Dynamic Configuration and Dynamic Configuration Service (#2810)

* Implement the base of config API module.

* Finish configuration module codebases w/o tests, revert some changes.

* Finish mock tests.

* Add new gRPC service for configuration.

* Make gRPC configuration sync provider works.

* Add database slow statement dynamic setting.

* Finish the dynamic configuration service.

* Fix version.

docs/en/guides/How-to-build.md

@@ -72,6 +72,7 @@ a oap image with name `bar/oap:foo`, run the following command
     * `grpc-java` and `java` folders in **oap-server/server-core/target/generated-sources/protobuf**
     * `grpc-java` and `java` folders in **oap-server/server-receiver-plugin/receiver-proto/target/generated-sources/protobuf**
     * `grpc-java` and `java` folders in **oap-server/exporter/target/generated-sources/protobuf**
+    * `grpc-java` and `java` folders in **oap-server/server-configuration/grpc-configuration-sync/target/generated-sources/protobuf**
     * `antlr4` folder in **oap-server/generate-tool-grammar/target/generated-sources**
     * `oal` folder in **oap-server/generated-analysis/target/generated-sources**
     

docs/en/setup/backend/backend-setup.md

@@ -81,6 +81,8 @@ scale and support high payload, you may need this.
 system.
 1. [Time To Live (TTL)](ttl.md). Metrics and trace are time series data, they would be saved forever, you could 
 set the expired time for each dimension.
+1. [Dynamic Configuration](dynamic-config.md). Make configuration of OAP changed dynamic, from remote service
+or 3rd party configuration management system.
 
 ## Telemetry for backend
 OAP backend cluster itself underlying is a distributed streaming process system. For helping the Ops team,

docs/en/setup/backend/dynamic-config.md

+# Dynamic Configuration
+SkyWalking Configurations mostly are set through `application.yml` and OS system environment variables.
+But some of them are supporting dynamic settings from upstream management system.
+
+Right now, SkyWalking supports following dynamic configurations.
+
+| Config Key | Value Description | Value Format Example |
+|:----:|:----:|:----:|
+|receiver-trace.default.slowDBAccessThreshold| Thresholds of slow Database statement, override `receiver-trace/default/slowDBAccessThreshold` of `applciation.yml`. | default:200,mongodb:50|
+
+
+This feature depends on upstream service, so it is **OFF** as default.
+```yaml
+configuration:
+  none:
+```
+
+## Dynamic Configuration Service, DCS
+[Dynamic Configuration Service](../../../../oap-server/server-configuration/grpc-configuration-sync/src/main/proto/configuration-service.proto) 
+is a gRPC service, which requires the upstream system implemented.
+The SkyWalking OAP fetches the configuration from the implementation(any system), after you open this implementation like this.
+
+```yaml
+configuration:
+  grpc:
+    # Upstream system hostname
+    host: 127.0.0.1
+    # Upstream system port
+    port: 9555
+    #period : 60 # Unit seconds, sync period. Default fetch every 60 seconds.
+    #clusterName: "default" # the name of current cluster, set the name if you want to upstream system known.  
+```
+
+
+## 3rd party Configuration Center
+We are welcome contributions to implement this module provider to support popular configuration center, 
+such as Zookeeper, etcd, Consul, Nacos. Submit issue to discuss.
+
+

oap-server/pom.xml

@@ -42,6 +42,7 @@
         <module>server-telemetry</module>
         <module>generate-tool-grammar</module>
         <module>exporter</module>
+        <module>server-configuration</module>
     </modules>
 
     <properties>

oap-server/server-configuration/configuration-api/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to You under the Apache License, Version 2.0
+  ~ (the "License"); you may not use this file except in compliance with
+  ~ the License.  You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  ~
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>server-configuration</artifactId>
+        <groupId>org.apache.skywalking</groupId>
+        <version>6.2.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>configuration-api</artifactId>
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>library-module</artifactId>
+            <version>${project.version}</version>
+            <scope>compile</scope>
+        </dependency>
+    </dependencies>
+
+
+</project>
\ No newline at end of file

