Fixes #8863 - Provide a possibility to name virtual threads (#8903)

* Fixes #8863 - Provide a possibility to name virtual threads Reworked the VirtualThreads APIs to be based on `Executor` rather than just `boolean`. Introduced Jetty module `threadpool-virtual-preview`. Signed-off-by: Simone Bordet <[email protected]>
jetty · Nov 21, 2022 · 83154b4 · 83154b4
1 parent 88ea1e8
commit 83154b4
Show file tree

Hide file tree

Showing 11 changed files with 229 additions and 43 deletions.
diff --git a/jetty-http-spi/src/main/java/org/eclipse/jetty/http/spi/DelegatingThreadPool.java b/jetty-http-spi/src/main/java/org/eclipse/jetty/http/spi/DelegatingThreadPool.java
@@ -63,16 +63,16 @@ public boolean tryExecute(Runnable task)
     }
 
     @Override
-    public boolean isUseVirtualThreads()
+    public Executor getVirtualThreadsExecutor()
     {
-        return VirtualThreads.isUseVirtualThreads(_executor);
+        return VirtualThreads.getVirtualThreadsExecutor(_executor);
     }
 
     @Override
-    public void setUseVirtualThreads(boolean useVirtualThreads)
+    public void setVirtualThreadsExecutor(Executor executor)
     {
         if (_executor instanceof VirtualThreads.Configurable)
-            ((VirtualThreads.Configurable)_executor).setUseVirtualThreads(useVirtualThreads);
+            ((VirtualThreads.Configurable)_executor).setVirtualThreadsExecutor(executor);
     }
 
     @Override

diff --git a/jetty-server/src/main/config/etc/jetty-threadpool-virtual-preview.xml b/jetty-server/src/main/config/etc/jetty-threadpool-virtual-preview.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0"?>
+<!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "https://www.eclipse.org/jetty/configure_10_0.dtd">
+
+<Configure>
+  <New id="threadPool" class="org.eclipse.jetty.util.thread.QueuedThreadPool">
+    <Set name="name" property="jetty.threadPool.namePrefix" />
+    <Set name="minThreads" type="int"><Property name="jetty.threadPool.minThreads" deprecated="threads.min" default="10"/></Set>
+    <Set name="maxThreads" type="int"><Property name="jetty.threadPool.maxThreads" deprecated="threads.max" default="200"/></Set>
+    <Set name="reservedThreads" type="int"><Property name="jetty.threadPool.reservedThreads" default="-1"/></Set>
+    <Set name="idleTimeout" type="int"><Property name="jetty.threadPool.idleTimeout" deprecated="threads.timeout" default="60000"/></Set>
+    <Set name="detailedDump" type="boolean"><Property name="jetty.threadPool.detailedDump" default="false"/></Set>
+    <Get id="namePrefix" name="name" />
+    <Call class="java.lang.Thread" name="ofVirtual">
+      <Call class="java.lang.Thread$Builder" name="name">
+        <Arg>
+          <Property name="jetty.threadPool.virtual.namePrefix">
+            <Default><Ref refid="namePrefix" />-virtual-</Default>
+          </Property>
+        </Arg>
+        <Arg type="long">0</Arg>
+        <Call class="java.lang.Thread$Builder" name="allowSetThreadLocals">
+          <Arg type="boolean"><Property name="jetty.threadPool.virtual.allowSetThreadLocals" default="true" /></Arg>
+          <Call class="java.lang.Thread$Builder" name="inheritInheritableThreadLocals">
+            <Arg type="boolean"><Property name="jetty.threadPool.virtual.inheritInheritableThreadLocals" default="false" /></Arg>
+            <Call id="virtualThreadFactory" class="java.lang.Thread$Builder" name="factory" />
+          </Call>
+        </Call>
+      </Call>
+    </Call>
+    <Call name="setVirtualThreadsExecutor">
+      <Arg>
+        <Call class="java.util.concurrent.Executors" name="newThreadPerTaskExecutor">
+          <Arg><Ref refid="virtualThreadFactory" /></Arg>
+        </Call>
+      </Arg>
+    </Call>
+  </New>
+
+  <Call class="org.slf4j.LoggerFactory" name="getLogger">
+    <Arg>org.eclipse.jetty</Arg>
+    <Call name="warn">
+      <Arg>Virtual threads are a Java Preview Feature, support may be limited.</Arg>
+    </Call>
+  </Call>
+</Configure>
diff --git a/jetty-server/src/main/config/etc/jetty-threadpool.xml b/jetty-server/src/main/config/etc/jetty-threadpool.xml
@@ -20,10 +20,11 @@
   <!-- for all configuration that may be set here.                 -->
   <!-- =========================================================== -->
   <New id="threadPool" class="org.eclipse.jetty.util.thread.QueuedThreadPool">
+    <Set name="name" property="jetty.threadPool.namePrefix" />
     <Set name="minThreads" type="int"><Property name="jetty.threadPool.minThreads" deprecated="threads.min" default="10"/></Set>
     <Set name="maxThreads" type="int"><Property name="jetty.threadPool.maxThreads" deprecated="threads.max" default="200"/></Set>
     <Set name="reservedThreads" type="int"><Property name="jetty.threadPool.reservedThreads" default="-1"/></Set>
-    <Set name="useVirtualThreads" type="boolean"><Property name="jetty.threadPool.useVirtualThreads" default="false"/></Set>
+    <Set name="useVirtualThreads" type="boolean"><Property deprecated="jetty.threadPool.useVirtualThreads" default="false"/></Set>
     <Set name="idleTimeout" type="int"><Property name="jetty.threadPool.idleTimeout" deprecated="threads.timeout" default="60000"/></Set>
     <Set name="detailedDump" type="boolean"><Property name="jetty.threadPool.detailedDump" default="false"/></Set>
   </New>

