diff --git a/apps/inbandtelemetry/impl/src/main/java/org/onosproject/inbandtelemetry/impl/SimpleIntManager.java b/apps/inbandtelemetry/impl/src/main/java/org/onosproject/inbandtelemetry/impl/SimpleIntManager.java
index ffb6b4f..bf7dc18 100644
--- a/apps/inbandtelemetry/impl/src/main/java/org/onosproject/inbandtelemetry/impl/SimpleIntManager.java
+++ b/apps/inbandtelemetry/impl/src/main/java/org/onosproject/inbandtelemetry/impl/SimpleIntManager.java
@@ -72,6 +72,7 @@
 import java.util.Set;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -79,6 +80,8 @@
 import java.util.stream.Collectors;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
+import static org.onlab.util.Tools.groupedThreads;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
@@ -152,6 +155,8 @@
                 }
             };
 
+    protected ExecutorService eventExecutor;
+
     @Activate
     public void activate() {
 
@@ -206,6 +211,10 @@
         // Bootstrap config for already existing devices.
         triggerAllDeviceConfigure();
 
+        // Bootstrap core event executor before adding listener
+        eventExecutor = newSingleThreadScheduledExecutor(groupedThreads(
+                "onos/int", "events-%d", log));
+
         hostService.addListener(hostListener);
         deviceService.addListener(deviceListener);
 
@@ -256,6 +265,8 @@
         deviceService.getDevices().forEach(d -> cleanupDevice(d.id()));
         netcfgService.removeListener(appConfigListener);
         netcfgRegistry.unregisterConfigFactory(intAppConfigFactory);
+        eventExecutor.shutdownNow();
+        eventExecutor = null;
         log.info("Deactivated");
     }
 
@@ -503,30 +514,34 @@
     private class InternalHostListener implements HostListener {
         @Override
         public void event(HostEvent event) {
-            final DeviceId deviceId = event.subject().location().deviceId();
-            triggerDeviceConfigure(deviceId);
+            eventExecutor.execute(() -> {
+                final DeviceId deviceId = event.subject().location().deviceId();
+                triggerDeviceConfigure(deviceId);
+            });
         }
     }
 
     private class InternalDeviceListener implements DeviceListener {
         @Override
         public void event(DeviceEvent event) {
-            switch (event.type()) {
-                case DEVICE_ADDED:
-                case DEVICE_UPDATED:
-                case DEVICE_REMOVED:
-                case DEVICE_SUSPENDED:
-                case DEVICE_AVAILABILITY_CHANGED:
-                case PORT_ADDED:
-                case PORT_UPDATED:
-                case PORT_REMOVED:
-                    triggerDeviceConfigure(event.subject().id());
-                    return;
-                case PORT_STATS_UPDATED:
-                    return;
-                default:
-                    log.warn("Unknown device event type {}", event.type());
-            }
+            eventExecutor.execute(() -> {
+                switch (event.type()) {
+                    case DEVICE_ADDED:
+                    case DEVICE_UPDATED:
+                    case DEVICE_REMOVED:
+                    case DEVICE_SUSPENDED:
+                    case DEVICE_AVAILABILITY_CHANGED:
+                    case PORT_ADDED:
+                    case PORT_UPDATED:
+                    case PORT_REMOVED:
+                        triggerDeviceConfigure(event.subject().id());
+                        return;
+                    case PORT_STATS_UPDATED:
+                        return;
+                    default:
+                        log.warn("Unknown device event type {}", event.type());
+                }
+            });
         }
     }
 
@@ -580,56 +595,56 @@
 
         @Override
         public void event(NetworkConfigEvent event) {
-            switch (event.type()) {
-                case CONFIG_ADDED:
-                case CONFIG_UPDATED:
-                    event.config()
-                            .map(config -> (IntReportConfig) config)
-                            .ifPresent(config -> {
-                                IntDeviceConfig intDeviceConfig = IntDeviceConfig.builder()
-                                        .withMinFlowHopLatencyChangeNs(config.minFlowHopLatencyChangeNs())
-                                        .withCollectorPort(config.collectorPort())
-                                        .withCollectorIp(config.collectorIp())
-                                        .enabled(true)
-                                        .build();
-                                setConfig(intDeviceConfig);
+            eventExecutor.execute(() -> {
+                if (event.configClass() == IntReportConfig.class) {
+                    switch (event.type()) {
+                        case CONFIG_ADDED:
+                        case CONFIG_UPDATED:
+                            event.config()
+                                    .map(config -> (IntReportConfig) config)
+                                    .ifPresent(config -> {
+                                        IntDeviceConfig intDeviceConfig = IntDeviceConfig.builder()
+                                                .withMinFlowHopLatencyChangeNs(config.minFlowHopLatencyChangeNs())
+                                                .withCollectorPort(config.collectorPort())
+                                                .withCollectorIp(config.collectorIp())
+                                                .enabled(true)
+                                                .build();
+                                        setConfig(intDeviceConfig);
 