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/AbstractConfigurationProvider.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import org.apache.skywalking.oap.server.library.module.*;
+
+/**
+ * The recommendation default base implementor of Configuration module. The real implementor could extend this provider
+ * to make a new one, easily.
+ *
+ * @author wusheng
+ */
+public abstract class AbstractConfigurationProvider extends ModuleProvider {
+    private ConfigWatcherRegister configWatcherRegister;
+
+    @Override public Class<? extends ModuleDefine> module() {
+        return ConfigurationModule.class;
+    }
+
+    @Override public void prepare() throws ServiceNotProvidedException, ModuleStartException {
+        configWatcherRegister = initConfigReader();
+        this.registerServiceImplementation(DynamicConfigurationService.class, configWatcherRegister);
+    }
+
+    protected abstract ConfigWatcherRegister initConfigReader() throws ModuleStartException;
+
+    @Override public void start() throws ServiceNotProvidedException, ModuleStartException {
+
+    }
+
+    @Override public void notifyAfterCompleted() throws ServiceNotProvidedException, ModuleStartException {
+        configWatcherRegister.start();
+    }
+
+    @Override public String[] requiredModules() {
+        return new String[0];
+    }
+
+}

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/ConfigChangeWatcher.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import lombok.*;
+import org.apache.skywalking.oap.server.library.module.*;
+
+/**
+ * ConfigChangeWatcher represents a watcher implementor, it will be called when the target value changed.
+ *
+ * @author wusheng
+ */
+@Getter
+public abstract class ConfigChangeWatcher {
+    private final String module;
+    private final ModuleProvider provider;
+    private final String itemName;
+
+    public ConfigChangeWatcher(String module, ModuleProvider provider, String itemName) {
+        this.module = module;
+        this.provider = provider;
+        this.itemName = itemName;
+    }
+
+    /**
+     * Notify the watcher, the new value received.
+     *
+     * @param value of new.
+     */
+    public abstract void notify(ConfigChangeEvent value);
+
+    /**
+     * @return current value of current config.
+     */
+    public abstract String value();
+
+    @Override public String toString() {
+        return "ConfigChangeWatcher{" +
+            "module=" + module +
+            ", provider=" + provider +
+            ", itemName='" + itemName + '\'' +
+            '}';
+    }
+
+    @Setter(AccessLevel.PACKAGE)
+    @Getter
+    public static class ConfigChangeEvent {
+        private String newValue;
+        private EventType eventType;
+
+        public ConfigChangeEvent(String newValue,
+            EventType eventType) {
+            this.newValue = newValue;
+            this.eventType = eventType;
+        }
+    }
+
+    public enum EventType {
+        ADD, MODIFY, DELETE
+    }
+}

oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/receiver/trace/provider/DBLatencyThresholds.java → oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/ConfigTable.java

@@ -16,36 +16,33 @@
  *
  */
 
-package org.apache.skywalking.oap.server.receiver.trace.provider;
+package org.apache.skywalking.oap.server.configuration.api;
 
 import java.util.*;
+import lombok.*;
 
 /**
+ * ConfigTable contains all config.
+ *
  * @author wusheng
  */
-public class DBLatencyThresholds {
-    private Map<String, Integer> thresholds;
+public class ConfigTable {
+    @Getter
+    private List<ConfigItem> items = new ArrayList<>();
 
-    DBLatencyThresholds(String config) {
-        thresholds = new HashMap<>();
-        String[] settings = config.split(",");
-        for (String setting : settings) {
-            String[] typeValue = setting.split(":");
-            if (typeValue.length == 2) {
-                thresholds.put(typeValue[0].trim().toLowerCase(), Integer.parseInt(typeValue[1].trim()));
-            }
-        }
-        if (!thresholds.containsKey("default")) {
-            thresholds.put("default", 10000);
-        }
+    public void add(ConfigItem item) {
+        items.add(item);
     }
 
-    public int getThreshold(String type) {
-        type = type.toLowerCase();
-        if (thresholds.containsKey(type)) {
-            return thresholds.get(type);
-        } else {
-            return thresholds.get("default");
+    @Getter
+    @Setter
+    public static class ConfigItem {
+        private String name;
+        private String value;
+
+        public ConfigItem(String name, String value) {
+            this.name = name;
+            this.value = value;
         }
     }
 }