diff --git a/jetty-server/src/main/config/modules/threadpool-virtual-preview.mod b/jetty-server/src/main/config/modules/threadpool-virtual-preview.mod
@@ -0,0 +1,42 @@
+[description]
+Enables and configures the Server ThreadPool with support for virtual threads.
+
+[exec]
+--enable-preview
+
+[depends]
+logging
+
+[provides]
+threadpool
+
+[xml]
+etc/jetty-threadpool-virtual-preview.xml
+
+[ini-template]
+## Platform threads name prefix.
+#jetty.threadPool.namePrefix=qtp<hashCode>
+
+## Minimum number of pooled threads.
+#jetty.threadPool.minThreads=10
+
+## Maximum number of pooled threads.
+#jetty.threadPool.maxThreads=200
+
+## Number of reserved threads (-1 for heuristic).
+#jetty.threadPool.reservedThreads=-1
+
+## Thread idle timeout (in milliseconds).
+#jetty.threadPool.idleTimeout=60000
+
+## Whether to output a detailed dump.
+#jetty.threadPool.detailedDump=false
+
+## Virtual threads name prefix.
+#jetty.threadPool.virtual.namePrefix=qtp<hashCode>-virtual-
+
+## Whether virtual threads are allowed to set thread locals.
+#jetty.threadPool.virtual.allowSetThreadLocals=true
+
+## Whether virtual threads inherits the values of inheritable thread locals.
+#jetty.threadPool.virtual.allowSetThreadLocals=true
diff --git a/jetty-server/src/main/config/modules/threadpool.mod b/jetty-server/src/main/config/modules/threadpool.mod
@@ -4,10 +4,16 @@ Enables and configures the Server ThreadPool.
 [depends]
 logging
 
+[provides]
+threadpool|default
+
 [xml]
 etc/jetty-threadpool.xml
 
 [ini-template]
+## Thread name prefix.
+#jetty.threadPool.namePrefix=qtp<hashCode>
+
 ## Minimum number of pooled threads.
 #jetty.threadPool.minThreads=10
 
@@ -18,6 +24,7 @@ etc/jetty-threadpool.xml
 #jetty.threadPool.reservedThreads=-1
 
 ## Whether to use virtual threads, if the runtime supports them.
+## Deprecated, use Jetty module 'threadpool-virtual-preview' instead.
 #jetty.threadPool.useVirtualThreads=false
 