-                                // For each watched subnet, we install two INT rules.
-                                // One match on the source, another match on the destination.
-                                intentMap.clear();
-                                config.watchSubnets().forEach(subnet -> {
-                                    IntIntent.Builder intIntentBuilder = IntIntent.builder()
-                                            .withReportType(IntIntent.IntReportType.TRACKED_FLOW)
-                                            .withReportType(IntIntent.IntReportType.DROPPED_PACKET)
-                                            .withReportType(IntIntent.IntReportType.CONGESTED_QUEUE)
-                                            .withTelemetryMode(IntIntent.TelemetryMode.POSTCARD);
-                                    if (subnet.prefixLength() == 0) {
-                                        // Special case, match any packet
-                                        installIntIntent(intIntentBuilder
-                                                .withSelector(DefaultTrafficSelector.emptySelector())
-                                                .build());
-                                    } else {
-                                        TrafficSelector selector = DefaultTrafficSelector.builder()
-                                                .matchIPSrc(subnet)
-                                                .build();
-                                        installIntIntent(intIntentBuilder.withSelector(selector).build());
-                                        selector = DefaultTrafficSelector.builder()
-                                                .matchIPDst(subnet)
-                                                .build();
-                                        installIntIntent(intIntentBuilder.withSelector(selector).build());
-                                    }
-                                });
-                            });
-                    break;
-                // TODO: Support removing INT config.
-                default:
-                    break;
-            }
+                                        // For each watched subnet, we install two INT rules.
+                                        // One match on the source, another match on the destination.
+                                        intentMap.clear();
+                                        config.watchSubnets().forEach(subnet -> {
+                                            IntIntent.Builder intIntentBuilder = IntIntent.builder()
+                                                    .withReportType(IntIntent.IntReportType.TRACKED_FLOW)
+                                                    .withReportType(IntIntent.IntReportType.DROPPED_PACKET)
+                                                    .withReportType(IntIntent.IntReportType.CONGESTED_QUEUE)
+                                                    .withTelemetryMode(IntIntent.TelemetryMode.POSTCARD);
+                                            if (subnet.prefixLength() == 0) {
+                                                // Special case, match any packet
+                                                installIntIntent(intIntentBuilder
+                                                        .withSelector(DefaultTrafficSelector.emptySelector())
+                                                        .build());
+                                            } else {
+                                                TrafficSelector selector = DefaultTrafficSelector.builder()
+                                                        .matchIPSrc(subnet)
+                                                        .build();
+                                                installIntIntent(intIntentBuilder.withSelector(selector).build());
+                                                selector = DefaultTrafficSelector.builder()
+                                                        .matchIPDst(subnet)
+                                                        .build();
+                                                installIntIntent(intIntentBuilder.withSelector(selector).build());
+                                            }
+                                        });
+                                    });
+                            break;
+                        // TODO: Support removing INT config.
+                        default:
+                            break;
+                    }
+                }
+            });
         }
 
