Support collecting metrics of ZGC (#89)

Co-authored-by: litexu <litexu@tencent.com>

CHANGES.md

@@ -20,6 +20,7 @@ Release Notes.
 * Fix the bug that httpasyncclient-4.x-plugin  puts the dirty tracing context in the connection context
 * Compatible with the versions after dubbo-2.7.14
 * Follow protocol grammar fix `GCPhrase -> GCPhase`.
+* Support ZGC GC time and count metric collect. (Require 9.0.0 OAP)
 
 #### Documentation
 

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/CMSGCModule.java

@@ -35,4 +35,9 @@ public class CMSGCModule extends GCModule {
     protected String getNewGCName() {
         return "ParNew";
     }
+
+    @Override
+    protected String getNormalGCName() {
+        return null;
+    }
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/G1GCModule.java

@@ -35,4 +35,9 @@ public class G1GCModule extends GCModule {
     protected String getNewGCName() {
         return "G1 Young Generation";
     }
+
+    @Override
+    protected String getNormalGCName() {
+        return null;
+    }
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/GCModule.java

@@ -31,6 +31,8 @@ public abstract class GCModule implements GCMetricAccessor {
     private long lastYGCCount = 0;
     private long lastOGCCollectionTime = 0;
     private long lastYGCCollectionTime = 0;
+    private long lastNormalGCCount = 0;
+    private long lastNormalGCTime = 0;
 
     public GCModule(List<GarbageCollectorMXBean> beans) {
         this.beans = beans;
@@ -62,6 +64,15 @@ public abstract class GCModule implements GCMetricAccessor {
                 long time = bean.getCollectionTime();
                 gcTime = time - lastOGCCollectionTime;
                 lastOGCCollectionTime = time;
+            } else if (name.equals(getNormalGCName())) {
+                phase = GCPhase.NORMAL;
+                long collectionCount = bean.getCollectionCount();
+                gcCount = collectionCount - lastNormalGCCount;
+                lastNormalGCCount = collectionCount;
+
+                long time = bean.getCollectionTime();
+                gcTime = time - lastNormalGCTime;
+                lastNormalGCTime = time;
             } else {
                 continue;
             }
@@ -75,4 +86,6 @@ public abstract class GCModule implements GCMetricAccessor {
     protected abstract String getOldGCName();
 
     protected abstract String getNewGCName();
+
+    protected abstract String getNormalGCName();
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/GCProvider.java

@@ -62,6 +62,9 @@ public enum GCProvider {
         } else if (name.equals("MarkSweepCompact")) {
             // Serial collector ( -XX:+UseSerialGC )
             return new SerialGCModule(beans);
+        } else if (name.indexOf("ZGC") > -1) {
+            // Serial collector ( -XX:+UseZGC )
+            return new ZGCModule(beans);
         } else {
             // Unknown
             return null;

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/ParallelGCModule.java

@@ -36,4 +36,9 @@ public class ParallelGCModule extends GCModule {
         return "PS Scavenge";
     }
 
+    @Override
+    protected String getNormalGCName() {
+        return null;
+    }
+
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/SerialGCModule.java

@@ -35,4 +35,9 @@ public class SerialGCModule extends GCModule {
     protected String getNewGCName() {
         return "Copy";
     }
+
+    @Override
+    protected String getNormalGCName() {
+        return null;
+    }
 }

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/jvm/gc/ZGCModule.java

@@ -0,0 +1,44 @@
+/*
+ * 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.apm.agent.core.jvm.gc;
+
+import java.lang.management.GarbageCollectorMXBean;
+import java.util.List;
+
+public class ZGCModule extends GCModule {
+
+    public ZGCModule(List<GarbageCollectorMXBean> beans) {
+        super(beans);
+    }
+
+    @Override
+    protected String getOldGCName() {
+        return null;
+    }
+
+    @Override
+    protected String getNewGCName() {
+        return null;
+    }
+
+    @Override
+    protected String getNormalGCName() {
+        return "ZGC";
+    }
+}