From cfce3dd0e573796ff3bd7297362580d90abfcceb Mon Sep 17 00:00:00 2001
From: Andriy Dmytruk <andriy.dmytruk@oracle.com>
Date: Mon, 29 Apr 2024 10:39:36 -0400
Subject: [PATCH] Do not parallelize definition building if it gives no
 advantage

For the cases when there are 1 or 2 cores the fork join pool is of size 1 and therefore does not achieve parallelized execution. For this case we can load definitions on the main thread.
---
 .../main/java/io/micronaut/core/io/service/ServiceScanner.java  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/src/main/java/io/micronaut/core/io/service/ServiceScanner.java b/core/src/main/java/io/micronaut/core/io/service/ServiceScanner.java
index f122f8629af..4bca150cd90 100644
--- a/core/src/main/java/io/micronaut/core/io/service/ServiceScanner.java
+++ b/core/src/main/java/io/micronaut/core/io/service/ServiceScanner.java
@@ -239,7 +239,7 @@ public void collect(Collection<S> values) {
 
         @Override
         public void collect(Collection<S> values, boolean allowFork) {
-            if (allowFork) {
+            if (allowFork && ForkJoinPool.getCommonPoolParallelism() > 1) {
                 ForkJoinPool.commonPool().invoke(this);
                 for (RecursiveActionValuesCollector<S> task : tasks) {
                     task.join();