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/ConfigWatcherRegister.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import java.util.*;
+import java.util.concurrent.*;
+import lombok.Getter;
+import org.apache.skywalking.apm.util.RunnableWithExceptionProtection;
+import org.slf4j.*;
+
+/**
+ * The default implementor of Config Watcher register.
+ *
+ * @author wusheng
+ */
+public abstract class ConfigWatcherRegister implements DynamicConfigurationService {
+    private static final Logger logger = LoggerFactory.getLogger(ConfigWatcherRegister.class);
+    public static final String LINE_SEPARATOR = System.getProperty("line.separator", "\n");
+
+    private Register register = new Register();
+    private volatile boolean isStarted = false;
+    private final long syncPeriod;
+
+    public ConfigWatcherRegister() {
+        this(60);
+    }
+
+    public ConfigWatcherRegister(long syncPeriod) {
+        this.syncPeriod = syncPeriod;
+    }
+
+    @Override synchronized public void registerConfigChangeWatcher(ConfigChangeWatcher watcher) {
+        if (isStarted) {
+            throw new IllegalStateException("Config Register has been started. Can't register new watcher.");
+        }
+
+        WatcherHolder holder = new WatcherHolder(watcher);
+        if (register.containsKey(holder.getKey())) {
+            throw new IllegalStateException("Duplicate register, watcher=" + watcher);
+        }
+        register.put(holder.getKey(), holder);
+    }
+
+    public void start() {
+        isStarted = true;
+
+        configSync();
+        logger.info("Current configurations after the bootstrap sync." + LINE_SEPARATOR + register.toString());
+
+        Executors.newSingleThreadScheduledExecutor().scheduleAtFixedRate(
+            new RunnableWithExceptionProtection(() -> configSync(),
+                t -> logger.error("Sync config center error.", t)), syncPeriod, syncPeriod, TimeUnit.SECONDS);
+    }
+
+    void configSync() {
+        ConfigTable configTable = readConfig();
+
+        configTable.getItems().forEach(item -> {
+            String itemName = item.getName();
+            WatcherHolder holder = register.get(itemName);
+            if (holder != null) {
+                ConfigChangeWatcher watcher = holder.getWatcher();
+                String newItemValue = item.getValue();
+                if (newItemValue == null) {
+                    if (watcher.value() != null) {
+                        // Notify watcher, the new value is null with delete event type.
+                        watcher.notify(new ConfigChangeWatcher.ConfigChangeEvent(null, ConfigChangeWatcher.EventType.DELETE));
+                    } else {
+                        // Don't need to notify, stay in null.
+                    }
+                } else {
+                    if (!newItemValue.equals(watcher.value())) {
+                        watcher.notify(new ConfigChangeWatcher.ConfigChangeEvent(newItemValue, ConfigChangeWatcher.EventType.MODIFY));
+                    } else {
+                        // Don't need to notify, stay in the same config value.
+                    }
+                }
+            } else {
+                logger.warn("Config {} from configuration center, doesn't match any watcher, ignore.", itemName);
+            }
+        });
+
+        logger.trace("Current configurations after the sync." + LINE_SEPARATOR + register.toString());
+    }
+
+    public abstract ConfigTable readConfig();
+
+    public class Register {
+        private Map<String, WatcherHolder> register = new HashMap<>();
+
+        private boolean containsKey(String key) {
+            return register.containsKey(key);
+        }
+
+        private void put(String key, WatcherHolder holder) {
+            register.put(key, holder);
+        }
+
+        public WatcherHolder get(String name) {
+            return register.get(name);
+        }
+
+        @Override public String toString() {
+            StringBuilder registerTableDescription = new StringBuilder();
+            registerTableDescription.append("Following dynamic config items are available.").append(LINE_SEPARATOR);
+            registerTableDescription.append("---------------------------------------------").append(LINE_SEPARATOR);
+            register.forEach((key, holder) -> {
+                ConfigChangeWatcher watcher = holder.getWatcher();
+                registerTableDescription.append("key:").append(key)
+                    .append("    module:").append(watcher.getModule())
+                    .append("    provider:").append(watcher.getProvider().name())
+                    .append("    value(current):").append(watcher.value())
+                    .append(LINE_SEPARATOR);
+            });
+            return registerTableDescription.toString();
+        }
+    }
+
+    @Getter
+    private class WatcherHolder {
+        private ConfigChangeWatcher watcher;
+        private final String key;
+
+        public WatcherHolder(ConfigChangeWatcher watcher) {
+            this.watcher = watcher;
+            this.key = String.join(".", watcher.getModule(), watcher.getProvider().name(), watcher.getItemName());
+        }
+    }
+}

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/ConfigurationModule.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import org.apache.skywalking.oap.server.library.module.ModuleDefine;
+
+/**
+ * Configuration Module sync the settings from remote service, the remote service could be implemented by this module
+ * provider.
+ *
+ * Any configuration item in the whole OAP backend could register a watcher to configuration module, the item change
+ * watcher will be called, if the value changed.
+ *
+ * @author wusheng
+ */
+public class ConfigurationModule extends ModuleDefine {
+    public static final String NAME = "configuration";
+
+    public ConfigurationModule() {
+        super(NAME);
+    }
+
+    @Override public Class[] services() {
+        return new Class[] {DynamicConfigurationService.class};
+    }
+}