-        @Override
-        public boolean isRelevant(NetworkConfigEvent event) {
-            return event.configClass() == IntReportConfig.class;
-        }
     }
 }
diff --git a/apps/inbandtelemetry/impl/src/test/java/org/onosproject/inbandtelemetry/impl/SimpleIntManagerTest.java b/apps/inbandtelemetry/impl/src/test/java/org/onosproject/inbandtelemetry/impl/SimpleIntManagerTest.java
index 8519ed5..7fddf3c 100644
--- a/apps/inbandtelemetry/impl/src/test/java/org/onosproject/inbandtelemetry/impl/SimpleIntManagerTest.java
+++ b/apps/inbandtelemetry/impl/src/test/java/org/onosproject/inbandtelemetry/impl/SimpleIntManagerTest.java
@@ -22,6 +22,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
+import com.google.common.util.concurrent.MoreExecutors;
 import org.easymock.Capture;
 import org.easymock.EasyMock;
 import org.junit.After;
@@ -81,6 +82,7 @@
 import static org.easymock.EasyMock.verify;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.onlab.junit.TestTools.assertAfter;
 import static org.onosproject.net.behaviour.inbandtelemetry.IntProgrammable.IntFunctionality.POSTCARD;
 import static org.onosproject.net.behaviour.inbandtelemetry.IntProgrammable.IntFunctionality.SINK;
 import static org.onosproject.net.behaviour.inbandtelemetry.IntProgrammable.IntFunctionality.SOURCE;
@@ -151,6 +153,7 @@
         manager.hostService = hostService;
         manager.netcfgService = networkConfigService;
         manager.netcfgRegistry = networkConfigRegistry;
+        manager.eventExecutor = MoreExecutors.newDirectExecutorService();
 
         expect(coreService.registerApplication(APP_NAME))
                 .andReturn(APP_ID).anyTimes();
@@ -226,7 +229,7 @@
 
         // The INT intent installation order can be random, so we need to collect
         // all expected INT intents and check if actual intent exists.
-        assertEquals(5, intentMap.size());
+        assertAfter(50, 100, () -> assertEquals(5, intentMap.size()));
         intentMap.entrySet().forEach(entry -> {
             IntIntent actualIntIntent = entry.getValue().value();
             assertTrue(expectedIntIntents.contains(actualIntIntent));
diff --git a/apps/route-service/app/src/main/java/org/onosproject/routeservice/impl/RouteMonitor.java b/apps/route-service/app/src/main/java/org/onosproject/routeservice/impl/RouteMonitor.java
index ede60db..5ae2628 100644
--- a/apps/route-service/app/src/main/java/org/onosproject/routeservice/impl/RouteMonitor.java
+++ b/apps/route-service/app/src/main/java/org/onosproject/routeservice/impl/RouteMonitor.java
@@ -35,6 +35,7 @@
 
 import java.time.Duration;
 import java.util.Collection;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.stream.Collectors;
 
@@ -65,6 +66,9 @@
     private final ScheduledExecutorService reaperExecutor =
             newSingleThreadScheduledExecutor(groupedThreads("route/reaper", "", log));
 
+    private final ExecutorService eventExecutor = newSingleThreadScheduledExecutor(groupedThreads(
+            "onos/routemonitor", "events-%d", log));
+
     /**
      * Creates a new route monitor.
      *
@@ -94,6 +98,8 @@
     public void shutdown() {
         stopProcessing();
         clusterService.removeListener(clusterListener);
+        eventExecutor.shutdownNow();
+        reaperExecutor.shutdownNow();
         asyncLock.unlock();
     }
 
@@ -145,31 +151,33 @@
 
         @Override
         public void event(ClusterEvent event) {
-            switch (event.type()) {
-            case INSTANCE_DEACTIVATED:
-                NodeId id = event.subject().id();
-                log.info("Node {} deactivated", id);
+            eventExecutor.execute(() -> {
+                switch (event.type()) {
+                    case INSTANCE_DEACTIVATED:
+                        NodeId id = event.subject().id();
+                        log.info("Node {} deactivated", id);
 
