Make all backend thread pools daemon (alibaba#2181)

* feat：make command center thread daemon
* feat：make all NamedThreadFactory thread daemon

sentinel-cluster/sentinel-cluster-client-default/src/main/java/com/alibaba/csp/sentinel/cluster/client/NettyTransportClient.java

@@ -62,7 +62,7 @@ public class NettyTransportClient implements ClusterTransportClient {
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
     private static final ScheduledExecutorService SCHEDULER = Executors.newScheduledThreadPool(1,
-        new NamedThreadFactory("sentinel-cluster-transport-client-scheduler"));
+        new NamedThreadFactory("sentinel-cluster-transport-client-scheduler", true));
 
     public static final int RECONNECT_DELAY_MS = 2000;
 

sentinel-cluster/sentinel-cluster-server-default/src/main/java/com/alibaba/csp/sentinel/cluster/flow/statistic/concurrent/expire/RegularExpireStrategy.java

@@ -66,7 +66,7 @@ public class RegularExpireStrategy implements ExpireStrategy {
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
     private static ScheduledExecutorService executor = Executors.newScheduledThreadPool(1,
-            new NamedThreadFactory("regular clear expired token thread"));
+            new NamedThreadFactory("regular clear expired token thread", true));
 
 
     public RegularExpireStrategy(ConcurrentLinkedHashMap<Long, TokenCacheNode> localCache) {

sentinel-dashboard/src/main/java/com/alibaba/csp/sentinel/dashboard/metric/MetricFetcher.java

@@ -89,7 +89,7 @@ public class MetricFetcher {
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
     private ScheduledExecutorService fetchScheduleService = Executors.newScheduledThreadPool(1,
-        new NamedThreadFactory("sentinel-dashboard-metrics-fetch-task"));
+        new NamedThreadFactory("sentinel-dashboard-metrics-fetch-task", true));
     private ExecutorService fetchService;
     private ExecutorService fetchWorker;
 
@@ -100,10 +100,10 @@ public MetricFetcher() {
         RejectedExecutionHandler handler = new DiscardPolicy();
         fetchService = new ThreadPoolExecutor(cores, cores,
             keepAliveTime, TimeUnit.MILLISECONDS, new ArrayBlockingQueue<>(queueSize),
-            new NamedThreadFactory("sentinel-dashboard-metrics-fetchService"), handler);
+            new NamedThreadFactory("sentinel-dashboard-metrics-fetchService", true), handler);
         fetchWorker = new ThreadPoolExecutor(cores, cores,
             keepAliveTime, TimeUnit.MILLISECONDS, new ArrayBlockingQueue<>(queueSize),
-            new NamedThreadFactory("sentinel-dashboard-metrics-fetchWorker"), handler);
+            new NamedThreadFactory("sentinel-dashboard-metrics-fetchWorker",true), handler);
         IOReactorConfig ioConfig = IOReactorConfig.custom()
             .setConnectTimeout(3000)
             .setSoTimeout(3000)

sentinel-extension/sentinel-datasource-nacos/src/main/java/com/alibaba/csp/sentinel/datasource/nacos/NacosDataSource.java

@@ -47,7 +47,7 @@ public class NacosDataSource<T> extends AbstractDataSource<String, T> {
      * Single-thread pool. Once the thread pool is blocked, we throw up the old task.
      */
     private final ExecutorService pool = new ThreadPoolExecutor(1, 1, 0, TimeUnit.MILLISECONDS,
-        new ArrayBlockingQueue<Runnable>(1), new NamedThreadFactory("sentinel-nacos-ds-update"),
+        new ArrayBlockingQueue<Runnable>(1), new NamedThreadFactory("sentinel-nacos-ds-update", true),
         new ThreadPoolExecutor.DiscardOldestPolicy());
 
     private final Listener configListener;

sentinel-extension/sentinel-datasource-zookeeper/src/main/java/com/alibaba/csp/sentinel/datasource/zookeeper/ZookeeperDataSource.java

@@ -37,7 +37,7 @@ public class ZookeeperDataSource<T> extends AbstractDataSource<String, T> {
 
 
     private final ExecutorService pool = new ThreadPoolExecutor(1, 1, 0, TimeUnit.MILLISECONDS,
-            new ArrayBlockingQueue<Runnable>(1), new NamedThreadFactory("sentinel-zookeeper-ds-update"),
+            new ArrayBlockingQueue<Runnable>(1), new NamedThreadFactory("sentinel-zookeeper-ds-update", true),
             new ThreadPoolExecutor.DiscardOldestPolicy());
 
     private NodeCacheListener listener;

sentinel-transport/sentinel-transport-netty-http/src/main/java/com/alibaba/csp/sentinel/transport/command/NettyHttpCommandCenter.java

@@ -39,7 +39,7 @@ public class NettyHttpCommandCenter implements CommandCenter {
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
     private final ExecutorService pool = Executors.newSingleThreadExecutor(
-        new NamedThreadFactory("sentinel-netty-command-center-executor"));
+        new NamedThreadFactory("sentinel-netty-command-center-executor", true));
 
     @Override
     public void start() throws Exception {

sentinel-transport/sentinel-transport-simple-http/src/main/java/com/alibaba/csp/sentinel/transport/command/SimpleHttpCommandCenter.java

@@ -57,7 +57,7 @@ public class SimpleHttpCommandCenter implements CommandCenter {
 
     @SuppressWarnings("PMD.ThreadPoolCreationRule")
     private ExecutorService executor = Executors.newSingleThreadExecutor(
-        new NamedThreadFactory("sentinel-command-center-executor"));
+        new NamedThreadFactory("sentinel-command-center-executor", true));
     private ExecutorService bizExecutor;
 
     private ServerSocket socketReference;
@@ -75,7 +75,7 @@ public void start() throws Exception {
         int nThreads = Runtime.getRuntime().availableProcessors();
         this.bizExecutor = new ThreadPoolExecutor(nThreads, nThreads, 0L, TimeUnit.MILLISECONDS,
             new ArrayBlockingQueue<Runnable>(10),
-            new NamedThreadFactory("sentinel-command-center-service-executor"),
+            new NamedThreadFactory("sentinel-command-center-service-executor", true),
             new RejectedExecutionHandler() {
                 @Override
                 public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {