Create a Builder for TaskTrackingConfig (#130961)

server/src/main/java/org/elasticsearch/common/util/concurrent/EsExecutors.java

@@ -577,6 +577,7 @@ public class EsExecutors {
     }
 
     public static class TaskTrackingConfig {
+        // This is a random starting point alpha.
         public static final double DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST = 0.3;
 
         private final boolean trackExecutionTime;
@@ -597,17 +598,6 @@ public class EsExecutors {
             DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST
         );
 
-        public TaskTrackingConfig(boolean trackOngoingTasks, double executionTimeEWMAAlpha) {
-            this(true, trackOngoingTasks, false, executionTimeEWMAAlpha);
-        }
-
-        /**
-         * Execution tracking enabled constructor, with extra options to enable further specialized tracking.
-         */
-        public TaskTrackingConfig(boolean trackOngoingTasks, boolean trackMaxQueueLatency, double executionTimeEwmaAlpha) {
-            this(true, trackOngoingTasks, trackMaxQueueLatency, executionTimeEwmaAlpha);
-        }
-
         /**
          * @param trackExecutionTime Whether to track execution stats
          * @param trackOngoingTasks Whether to track ongoing task execution time, not just finished tasks
@@ -641,6 +631,39 @@ public class EsExecutors {
         public double getExecutionTimeEwmaAlpha() {
             return executionTimeEwmaAlpha;
         }
+
+        public static Builder builder() {
+            return new Builder();
+        }
+
+        public static class Builder {
+            private boolean trackExecutionTime = false;
+            private boolean trackOngoingTasks = false;
+            private boolean trackMaxQueueLatency = false;
+            private double ewmaAlpha = DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST;
+
+            public Builder() {}
+
+            public Builder trackExecutionTime(double alpha) {
+                trackExecutionTime = true;
+                ewmaAlpha = alpha;
+                return this;
+            }
+
+            public Builder trackOngoingTasks() {
+                trackOngoingTasks = true;
+                return this;
+            }
+
+            public Builder trackMaxQueueLatency() {
+                trackMaxQueueLatency = true;
+                return this;
+            }
+
+            public TaskTrackingConfig build() {
+                return new TaskTrackingConfig(trackExecutionTime, trackOngoingTasks, trackMaxQueueLatency, ewmaAlpha);
+            }
+        }
     }
 
 }

server/src/main/java/org/elasticsearch/threadpool/DefaultBuiltInExecutorBuilders.java

@@ -56,7 +56,11 @@ public class DefaultBuiltInExecutorBuilders implements BuiltInExecutorBuilders {
                 allocatedProcessors,
                 // 10,000 for all nodes with 8 cores or fewer. Scale up once we have more than 8 cores.
                 Math.max(allocatedProcessors * 750, 10000),
-                new EsExecutors.TaskTrackingConfig(true, true, indexAutoscalingEWMA)
+                EsExecutors.TaskTrackingConfig.builder()
+                    .trackOngoingTasks()
+                    .trackMaxQueueLatency()
+                    .trackExecutionTime(indexAutoscalingEWMA)
+                    .build()
             )
         );
         int searchOrGetThreadPoolSize = ThreadPool.searchOrGetThreadPoolSize(allocatedProcessors);
@@ -81,7 +85,7 @@ public class DefaultBuiltInExecutorBuilders implements BuiltInExecutorBuilders {
                 ThreadPool.Names.SEARCH,
                 searchOrGetThreadPoolSize,
                 searchOrGetThreadPoolSize * 1000,
-                new EsExecutors.TaskTrackingConfig(true, searchAutoscalingEWMA)
+                EsExecutors.TaskTrackingConfig.builder().trackOngoingTasks().trackExecutionTime(searchAutoscalingEWMA).build()
             )
         );
         result.put(
@@ -91,7 +95,7 @@ public class DefaultBuiltInExecutorBuilders implements BuiltInExecutorBuilders {
                 ThreadPool.Names.SEARCH_COORDINATION,
                 halfProc,
                 1000,
-                new EsExecutors.TaskTrackingConfig(true, searchAutoscalingEWMA)
+                EsExecutors.TaskTrackingConfig.builder().trackOngoingTasks().trackExecutionTime(searchAutoscalingEWMA).build()
             )
         );
         result.put(
@@ -195,7 +199,7 @@ public class DefaultBuiltInExecutorBuilders implements BuiltInExecutorBuilders {
                 ThreadPool.Names.SYSTEM_WRITE,
                 halfProcMaxAt5,
                 1000,
-                new EsExecutors.TaskTrackingConfig(true, indexAutoscalingEWMA),
+                EsExecutors.TaskTrackingConfig.builder().trackOngoingTasks().trackExecutionTime(indexAutoscalingEWMA).build(),
                 true
             )
         );
@@ -228,7 +232,7 @@ public class DefaultBuiltInExecutorBuilders implements BuiltInExecutorBuilders {
                 ThreadPool.Names.SYSTEM_CRITICAL_WRITE,
                 halfProcMaxAt5,
                 1500,
-                new EsExecutors.TaskTrackingConfig(true, indexAutoscalingEWMA),
+                EsExecutors.TaskTrackingConfig.builder().trackOngoingTasks().trackExecutionTime(indexAutoscalingEWMA).build(),
                 true
             )
         );

server/src/test/java/org/elasticsearch/common/util/concurrent/EsExecutorsTests.java