-                // DistributedLock is introduced to guarantee that minority nodes won't try to remove
-                // routes that originated from majority nodes.
-                // Adding 15 seconds retry for the leadership election to be completed.
-                asyncLock.tryLock(Duration.ofSeconds(15)).whenComplete((result, error) -> {
-                    if (result != null && result.isPresent()) {
-                        log.debug("Lock obtained. Put {} into removal queue", id);
-                        queue.addOne(id);
-                        asyncLock.unlock();
-                    } else {
-                        log.debug("Fail to obtain lock. Do not remove routes from {}", id);
-                    }
-                });
-                break;
-            case INSTANCE_ADDED:
-            case INSTANCE_REMOVED:
-            case INSTANCE_ACTIVATED:
-            case INSTANCE_READY:
-            default:
-                break;
-            }
+                        // DistributedLock is introduced to guarantee that minority nodes won't try to remove
+                        // routes that originated from majority nodes.
+                        // Adding 15 seconds retry for the leadership election to be completed.
+                        asyncLock.tryLock(Duration.ofSeconds(15)).whenComplete((result, error) -> {
+                            if (result != null && result.isPresent()) {
+                                log.debug("Lock obtained. Put {} into removal queue", id);
+                                queue.addOne(id);
+                                asyncLock.unlock();
+                            } else {
+                                log.debug("Fail to obtain lock. Do not remove routes from {}", id);
+                            }
+                        });
+                        break;
+                    case INSTANCE_ADDED:
+                    case INSTANCE_REMOVED:
+                    case INSTANCE_ACTIVATED:
+                    case INSTANCE_READY:
+                    default:
+                        break;
+                }
+            });
         }
     }
 }
diff --git a/core/net/src/main/java/org/onosproject/net/group/impl/GroupDriverProvider.java b/core/net/src/main/java/org/onosproject/net/group/impl/GroupDriverProvider.java
index f86e4a1..1092d8d 100644
--- a/core/net/src/main/java/org/onosproject/net/group/impl/GroupDriverProvider.java
+++ b/core/net/src/main/java/org/onosproject/net/group/impl/GroupDriverProvider.java
@@ -117,12 +117,16 @@
     }
 
     private void pollGroups() {
-        deviceService.getAvailableDevices().forEach(device -> {
-            if (mastershipService.isLocalMaster(device.id()) &&
-                    device.is(GroupProgrammable.class)) {
-                pollDeviceGroups(device.id());
-            }
-        });
+        try {
+            deviceService.getAvailableDevices().forEach(device -> {
+                if (mastershipService.isLocalMaster(device.id()) &&
+                        device.is(GroupProgrammable.class)) {
+                    pollDeviceGroups(device.id());
+                }
+            });
+        } catch (Exception e) {
+            log.warn("Exception thrown while polling groups", e);
+        }
     }
 
     private void pollDeviceGroups(DeviceId deviceId) {
diff --git a/core/net/src/main/java/org/onosproject/net/meter/impl/MeterManager.java b/core/net/src/main/java/org/onosproject/net/meter/impl/MeterManager.java
index 39ef3d9..363876c 100644
--- a/core/net/src/main/java/org/onosproject/net/meter/impl/MeterManager.java
+++ b/core/net/src/main/java/org/onosproject/net/meter/impl/MeterManager.java
@@ -508,26 +508,29 @@
 
         @Override
         public void event(DeviceEvent event) {
-            switch (event.type()) {
-                case DEVICE_REMOVED:
-                case DEVICE_AVAILABILITY_CHANGED:
-                    DeviceId deviceId = event.subject().id();
-                    if (!deviceService.isAvailable(deviceId)) {
-                        BasicDeviceConfig cfg = netCfgService.getConfig(deviceId, BasicDeviceConfig.class);
-                        //if purgeOnDisconnection is set for the device or it's a global configuration
-                        // lets remove the meters.
-                        boolean purge = cfg != null && cfg.isPurgeOnDisconnectionConfigured() ?
-                                cfg.purgeOnDisconnection() : purgeOnDisconnection;
-                        if (purge) {
-                            log.info("PurgeOnDisconnection is requested for device {}, " +
-                                             "removing meters", deviceId);
-                            store.purgeMeter(deviceId);
+            DeviceId deviceId = event.subject().id();
+            meterInstallers.execute(() -> {
+                switch (event.type()) {
+                    case DEVICE_REMOVED:
+                    case DEVICE_AVAILABILITY_CHANGED:
+                        if (!deviceService.isAvailable(deviceId)) {
+                            BasicDeviceConfig cfg = netCfgService.getConfig(deviceId, BasicDeviceConfig.class);
+                            //if purgeOnDisconnection is set for the device or it's a global configuration
+                            // lets remove the meters.
+                            boolean purge = cfg != null && cfg.isPurgeOnDisconnectionConfigured() ?
+                                    cfg.purgeOnDisconnection() : purgeOnDisconnection;
+                            if (purge) {
+                                log.info("PurgeOnDisconnection is requested for device {}, " +
+                                        "removing meters", deviceId);
+                                store.purgeMeter(deviceId);
+                            }
                         }
-                    }
-                    break;
-                default:
-                    break;
-            }
+                        break;
+                    default:
+                        break;
+                }
+            }, deviceId.hashCode());
+
         }
     }
 
