1 files changed, 22 insertions, 5 deletions
diff --git a/spark-common/src/main/java/me/lucko/spark/sampler/Sampler.java b/spark-common/src/main/java/me/lucko/spark/sampler/Sampler.java
index 2e8ac65..6777770 100644
--- a/spark-common/src/main/java/me/lucko/spark/sampler/Sampler.java
+++ b/spark-common/src/main/java/me/lucko/spark/sampler/Sampler.java
@@ -56,7 +56,7 @@ public class Sampler implements Runnable {
 
     /** The worker pool for inserting stack nodes */
     private final ScheduledExecutorService workerPool = Executors.newScheduledThreadPool(
-            9, new ThreadFactoryBuilder().setNameFormat("spark-worker-" + THREAD_ID.getAndIncrement() + "-%d").build()
+            6, new ThreadFactoryBuilder().setNameFormat("spark-worker-" + THREAD_ID.getAndIncrement() + "-%d").build()
     );
 
     /** The main sampling task */
@@ -123,6 +123,8 @@ public class Sampler implements Runnable {
 
     @Override
     public void run() {
+        // this is effectively synchronized, the worker pool will not allow this task
+        // to concurrently execute.
         try {
             if (this.endTime != -1 && this.endTime <= System.currentTimeMillis()) {
                 this.future.complete(this);
@@ -131,7 +133,25 @@ public class Sampler implements Runnable {
             }
 
             ThreadInfo[] threadDumps = this.threadDumper.dumpThreads(this.threadBean);
-            for (ThreadInfo threadInfo : threadDumps) {
+            this.workerPool.execute(new InsertDataTask(this.dataAggregator, threadDumps));
+        } catch (Throwable t) {
+            this.future.completeExceptionally(t);
+            cancel();
+        }
+    }
+
+    private static final class InsertDataTask implements Runnable {
+        private final DataAggregator dataAggregator;
+        private final ThreadInfo[] threadDumps;
+
+        InsertDataTask(DataAggregator dataAggregator, ThreadInfo[] threadDumps) {
+            this.dataAggregator = dataAggregator;
+            this.threadDumps = threadDumps;
+        }
+
+        @Override
+        public void run() {
+            for (ThreadInfo threadInfo : this.threadDumps) {
                 String threadName = threadInfo.getThreadName();
                 StackTraceElement[] stack = threadInfo.getStackTrace();
 
@@ -141,9 +161,6 @@ public class Sampler implements Runnable {
 
                 this.dataAggregator.insertData(threadName, stack);
             }
-        } catch (Throwable t) {
-            this.future.completeExceptionally(t);
-            cancel();
         }
     }