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/DynamicConfigurationService.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import org.apache.skywalking.oap.server.library.module.*;
+
+/**
+ * DynamicConfigurationService provides API to register config change watcher.
+ *
+ * @author wusheng
+ */
+public interface DynamicConfigurationService extends Service {
+    /**
+     * Register a watcher to the target value
+     *
+     * @param watcher to register
+     */
+    void registerConfigChangeWatcher(ConfigChangeWatcher watcher);
+}

oap-server/server-configuration/configuration-api/src/main/java/org/apache/skywalking/oap/server/configuration/api/NoneConfigurationProvider.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import org.apache.skywalking.oap.server.library.module.*;
+
+/**
+ * A nutshell configuration implementor.
+ *
+ * @author wusheng
+ */
+public class NoneConfigurationProvider extends ModuleProvider {
+    @Override public String name() {
+        return "none";
+    }
+
+    @Override public Class<? extends ModuleDefine> module() {
+        return ConfigurationModule.class;
+    }
+
+    @Override public ModuleConfig createConfigBeanIfAbsent() {
+        return null;
+    }
+
+    @Override public void prepare() throws ServiceNotProvidedException, ModuleStartException {
+        this.registerServiceImplementation(DynamicConfigurationService.class, new DynamicConfigurationService() {
+            @Override public void registerConfigChangeWatcher(ConfigChangeWatcher watcher) {
+
+            }
+        });
+    }
+
+    @Override public void start() throws ServiceNotProvidedException, ModuleStartException {
+
+    }
+
+    @Override public void notifyAfterCompleted() throws ServiceNotProvidedException, ModuleStartException {
+
+    }
+
+    @Override public String[] requiredModules() {
+        return new String[0];
+    }
+}

oap-server/server-configuration/configuration-api/src/main/resources/META-INF/services/org.apache.skywalking.oap.server.library.module.ModuleDefine

+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+#
+
+org.apache.skywalking.oap.server.configuration.api.ConfigurationModule
\ No newline at end of file

oap-server/server-configuration/configuration-api/src/main/resources/META-INF/services/org.apache.skywalking.oap.server.library.module.ModuleProvider

+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+#
+#
+
+org.apache.skywalking.oap.server.configuration.api.NoneConfigurationProvider
\ No newline at end of file

oap-server/server-configuration/configuration-api/src/test/java/org/apache/skywalking/oap/server/configuration/api/ConfigWatcherRegisterTest.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.api;
+
+import org.apache.skywalking.oap.server.library.module.*;
+import org.junit.*;
+import org.powermock.reflect.Whitebox;
+
+/**
+ * @author wusheng
+ */
+public class ConfigWatcherRegisterTest {
+    private ConfigWatcherRegister register;
+
+    @Before
+    public void setup() {
+        register = new MockConfigWatcherRegister();
+    }
+
+    @After
+    public void tearDown() {
+        register = null;
+    }
+
+    @Test
+    public void testInit() {
+        final String[] newValue = new String[1];
+
+        register.registerConfigChangeWatcher(new ConfigChangeWatcher("MockModule", new MockProvider(), "prop2") {
+            @Override public void notify(ConfigChangeEvent value) {
+                newValue[0] = value.getNewValue();
+            }
+
+            @Override public String value() {
+                return null;
+            }
+        });
+
+        register.configSync();
+
+        Assert.assertEquals("abc2", newValue[0]);
+    }
+
+    @Test
+    public void testRegisterTableLog() {
+        register.registerConfigChangeWatcher(new ConfigChangeWatcher("MockModule", new MockProvider(), "prop2") {
+            @Override public void notify(ConfigChangeEvent value) {
+            }
+
+            @Override public String value() {
+                return null;
+            }
+        });
+
+        register.configSync();
+        ConfigWatcherRegister.Register registerTable = Whitebox.getInternalState(this.register, "register");
+
+        String expected = "Following dynamic config items are available." + ConfigWatcherRegister.LINE_SEPARATOR +
+            "---------------------------------------------" + ConfigWatcherRegister.LINE_SEPARATOR +
+            "key:MockModule.provider.prop2    module:MockModule    provider:provider    value(current):null" + ConfigWatcherRegister.LINE_SEPARATOR;
+
+        Assert.assertEquals(expected, registerTable.toString());
+    }
+
+    public static class MockConfigWatcherRegister extends ConfigWatcherRegister {
+
+        @Override public ConfigTable readConfig() {
+            ConfigTable.ConfigItem item1 = new ConfigTable.ConfigItem("module.provider.prop1", "abc");
+            ConfigTable.ConfigItem item2 = new ConfigTable.ConfigItem("MockModule.provider.prop2", "abc2");
+
+            ConfigTable table = new ConfigTable();
+            table.add(item1);
+            table.add(item2);
+            return table;
+        }
+    }
+
+    public static class MockModule extends ModuleDefine {
+
+        public MockModule() {
+            super("MockModule");
+        }
+
+        @Override public Class[] services() {
+            return new Class[0];
+        }
+    }
+
+    public static class MockProvider extends ModuleProvider {
+
+        @Override public String name() {
+            return "provider";
+        }
+
+        @Override public Class<? extends ModuleDefine> module() {
+            return MockModule.class;
+        }
+
+        @Override public ModuleConfig createConfigBeanIfAbsent() {
+            return null;
+        }
+
+        @Override public void prepare() throws ServiceNotProvidedException, ModuleStartException {
+
+        }
+
+        @Override public void start() throws ServiceNotProvidedException, ModuleStartException {
+
+        }
+
+        @Override public void notifyAfterCompleted() throws ServiceNotProvidedException, ModuleStartException {
+
+        }
+
+        @Override public String[] requiredModules() {
+            return new String[0];
+        }
+    }
+}

