Provide a lazily constructed default executor for the ones using the deprecated APIs.

1 files changed, 33 insertions, 6 deletions

diff --git a/container-search/src/main/java/com/yahoo/search/searchchain/AsyncExecution.java b/container-search/src/main/java/com/yahoo/search/searchchain/AsyncExecution.java
index c1d8972bae4..f6d95e01ed8 100644
--- a/container-search/src/main/java/com/yahoo/search/searchchain/AsyncExecution.java
+++ b/container-search/src/main/java/com/yahoo/search/searchchain/AsyncExecution.java
@@ -2,7 +2,7 @@
 package com.yahoo.search.searchchain;
 
 import com.yahoo.component.chain.Chain;
-import com.yahoo.concurrent.InThreadExecutorService;
+import com.yahoo.concurrent.ThreadFactoryFactory;
 import com.yahoo.search.Query;
 import com.yahoo.search.Result;
 import com.yahoo.search.Searcher;
@@ -16,8 +16,11 @@ import java.util.concurrent.Executor;
 import java.util.concurrent.Future;
 import java.util.concurrent.FutureTask;
 import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.SynchronousQueue;
+import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
+import java.util.concurrent.atomic.AtomicReference;
 
 /**
  * Provides asynchronous execution of searchchains.
@@ -49,8 +52,32 @@ import java.util.concurrent.TimeoutException;
  * @see com.yahoo.search.searchchain.Execution
  * @author Arne Bergene Fossaa
  */
-//TODO Make package private as this is intended for use with FederationSearcher only.
 public class AsyncExecution {
+    private static final AtomicReference<Executor> deprecatedExecutor = new AtomicReference<>(null);
+
+    private static Executor createDeprecatedExecutor() {
+        int numCpus = Runtime.getRuntime().availableProcessors();
+        ThreadPoolExecutor executor = new ThreadPoolExecutor(2*numCpus, numCpus*10, 1L, TimeUnit.SECONDS,
+                new SynchronousQueue<>(false), ThreadFactoryFactory.getThreadFactory("search"));
+        // Prestart needed, if not all threads will be created by the fist N tasks and hence they might also
+        // get the dreaded thread locals initialized even if they will never run.
+        // That counters what we we want to achieve with the Q that will prefer thread locality.
+        executor.prestartAllCoreThreads();
+        return executor;
+    }
+    private static Executor getDeprecatedExecutor() {
+        Executor executor = deprecatedExecutor.get();
+        if (executor == null) {
+            synchronized (deprecatedExecutor) {
+                executor = deprecatedExecutor.get();
+                if (executor == null) {
+                    executor = createDeprecatedExecutor();
+                    deprecatedExecutor.set(executor);
+                }
+            }
+        }
+        return executor;
+    }
 
     /** The execution this executes */
     private final Execution execution;
@@ -116,7 +143,7 @@ public class AsyncExecution {
     }
     @Deprecated
     public FutureResult search(Query query) {
-        return search(query, new InThreadExecutorService());
+        return search(query, getDeprecatedExecutor());
     }
 
     public FutureResult searchAndFill(Query query, Executor executor) {
@@ -128,7 +155,7 @@ public class AsyncExecution {
     }
     @Deprecated
     public FutureResult searchAndFill(Query query) {
-        return searchAndFill(query, new InThreadExecutorService());
+        return searchAndFill(query, getDeprecatedExecutor());
     }
 
     /**
@@ -144,7 +171,7 @@ public class AsyncExecution {
     }
     @Deprecated
     public FutureResult fill(Result result, String summaryClass) {
-        return fill(result, summaryClass, new InThreadExecutorService());
+        return fill(result, summaryClass, getDeprecatedExecutor());
     }
 
     private static <T> Future<T> getFuture(Executor executor, Callable<T> callable) {
@@ -208,7 +235,7 @@ public class AsyncExecution {
     }
     @Deprecated
     public static List<Result> waitForAll(Collection<FutureResult> tasks, long timeoutMs) {
-        return waitForAll(tasks, timeoutMs, new InThreadExecutorService());
+        return waitForAll(tasks, timeoutMs, getDeprecatedExecutor());
     }
 
 }