@@ -675,6 +675,7 @@ public class EsExecutorsTests extends ESTestCase {
         final int max = between(min + 1, 6);
 
         {
+            var executionTimeEwma = randomDoubleBetween(0.01, 0.1, true);
             ThreadPoolExecutor pool = EsExecutors.newScaling(
                 getClass().getName() + "/" + getTestName(),
                 min,
@@ -684,7 +685,9 @@ public class EsExecutorsTests extends ESTestCase {
                 randomBoolean(),
                 EsExecutors.daemonThreadFactory("test"),
                 threadContext,
-                new EsExecutors.TaskTrackingConfig(randomBoolean(), randomDoubleBetween(0.01, 0.1, true))
+                randomBoolean()
+                    ? EsExecutors.TaskTrackingConfig.builder().trackOngoingTasks().trackExecutionTime(executionTimeEwma).build()
+                    : EsExecutors.TaskTrackingConfig.builder().trackExecutionTime(executionTimeEwma).build()
             );
             assertThat(pool, instanceOf(TaskExecutionTimeTrackingEsThreadPoolExecutor.class));
         }

server/src/test/java/org/elasticsearch/common/util/concurrent/TaskExecutionTimeTrackingEsThreadPoolExecutorTests.java

@@ -11,7 +11,6 @@ package org.elasticsearch.common.util.concurrent;
 
 import org.elasticsearch.common.metrics.ExponentialBucketHistogram;
 import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.util.concurrent.EsExecutors.TaskTrackingConfig;
 import org.elasticsearch.telemetry.InstrumentType;
 import org.elasticsearch.telemetry.Measurement;
 import org.elasticsearch.telemetry.RecordingMeterRegistry;
@@ -51,7 +50,12 @@ public class TaskExecutionTimeTrackingEsThreadPoolExecutorTests extends ESTestCa
             EsExecutors.daemonThreadFactory("queuetest"),
             new EsAbortPolicy(),
             context,
-            new TaskTrackingConfig(randomBoolean(), DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+            randomBoolean()
+                ? EsExecutors.TaskTrackingConfig.builder()
+                    .trackOngoingTasks()
+                    .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                    .build()
+                : EsExecutors.TaskTrackingConfig.builder().trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST).build()
         );
         executor.prestartAllCoreThreads();
         logger.info("--> executor: {}", executor);
@@ -109,7 +113,16 @@ public class TaskExecutionTimeTrackingEsThreadPoolExecutorTests extends ESTestCa
             EsExecutors.daemonThreadFactory("queue-latency-test"),
             new EsAbortPolicy(),
             context,
-            new TaskTrackingConfig(randomBoolean(), true, DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+            randomBoolean()
+                ? EsExecutors.TaskTrackingConfig.builder()
+                    .trackOngoingTasks()
+                    .trackMaxQueueLatency()
+                    .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                    .build()
+                : EsExecutors.TaskTrackingConfig.builder()
+                    .trackMaxQueueLatency()
+                    .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                    .build()
         );
         try {
             executor.prestartAllCoreThreads();
@@ -153,7 +166,12 @@ public class TaskExecutionTimeTrackingEsThreadPoolExecutorTests extends ESTestCa
             EsExecutors.daemonThreadFactory("queuetest"),
             new EsAbortPolicy(),
             context,
-            new TaskTrackingConfig(randomBoolean(), DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+            randomBoolean()
+                ? EsExecutors.TaskTrackingConfig.builder()
+                    .trackOngoingTasks()
+                    .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                    .build()
+                : EsExecutors.TaskTrackingConfig.builder().trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST).build()
         );
         executor.prestartAllCoreThreads();
         logger.info("--> executor: {}", executor);
@@ -185,7 +203,10 @@ public class TaskExecutionTimeTrackingEsThreadPoolExecutorTests extends ESTestCa
             EsExecutors.daemonThreadFactory("queuetest"),
             new EsAbortPolicy(),
             context,
-            new TaskTrackingConfig(true, DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+            EsExecutors.TaskTrackingConfig.builder()
+                .trackOngoingTasks()
+                .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                .build()
         );
         var taskRunningLatch = new CountDownLatch(1);
         var exitTaskLatch = new CountDownLatch(1);
@@ -220,7 +241,10 @@ public class TaskExecutionTimeTrackingEsThreadPoolExecutorTests extends ESTestCa
             EsExecutors.daemonThreadFactory("queuetest"),
             new EsAbortPolicy(),
             new ThreadContext(Settings.EMPTY),
-            new TaskTrackingConfig(true, DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+            EsExecutors.TaskTrackingConfig.builder()
+                .trackOngoingTasks()
+                .trackExecutionTime(DEFAULT_EXECUTION_TIME_EWMA_ALPHA_FOR_TEST)
+                .build()
         );
         executor.setupMetrics(meterRegistry, threadPoolName);