oap-server/server-configuration/grpc-configuration-sync/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to You under the Apache License, Version 2.0
+  ~ (the "License"); you may not use this file except in compliance with
+  ~ the License.  You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  ~
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>server-configuration</artifactId>
+        <groupId>org.apache.skywalking</groupId>
+        <version>6.2.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>grpc-configuration-sync</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>configuration-api</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>library-client</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-netty</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-protobuf</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.grpc</groupId>
+            <artifactId>grpc-stub</artifactId>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <extensions>
+            <extension>
+                <groupId>kr.motd.maven</groupId>
+                <artifactId>os-maven-plugin</artifactId>
+                <version>1.4.1.Final</version>
+            </extension>
+        </extensions>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-resources-plugin</artifactId>
+                <version>2.4.3</version>
+                <configuration>
+                    <encoding>${project.build.sourceEncoding}</encoding>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.xolstice.maven.plugins</groupId>
+                <artifactId>protobuf-maven-plugin</artifactId>
+                <version>0.5.0</version>
+                <configuration>
+                    <!--
+                      The version of protoc must match protobuf-java. If you don't depend on
+                      protobuf-java directly, you will be transitively depending on the
+                      protobuf-java version that grpc depends on.
+                    -->
+                    <protocArtifact>com.google.protobuf:protoc:3.3.0:exe:${os.detected.classifier}
+                    </protocArtifact>
+                    <pluginId>grpc-java</pluginId>
+                    <pluginArtifact>io.grpc:protoc-gen-grpc-java:1.4.0:exe:${os.detected.classifier}
+                    </pluginArtifact>
+                </configuration>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>compile</goal>
+                            <goal>compile-custom</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+</project>
\ No newline at end of file

oap-server/server-configuration/grpc-configuration-sync/src/main/java/org/apache/skywalking/oap/server/configuration/grpc/GRPCConfigWatcherRegister.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.grpc;
+
+import io.grpc.netty.NettyChannelBuilder;
+import org.apache.skywalking.oap.server.configuration.api.*;
+import org.apache.skywalking.oap.server.configuration.service.*;
+import org.slf4j.*;
+
+/**
+ * @author wusheng
+ */
+public class GRPCConfigWatcherRegister extends ConfigWatcherRegister {
+    private static final Logger logger = LoggerFactory.getLogger(GRPCConfigWatcherRegister.class);
+
+    private RemoteEndpointSettings settings;
+    private ConfigurationServiceGrpc.ConfigurationServiceBlockingStub stub;
+
+    public GRPCConfigWatcherRegister(RemoteEndpointSettings settings) {
+        super(settings.getPeriod());
+        this.settings = settings;
+        stub = ConfigurationServiceGrpc.newBlockingStub(NettyChannelBuilder.forAddress(settings.getHost(), settings.getPort()).usePlaintext().build());
+    }
+
+    @Override public ConfigTable readConfig() {
+        ConfigTable table = new ConfigTable();
+        try {
+            ConfigurationResponse response = stub.call(ConfigurationRequest.newBuilder().setClusterName(settings.getClusterName()).build());
+            response.getConfigTableList().forEach(config -> {
+                table.add(new ConfigTable.ConfigItem(config.getName(), config.getValue()));
+            });
+        } catch (Exception e) {
+            logger.error("Remote config center [" + settings + "] is not available.", e);
+        }
+        return table;
+    }
+}