 ## Thread idle timeout (in milliseconds).

diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/VirtualThreads.java b/jetty-util/src/main/java/org/eclipse/jetty/util/VirtualThreads.java
@@ -25,7 +25,7 @@
  * and, if virtual threads are supported, to start virtual threads.</p>
  *
  * @see #areSupported()
- * @see #executeOnVirtualThread(Runnable)
+ * @see #getVirtualThreadsExecutor(Executor)
  * @see #isVirtualThread()
  */
 public class VirtualThreads
@@ -58,6 +58,11 @@ private static Method probeIsVirtualThread()
         }
     }
 
+    private static Method getIsVirtualThreadMethod()
+    {
+        return isVirtualThread;
+    }
+
     private static void warn()
     {
         LOG.warn("Virtual thread support is not available (or not enabled via --enable-preview) in the current Java runtime ({})", System.getProperty("java.version"));
@@ -78,14 +83,16 @@ public static boolean areSupported()
      *
      * @param task the task to execute in a virtual thread
      * @see #areSupported()
+     * @deprecated use {@link #getVirtualThreadsExecutor(Executor)} instead
      */
+    @Deprecated(forRemoval = true)
     public static void executeOnVirtualThread(Runnable task)
     {
         try
         {
             if (LOG.isDebugEnabled())
                 LOG.debug("Starting in virtual thread: {}", task);
-            executor.execute(task);
+            getDefaultVirtualThreadsExecutor().execute(task);
         }
         catch (Throwable x)
         {
@@ -101,7 +108,7 @@ public static boolean isVirtualThread()
     {
         try
         {
-            return (Boolean)isVirtualThread.invoke(Thread.currentThread());
+            return (Boolean)getIsVirtualThreadMethod().invoke(Thread.currentThread());
         }
         catch (Throwable x)
         {
@@ -110,6 +117,25 @@ public static boolean isVirtualThread()
         }
     }
 
+    /**
+     * @return a default virtual thread per task {@code Executor}
+     */
+    public static Executor getDefaultVirtualThreadsExecutor()
+    {
+        return executor;
+    }
+
+    /**
+     * @param executor the {@code Executor} to obtain a virtual threads {@code Executor} from
+     * @return a virtual threads {@code Executor} obtained from the given {@code Executor}
+     */
+    public static Executor getVirtualThreadsExecutor(Executor executor)
+    {
+        if (executor instanceof Configurable)
+            return ((Configurable)executor).getVirtualThreadsExecutor();
+        return null;
+    }
+
     /**
      * <p>Tests whether the given executor implements {@link Configurable} and
      * it has been configured to use virtual threads.</p>
@@ -121,39 +147,62 @@ public static boolean isVirtualThread()
     public static boolean isUseVirtualThreads(Executor executor)
     {
         if (executor instanceof Configurable)
-            return ((Configurable)executor).isUseVirtualThreads();
+            return ((Configurable)executor).getVirtualThreadsExecutor() != null;
         return false;
     }
 
     /**
      * <p>Implementations of this interface can be configured to use virtual threads.</p>
      * <p>Whether virtual threads are actually used depends on whether the runtime
      * supports virtual threads and, if the runtime supports them, whether they are
-     * configured to be used via {@link #setUseVirtualThreads(boolean)}.</p>
+     * configured to be used via {@link #setVirtualThreadsExecutor(Executor)}.</p>
      */
     public interface Configurable
     {
         /**
-         * @return whether to use virtual threads
+         * @return the {@code Executor} to use to execute tasks in virtual threads
          */
-        default boolean isUseVirtualThreads()
+        default Executor getVirtualThreadsExecutor()
         {
-            return false;
+            return null;
         }
 
