    // the uri3 should be used around 33% of all queries. Due to the hashring variance we need
    // to check the range.
    // uri3 will be degrading further after the previous interval
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) <= 0.375);
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) >= 0.295);
    // wait for 2 intervals due to call dropping involved
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri3 should be 80
    // Also if the loadbalancing strategy changed, the numbers could be lower
    assertEquals(loadBalancerSimulator.getPoint("foo", DefaultPartitionAccessor.DEFAULT_PARTITION_ID, uri3), 80);
    // the uri3 should be used around 28%, will be degrading further next
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) <= 0.32);
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) >= 0.24);
    // continue the simulation
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 2);
    printStates(loadBalancerSimulator);
    // the points for uri3 should be around 40
    assertEquals(loadBalancerSimulator.getPoint("foo", DefaultPartitionAccessor.DEFAULT_PARTITION_ID, uri3), 39);
    // the uri3 should be used around 16%, will be recovering next
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) <= 0.20);
    // assertTrue(loadBalancerSimulator.getCountPercent(expectedUri3) >= 0.12);
    loadBalancerSimulator.runWait(DegraderLoadBalancerStrategyConfig.DEFAULT_UPDATE_INTERVAL_MS * 3);
    printStates(loadBalancerSimulator);
    // the points for uri3 should be around 60, recovering
    assertEquals(loadBalancerSimulator.getPoint("foo", DefaultPartitionAccessor.DEFAULT_PARTITION_ID, uri3), 59);
    // Done. Shutdown the simulation
    loadBalancerSimulator.shutdown();
}
Also used : HashMap(java.util.HashMap) URI(java.net.URI) ServiceProperties(com.linkedin.d2.balancer.properties.ServiceProperties) PartitionData(com.linkedin.d2.balancer.properties.PartitionData) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) ClusterProperties(com.linkedin.d2.balancer.properties.ClusterProperties) List(java.util.List) HashMap(java.util.HashMap) Map(java.util.Map) Test(org.testng.annotations.Test)

Example 15 with UriProperties

use of com.linkedin.d2.balancer.properties.UriProperties in project rest.li by linkedin.

the class SimpleLoadBalancerStateTest method testSSLDisabledWithHttpsInstances.

@Test(groups = { "small", "back-end" })
public void testSSLDisabledWithHttpsInstances() throws URISyntaxException {
    reset();
    URI uri = URI.create("http://cluster-1/test");
    URI httpsUri = URI.create("https://cluster-1/test");
    List<String> schemes = new ArrayList<String>();
    Map<Integer, PartitionData> partitionData = new HashMap<Integer, PartitionData>(1);
    partitionData.put(DefaultPartitionAccessor.DEFAULT_PARTITION_ID, new PartitionData(1d));
    Map<URI, Map<Integer, PartitionData>> uriData = new HashMap<URI, Map<Integer, PartitionData>>();
    uriData.put(uri, partitionData);
    uriData.put(httpsUri, partitionData);
    schemes.add("https");
    schemes.add("http");
    assertNull(_state.getClient("service-1", uri));
    // set up state
    _state.listenToCluster("cluster-1", new NullStateListenerCallback());
    assertNull(_state.getClient("service-1", uri));
    _state.listenToService("service-1", new NullStateListenerCallback());
    assertNull(_state.getClient("service-1", uri));
    Map<String, Object> transportClientProperties = new HashMap<String, Object>();
    transportClientProperties.put(HttpClientFactory.HTTP_SSL_CONTEXT, _sslContext);
    transportClientProperties.put(HttpClientFactory.HTTP_SSL_PARAMS, _sslParameters);
    transportClientProperties = Collections.unmodifiableMap(transportClientProperties);
    ServiceProperties serviceProperties = new ServiceProperties("service-1", "cluster-1", "/test", Arrays.asList("random"), Collections.<String, Object>emptyMap(), transportClientProperties, null, schemes, null);
    _serviceRegistry.put("service-1", serviceProperties);
    assertNull(_state.getClient("service-1", uri));
    _uriRegistry.put("cluster-1", new UriProperties("cluster-1", uriData));
    List<LoadBalancerState.SchemeStrategyPair> schemeStrategyPairs = _state.getStrategiesForService("service-1", schemes);
    for (LoadBalancerState.SchemeStrategyPair pair : schemeStrategyPairs) {
        assertFalse("https".equalsIgnoreCase(pair.getScheme()), "https shouldn't be in any schemeStrategyPair");
    }
    TrackerClient client = _state.getClient("service-1", uri);
    assertNotNull(client);
    assertEquals(client.getUri(), uri);
    // Unfortunately, I don't know a good way to intercept the logs
    client = _state.getClient("service-1", httpsUri);
    assertNull(client, "shouldn't pick an https uri");
    _state.refreshTransportClientsPerService(serviceProperties);
}
Also used : HashMap(java.util.HashMap) ArrayList(java.util.ArrayList) URI(java.net.URI) LoadBalancerState(com.linkedin.d2.balancer.LoadBalancerState) NullStateListenerCallback(com.linkedin.d2.balancer.LoadBalancerState.NullStateListenerCallback) ServiceProperties(com.linkedin.d2.balancer.properties.ServiceProperties) TrackerClient(com.linkedin.d2.balancer.clients.TrackerClient) PartitionData(com.linkedin.d2.balancer.properties.PartitionData) UriProperties(com.linkedin.d2.balancer.properties.UriProperties) Map(java.util.Map) HashMap(java.util.HashMap) Test(org.testng.annotations.Test) DegraderLoadBalancerTest(com.linkedin.d2.balancer.strategies.degrader.DegraderLoadBalancerTest)

Aggregations

UriProperties (com.linkedin.d2.balancer.properties.UriProperties)50 HashMap (java.util.HashMap)39 ServiceProperties (com.linkedin.d2.balancer.properties.ServiceProperties)36 URI (java.net.URI)30 PartitionData (com.linkedin.d2.balancer.properties.PartitionData)29 ClusterProperties (com.linkedin.d2.balancer.properties.ClusterProperties)28 Test (org.testng.annotations.Test)27 Map (java.util.Map)22 ArrayList (java.util.ArrayList)19 None (com.linkedin.common.util.None)18 FutureCallback (com.linkedin.common.callback.FutureCallback)16 TrackerClient (com.linkedin.d2.balancer.clients.TrackerClient)16 UriPropertiesJsonSerializer (com.linkedin.d2.balancer.properties.UriPropertiesJsonSerializer)13 TransportClientFactory (com.linkedin.r2.transport.common.TransportClientFactory)13 HashSet (java.util.HashSet)13 ServicePropertiesJsonSerializer (com.linkedin.d2.balancer.properties.ServicePropertiesJsonSerializer)11 UriPropertiesMerger (com.linkedin.d2.balancer.properties.UriPropertiesMerger)11 DegraderLoadBalancerTest (com.linkedin.d2.balancer.strategies.degrader.DegraderLoadBalancerTest)11 NullStateListenerCallback (com.linkedin.d2.balancer.LoadBalancerState.NullStateListenerCallback)10 LoadBalancerStrategy (com.linkedin.d2.balancer.strategies.LoadBalancerStrategy)10