oap-server/server-configuration/grpc-configuration-sync/src/main/java/org/apache/skywalking/oap/server/configuration/grpc/GRPCConfigurationProvider.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.grpc;
+
+import com.google.common.base.Strings;
+import org.apache.skywalking.oap.server.configuration.api.*;
+import org.apache.skywalking.oap.server.library.module.*;
+
+/**
+ * Get configuration from remote through gRPC protocol.
+ *
+ * Read configuration-service.proto for more details.
+ *
+ * @author wusheng
+ */
+public class GRPCConfigurationProvider extends AbstractConfigurationProvider {
+    private RemoteEndpointSettings settings;
+
+    public GRPCConfigurationProvider() {
+        settings = new RemoteEndpointSettings();
+    }
+
+    @Override public String name() {
+        return "grpc";
+    }
+
+    @Override public ModuleConfig createConfigBeanIfAbsent() {
+        return settings;
+    }
+
+    @Override protected ConfigWatcherRegister initConfigReader() throws ModuleStartException {
+        if (Strings.isNullOrEmpty(settings.getHost())) {
+            throw new ModuleStartException("No host setting.");
+        }
+        if (settings.getPort() < 1) {
+            throw new ModuleStartException("No port setting.");
+        }
+
+        return new GRPCConfigWatcherRegister(settings);
+    }
+}

oap-server/server-configuration/grpc-configuration-sync/src/main/java/org/apache/skywalking/oap/server/configuration/grpc/RemoteEndpointSettings.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.configuration.grpc;
+
+import lombok.*;
+import org.apache.skywalking.oap.server.library.module.ModuleConfig;
+
+/**
+ * @author wusheng
+ */
+@Setter
+@Getter
+public class RemoteEndpointSettings extends ModuleConfig {
+    private String host;
+    private int port;
+    private String clusterName = "default";
+    // Sync configuration per 60 seconds.
+    private int period = 60;
+
+    @Override public String toString() {
+        return "RemoteEndpointSettings{" +
+            "host='" + host + '\'' +
+            ", port=" + port +
+            ", clusterName='" + clusterName + '\'' +
+            '}';
+    }
+}

oap-server/server-configuration/grpc-configuration-sync/src/main/proto/configuration-service.proto

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "org.apache.skywalking.oap.server.configuration.service";
+
+service ConfigurationService {
+    rpc call (ConfigurationRequest) returns (ConfigurationResponse) {
+    }
+}
+
+message ConfigurationRequest {
+    // Logic name of this cluster,
+    // in case the remote configuration center implementation support
+    // configuration management for multiple clusters.
+    string clusterName = 1;
+}
+
+message ConfigurationResponse {
+    // Include all config items.
+    // All config name should be not empty,
+    // the name is composed by "module name"."provider name"."item name".
+    // Each watcher implementor provides this, and it will be notified when the value changed.
+    //
+    // If the config center wants to set the value to NULL or empty,
+    // must set the name with empty value explicitly.
+    repeated Config configTable = 1;
+}
+
+message Config {
+    string name = 1;
+    string value = 2;
+}
\ No newline at end of file

oap-server/server-configuration/grpc-configuration-sync/src/main/resources/META-INF/services/org.apache.skywalking.oap.server.library.module.ModuleProvider

+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+#
+
+org.apache.skywalking.oap.server.configuration.grpc.GRPCConfigurationProvider
\ No newline at end of file

oap-server/server-configuration/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to You under the Apache License, Version 2.0
+  ~ (the "License"); you may not use this file except in compliance with
+  ~ the License.  You may obtain a copy of the License at
+  ~
+  ~     http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  ~
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>oap-server</artifactId>
+        <groupId>org.apache.skywalking</groupId>
+        <version>6.2.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>server-configuration</artifactId>
+    <packaging>pom</packaging>
+    <modules>
+        <module>configuration-api</module>
+        <module>grpc-configuration-sync</module>
+    </modules>
+
+</project>
\ No newline at end of file

oap-server/server-core/pom.xml

@@ -44,6 +44,11 @@
             <artifactId>telemetry-api</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>configuration-api</artifactId>
+            <version>${project.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.apache.skywalking</groupId>
             <artifactId>library-util</artifactId>