         /**
-         * @param useVirtualThreads whether to use virtual threads
+         *
+         * @param executor the {@code Executor} to use to execute tasks in virtual threads
          * @throws UnsupportedOperationException if the runtime does not support virtual threads
          * @see #areSupported()
          */
-        default void setUseVirtualThreads(boolean useVirtualThreads)
+        default void setVirtualThreadsExecutor(Executor executor)
         {
-            if (useVirtualThreads && !VirtualThreads.areSupported())
+            if (executor != null && !VirtualThreads.areSupported())
             {
                 warn();
                 throw new UnsupportedOperationException();
             }
         }
+
+        /**
+         * @return whether to use virtual threads
+         * @deprecated use {@link #getVirtualThreadsExecutor()} instead
+         */
+        @Deprecated(forRemoval = true)
+        default boolean isUseVirtualThreads()
+        {
+            return getVirtualThreadsExecutor() != null;
+        }
+
+        /**
+         * @param useVirtualThreads whether to use virtual threads
+         * @throws UnsupportedOperationException if the runtime does not support virtual threads
+         * @see #areSupported()
+         * @deprecated use {@link #setVirtualThreadsExecutor(Executor)} instead
+         */
+        @Deprecated(forRemoval = true)
+        default void setUseVirtualThreads(boolean useVirtualThreads)
+        {
+            setVirtualThreadsExecutor(useVirtualThreads ? executor : null);
+        }
     }
 
     private VirtualThreads()

diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/thread/ExecutorThreadPool.java b/jetty-util/src/main/java/org/eclipse/jetty/util/thread/ExecutorThreadPool.java
@@ -18,6 +18,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.Executor;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
@@ -47,7 +48,7 @@ public class ExecutorThreadPool extends ContainerLifeCycle implements ThreadPool
     private int _priority = Thread.NORM_PRIORITY;
     private boolean _daemon;
     private boolean _detailedDump;
-    private boolean _useVirtualThreads;
+    private Executor _virtualThreadsExecutor;
 
     public ExecutorThreadPool()
     {
@@ -271,18 +272,18 @@ public boolean isLowOnThreads()
     }
 
     @Override
-    public boolean isUseVirtualThreads()
+    public Executor getVirtualThreadsExecutor()
     {
-        return _useVirtualThreads;
+        return _virtualThreadsExecutor;
     }
 
     @Override
-    public void setUseVirtualThreads(boolean useVirtualThreads)
+    public void setVirtualThreadsExecutor(Executor executor)
     {
         try
         {
-            VirtualThreads.Configurable.super.setUseVirtualThreads(useVirtualThreads);
-            _useVirtualThreads = useVirtualThreads;
+            VirtualThreads.Configurable.super.setVirtualThreadsExecutor(executor);
+            _virtualThreadsExecutor = executor;
         }
         catch (UnsupportedOperationException ignored)
         {

diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/thread/QueuedThreadPool.java b/jetty-util/src/main/java/org/eclipse/jetty/util/thread/QueuedThreadPool.java
@@ -20,6 +20,7 @@
 import java.util.Set;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executor;
 import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.TimeUnit;
@@ -111,7 +112,7 @@ public class QueuedThreadPool extends ContainerLifeCycle implements ThreadFactor
     private int _lowThreadsThreshold = 1;
     private ThreadPoolBudget _budget;
     private long _stopTimeout;
-    private boolean _useVirtualThreads;
+    private Executor _virtualThreadsExecutor;
 
     public QueuedThreadPool()
     {
@@ -515,18 +516,18 @@ public void setLowThreadsThreshold(int lowThreadsThreshold)
     }
 
     @Override
-    public boolean isUseVirtualThreads()
+    public Executor getVirtualThreadsExecutor()
     {
-        return _useVirtualThreads;
+        return _virtualThreadsExecutor;
     }
 
     @Override
-    public void setUseVirtualThreads(boolean useVirtualThreads)
+    public void setVirtualThreadsExecutor(Executor executor)
     {
         try
         {
-            VirtualThreads.Configurable.super.setUseVirtualThreads(useVirtualThreads);
-            _useVirtualThreads = useVirtualThreads;
+            VirtualThreads.Configurable.super.setVirtualThreadsExecutor(executor);
+            _virtualThreadsExecutor = executor;
         }
         catch (UnsupportedOperationException ignored)
         {