1 files changed, 63 insertions, 0 deletions
diff --git a/container-core/src/main/java/com/yahoo/container/handler/threadpool/WorkerCompletionTimingThreadPoolExecutor.java b/container-core/src/main/java/com/yahoo/container/handler/threadpool/WorkerCompletionTimingThreadPoolExecutor.java
new file mode 100644
index 00000000000..9742e7ecfc3
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/container/handler/threadpool/WorkerCompletionTimingThreadPoolExecutor.java
@@ -0,0 +1,63 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.container.handler.threadpool;
+
+import com.yahoo.jdisc.Metric;
+
+import java.util.Map;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * A thread pool executor which maintains the last time a worker completed
+ * package private for testing
+ *
+ * @author Steinar Knutsen
+ * @author baldersheim
+ * @author bratseth
+ */
+class WorkerCompletionTimingThreadPoolExecutor extends ThreadPoolExecutor {
+
+    private static final String UNHANDLED_EXCEPTIONS_METRIC = "jdisc.thread_pool.unhandled_exceptions";
+
+    volatile long lastThreadAssignmentTimeMillis = System.currentTimeMillis();
+    private final AtomicLong startedCount = new AtomicLong(0);
+    private final AtomicLong completedCount = new AtomicLong(0);
+    private final Metric metric;
+
+    WorkerCompletionTimingThreadPoolExecutor(
+            int corePoolSize,
+            int maximumPoolSize,
+            long keepAliveTime,
+            TimeUnit unit,
+            BlockingQueue<Runnable> workQueue,
+            ThreadFactory threadFactory,
+            Metric metric) {
+        super(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, threadFactory);
+        this.metric = metric;
+    }
+
+    @Override
+    protected void beforeExecute(Thread t, Runnable r) {
+        super.beforeExecute(t, r);
+        lastThreadAssignmentTimeMillis = System.currentTimeMillis();
+        startedCount.incrementAndGet();
+    }
+
+    @Override
+    protected void afterExecute(Runnable r, Throwable t) {
+        super.afterExecute(r, t);
+        completedCount.incrementAndGet();
+        if (t != null) {
+            metric.add(UNHANDLED_EXCEPTIONS_METRIC, 1L, metric.createContext(Map.of("exception", t.getClass().getSimpleName())));
+        }
+    }
+
+    @Override
+    public int getActiveCount() {
+        return (int)(startedCount.get() - completedCount.get());
+    }
+}
+