diff --git a/providers/general/device/src/main/java/org/onosproject/provider/general/device/impl/GnmiDeviceStateSubscriber.java b/providers/general/device/src/main/java/org/onosproject/provider/general/device/impl/GnmiDeviceStateSubscriber.java
index d55ca7f..f36e7a8 100644
--- a/providers/general/device/src/main/java/org/onosproject/provider/general/device/impl/GnmiDeviceStateSubscriber.java
+++ b/providers/general/device/src/main/java/org/onosproject/provider/general/device/impl/GnmiDeviceStateSubscriber.java
@@ -52,9 +52,13 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.locks.Lock;
 import java.util.stream.Collectors;
 
+import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+
 /**
  * Entity that manages gNMI subscription for devices using OpenConfig models and
  * that reports relevant events to the core.
@@ -78,6 +82,8 @@
 
     private final Striped<Lock> deviceLocks = Striped.lock(30);
 
+    private ExecutorService eventExecutor;
+
     GnmiDeviceStateSubscriber(GnmiController gnmiController, DeviceService deviceService,
                               MastershipService mastershipService,
                               DeviceProviderService providerService) {
@@ -88,6 +94,8 @@
     }
 
     public void activate() {
+        eventExecutor = newSingleThreadScheduledExecutor(groupedThreads(
+                "onos/gnmi", "events-%d", log));
         deviceService.addListener(deviceEventListener);
         mastershipService.addListener(mastershipListener);
         gnmiController.addListener(gnmiEventListener);
@@ -100,6 +108,8 @@
         deviceService.removeListener(deviceEventListener);
         mastershipService.removeListener(mastershipListener);
         gnmiController.removeListener(gnmiEventListener);
+        eventExecutor.shutdownNow();
+        eventExecutor = null;
     }
 
     private void checkSubscription(DeviceId deviceId) {
@@ -248,19 +258,21 @@
 
         @Override
         public void event(GnmiEvent event) {
-            if (!deviceSubscribed.containsKey(event.subject().deviceId())) {
-                log.warn("Received gNMI event from {}, but we did'nt expect to " +
-                                 "be subscribed to it! Discarding event...",
-                         event.subject().deviceId());
-                return;
-            }
+            eventExecutor.execute(() -> {
+                if (!deviceSubscribed.containsKey(event.subject().deviceId())) {
+                    log.warn("Received gNMI event from {}, but we did'nt expect to " +
+                                    "be subscribed to it! Discarding event...",
+                            event.subject().deviceId());
+                    return;
+                }
 
-            log.debug("Received gNMI event {}", event.toString());
-            if (event.type() == GnmiEvent.Type.UPDATE) {
-                handleGnmiUpdate((GnmiUpdate) event.subject());
-            } else {
-                log.debug("Unsupported gNMI event type: {}", event.type());
-            }
+                log.debug("Received gNMI event {}", event.toString());
+                if (event.type() == GnmiEvent.Type.UPDATE) {
+                    handleGnmiUpdate((GnmiUpdate) event.subject());
+                } else {
+                    log.debug("Unsupported gNMI event type: {}", event.type());
+                }
+            });
         }
     }
 
@@ -268,7 +280,7 @@
 
         @Override
         public void event(MastershipEvent event) {
-            checkSubscription(event.subject());
+            eventExecutor.execute(() -> checkSubscription(event.subject()));
         }
     }
 
@@ -276,18 +288,20 @@
 
         @Override
         public void event(DeviceEvent event) {
-            switch (event.type()) {
-                case DEVICE_ADDED:
-                case DEVICE_AVAILABILITY_CHANGED:
-                case DEVICE_UPDATED:
-                case DEVICE_REMOVED:
-                case PORT_ADDED:
-                case PORT_REMOVED:
-                    checkSubscription(event.subject().id());
-                    break;
-                default:
-                    break;
-            }
+            eventExecutor.execute(() -> {
+                switch (event.type()) {
+                    case DEVICE_ADDED:
+                    case DEVICE_AVAILABILITY_CHANGED:
+                    case DEVICE_UPDATED:
+                    case DEVICE_REMOVED:
+                    case PORT_ADDED:
+                    case PORT_REMOVED:
+                        checkSubscription(event.subject().id());
+                        break;
+                    default:
+                        break;
+                }
+            });
         }
     }
 }