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/CoreModuleProvider.java

@@ -19,6 +19,7 @@
 package org.apache.skywalking.oap.server.core;
 
 import java.io.IOException;
+import org.apache.skywalking.oap.server.configuration.api.ConfigurationModule;
 import org.apache.skywalking.oap.server.core.analysis.*;
 import org.apache.skywalking.oap.server.core.annotation.AnnotationScan;
 import org.apache.skywalking.oap.server.core.cache.*;
@@ -188,6 +189,6 @@ public class CoreModuleProvider extends ModuleProvider {
 
     @Override
     public String[] requiredModules() {
-        return new String[] {TelemetryModule.NAME};
+        return new String[] {TelemetryModule.NAME, ConfigurationModule.NAME};
     }
 }

oap-server/server-library/library-module/src/main/java/org/apache/skywalking/oap/server/library/module/ModuleStartException.java

@@ -22,6 +22,9 @@ package org.apache.skywalking.oap.server.library.module;
  * @author peng-yongsheng
  */
 public class ModuleStartException extends Exception {
+    public ModuleStartException(String message) {
+        super(message);
+    }
 
     public ModuleStartException(String message, Throwable cause) {
         super(message, cause);

oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/receiver/trace/provider/DBLatencyThresholdsAndWatcher.java

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package org.apache.skywalking.oap.server.receiver.trace.provider;
+
+import java.util.*;
+import java.util.concurrent.atomic.AtomicReference;
+import org.apache.skywalking.oap.server.configuration.api.ConfigChangeWatcher;
+import org.apache.skywalking.oap.server.receiver.trace.module.TraceModule;
+
+/**
+ * @author wusheng
+ */
+public class DBLatencyThresholdsAndWatcher extends ConfigChangeWatcher {
+    private AtomicReference<Map<String, Integer>> thresholds;
+    private AtomicReference<String> settingsString;
+
+    DBLatencyThresholdsAndWatcher(String config, TraceModuleProvider provider) {
+        super(TraceModule.NAME, provider, "slowDBAccessThreshold");
+        thresholds = new AtomicReference(new HashMap<>());
+        settingsString = new AtomicReference<>("");
+
+        activeSetting(config);
+    }
+
+    private void activeSetting(String config) {
+        Map<String, Integer> newThresholds = new HashMap<>();
+        String[] settings = config.split(",");
+        for (String setting : settings) {
+            String[] typeValue = setting.split(":");
+            if (typeValue.length == 2) {
+                newThresholds.put(typeValue[0].trim().toLowerCase(), Integer.parseInt(typeValue[1].trim()));
+            }
+        }
+        if (!newThresholds.containsKey("default")) {
+            newThresholds.put("default", 10000);
+        }
+
+        thresholds.set(newThresholds);
+        settingsString.set(config);
+    }
+
+    public int getThreshold(String type) {
+        type = type.toLowerCase();
+        if (thresholds.get().containsKey(type)) {
+            return thresholds.get().get(type);
+        } else {
+            return thresholds.get().get("default");
+        }
+    }
+
+    @Override public void notify(ConfigChangeEvent value) {
+        if (EventType.DELETE.equals(value.getEventType())) {
+            activeSetting("");
+        } else {
+            activeSetting(value.getNewValue());
+        }
+    }
+
+    @Override public String value() {
+        return settingsString.get();
+    }
+}

oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/receiver/trace/provider/TraceModuleProvider.java

@@ -19,6 +19,7 @@
 package org.apache.skywalking.oap.server.receiver.trace.provider;
 
 import java.io.IOException;
+import org.apache.skywalking.oap.server.configuration.api.*;
 import org.apache.skywalking.oap.server.core.CoreModule;
 import org.apache.skywalking.oap.server.core.server.*;
 import org.apache.skywalking.oap.server.library.module.*;
@@ -42,6 +43,7 @@ public class TraceModuleProvider extends ModuleProvider {
     private final TraceServiceModuleConfig moduleConfig;
     private SegmentParse.Producer segmentProducer;
     private SegmentParseV2.Producer segmentProducerV2;
+    private DBLatencyThresholdsAndWatcher thresholds;
 
     public TraceModuleProvider() {
         this.moduleConfig = new TraceServiceModuleConfig();
@@ -60,7 +62,9 @@ public class TraceModuleProvider extends ModuleProvider {
     }
 
     @Override public void prepare() throws ServiceNotProvidedException {
-        moduleConfig.setDbLatencyThresholds(new DBLatencyThresholds(moduleConfig.getSlowDBAccessThreshold()));
+        thresholds = new DBLatencyThresholdsAndWatcher(moduleConfig.getSlowDBAccessThreshold(), this);
+
+        moduleConfig.setDbLatencyThresholdsAndWatcher(thresholds);
 
