Set netty system properties in BuildPlugin (#45881)

Currently in production instances of Elasticsearch we set a couple of
system properties by default. We currently do not apply all of these
system properties in tests. This commit applies these properties in the
tests.

buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy

@@ -901,6 +901,12 @@ class BuildPlugin implements Plugin<Project> {
                 // TODO: remove this once cname is prepended to transport.publish_address by default in 8.0
                 test.systemProperty 'es.transport.cname_in_publish_address', 'true'
 
+                // Set netty system properties to the properties we configure in jvm.options
+                test.systemProperty('io.netty.noUnsafe', 'true')
+                test.systemProperty('io.netty.noKeySetOptimization', 'true')
+                test.systemProperty('io.netty.recycler.maxCapacityPerThread', '0')
+                test.systemProperty('io.netty.allocator.numDirectArenas', '0')
+
                 test.testLogging { TestLoggingContainer logging ->
                     logging.showExceptions = true
                     logging.showCauses = true

modules/transport-netty4/build.gradle

@@ -54,9 +54,6 @@ test {
      * other if we allow them to set the number of available processors as it's set-once in Netty.
      */
     systemProperty 'es.set.netty.runtime.available.processors', 'false'
-
-    // Disable direct buffer pooling as it is disabled by default in Elasticsearch
-    systemProperty 'io.netty.allocator.numDirectArenas', '0'
 }
 
 integTestRunner {
@@ -65,9 +62,6 @@ integTestRunner {
      * other if we allow them to set the number of available processors as it's set-once in Netty.
      */
     systemProperty 'es.set.netty.runtime.available.processors', 'false'
-
-    // Disable direct buffer pooling as it is disabled by default in Elasticsearch
-    systemProperty 'io.netty.allocator.numDirectArenas', '0'
 }
 
 TaskProvider<Test> pooledTest = tasks.register("pooledTest", Test) {

test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java

@@ -243,9 +243,6 @@ public abstract class ESTestCase extends LuceneTestCase {
 
         // Enable Netty leak detection and monitor logger for logged leak errors
         System.setProperty("io.netty.leakDetection.level", "paranoid");
-
-        // Disable direct buffer pooling
-        System.setProperty("io.netty.allocator.numDirectArenas", "0");
     }
 
     protected final Logger logger = LogManager.getLogger(getClass());