         SegmentParserListenerManager listenerManager = new SegmentParserListenerManager();
         if (moduleConfig.isTraceAnalysis()) {
@@ -84,9 +88,11 @@ public class TraceModuleProvider extends ModuleProvider {
     }
 
     @Override public void start() throws ModuleStartException {
+        DynamicConfigurationService dynamicConfigurationService = getManager().find(ConfigurationModule.NAME).provider().getService(DynamicConfigurationService.class);
         GRPCHandlerRegister grpcHandlerRegister = getManager().find(SharingServerModule.NAME).provider().getService(GRPCHandlerRegister.class);
         JettyHandlerRegister jettyHandlerRegister = getManager().find(SharingServerModule.NAME).provider().getService(JettyHandlerRegister.class);
         try {
+            dynamicConfigurationService.registerConfigChangeWatcher(thresholds);
 
             grpcHandlerRegister.addHandler(new TraceSegmentServiceHandler(segmentProducer));
             grpcHandlerRegister.addHandler(new TraceSegmentReportServiceHandler(segmentProducerV2, getManager()));
@@ -111,6 +117,6 @@ public class TraceModuleProvider extends ModuleProvider {
     }
 
     @Override public String[] requiredModules() {
-        return new String[] {TelemetryModule.NAME, CoreModule.NAME, SharingServerModule.NAME};
+        return new String[] {TelemetryModule.NAME, CoreModule.NAME, SharingServerModule.NAME, ConfigurationModule.NAME};
     }
 }

oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/receiver/trace/provider/TraceServiceModuleConfig.java

@@ -38,7 +38,7 @@ public class TraceServiceModuleConfig extends ModuleConfig {
      * The threshold used to check the slow database access. Unit, millisecond.
      */
     @Setter @Getter private String slowDBAccessThreshold = "default:200";
-    @Setter @Getter private DBLatencyThresholds dbLatencyThresholds;
+    @Setter @Getter private DBLatencyThresholdsAndWatcher dbLatencyThresholdsAndWatcher;
     /**
      * Analysis trace status.
      *

oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/main/java/org/apache/skywalking/oap/server/receiver/trace/provider/parser/listener/endpoint/MultiScopesSpanListener.java

@@ -165,7 +165,7 @@ public class MultiScopesSpanListener implements EntrySpanListener, ExitSpanListe
 
                 } else if (SpanTags.DB_TYPE.equals(tag.getKey())) {
                     String dbType = tag.getValue();
-                    DBLatencyThresholds thresholds = config.getDbLatencyThresholds();
+                    DBLatencyThresholdsAndWatcher thresholds = config.getDbLatencyThresholdsAndWatcher();
                     int threshold = thresholds.getThreshold(dbType);
                     if (sourceBuilder.getLatency() > threshold) {
                         isSlowDBAccess = true;

oap-server/server-starter/pom.xml

@@ -171,6 +171,13 @@
             <artifactId>exporter</artifactId>
             <version>${project.version}</version>
         </dependency>
+
+        <!-- configuration -->
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>grpc-configuration-sync</artifactId>
+            <version>${project.version}</version>
+        </dependency>
     </dependencies>
     <build>
         <finalName>skywalking-oap</finalName>

oap-server/server-starter/src/main/assembly/application.yml

@@ -123,6 +123,8 @@ alarm:
   default:
 telemetry:
   none:
+configuration:
+  none:
 #exporter:
 #  grpc:
 #    targetHost: ${SW_EXPORTER_GRPC_HOST:127.0.0.1}

oap-server/server-starter/src/main/resources/application.yml

@@ -129,6 +129,8 @@ telemetry:
   prometheus:
     host: ${SW_TELEMETRY_PROMETHEUS_HOST:0.0.0.0}
     port: ${SW_TELEMETRY_PROMETHEUS_PORT:1234}
+configuration:
+  none:
 #exporter:
 #  grpc:
 #    targetHost: ${SW_EXPORTER_GRPC_HOST:127.0.0.1}

pom.xml

@@ -485,7 +485,8 @@
                                 org/apache/skywalking/apm/network/language/**/*.java,
                                 org/apache/skywalking/oap/server/core/remote/grpc/proto/*.java,
                                 org/apache/skywalking/oal/tool/grammar/*.java,
-                                org/apache/skywalking/oap/server/exporter/grpc/*.java
+                                org/apache/skywalking/oap/server/exporter/grpc/*.java,
+                                org/apache/skywalking/oap/server/configuration/service/*.java
                             </excludes>
                         </configuration>
                         <goals>