fix MachineDependentHeapTests (elastic#129699)

Author: jan-elastic

distribution/tools/server-cli/src/test/java/org/elasticsearch/server/cli/MachineDependentHeapTests.java

@@ -10,6 +10,7 @@
 package org.elasticsearch.server.cli;
 
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.util.FeatureFlag;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.ESTestCase.WithoutSecurityManager;
 import org.hamcrest.Matcher;
@@ -57,7 +58,8 @@ public void testMasterOnlyOptions() throws Exception {
         assertHeapOptions(64, containsInAnyOrder("-Xmx31744m", "-Xms31744m"), "master");
     }
 
-    public void testMlOnlyOptions() throws Exception {
+    public void testMlOnlyOptions_new() throws Exception {
+        assumeTrue("feature flag must be enabled for new memory computation", new FeatureFlag("new_ml_memory_computation").isEnabled());
         assertHeapOptions(1, containsInAnyOrder("-Xmx272m", "-Xms272m"), "ml");
         assertHeapOptions(4, containsInAnyOrder("-Xmx1092m", "-Xms1092m"), "ml");
         assertHeapOptions(32, containsInAnyOrder("-Xmx5460m", "-Xms5460m"), "ml");
@@ -67,6 +69,20 @@ public void testMlOnlyOptions() throws Exception {
         assertHeapOptions(263, containsInAnyOrder("-Xmx21228m", "-Xms21228m"), "ml");
     }
 
+    public void testMlOnlyOptions_old() throws Exception {
+        assumeTrue(
+            "feature flag must be disabled for old memory computation",
+            new FeatureFlag("new_ml_memory_computation").isEnabled() == false
+        );
+        assertHeapOptions(1, containsInAnyOrder("-Xmx408m", "-Xms408m"), "ml");
+        assertHeapOptions(4, containsInAnyOrder("-Xmx1636m", "-Xms1636m"), "ml");
+        assertHeapOptions(32, containsInAnyOrder("-Xmx8192m", "-Xms8192m"), "ml");
+        assertHeapOptions(64, containsInAnyOrder("-Xmx11468m", "-Xms11468m"), "ml");
+        // We'd never see a node this big in Cloud, but this assertion proves that the 31GB absolute maximum
+        // eventually kicks in (because 0.4 * 16 + 0.1 * (263 - 16) > 31)
+        assertHeapOptions(263, containsInAnyOrder("-Xmx31744m", "-Xms31744m"), "ml");
+    }
+
     public void testDataNodeOptions() throws Exception {
         assertHeapOptions(1, containsInAnyOrder("-Xmx512m", "-Xms512m"), "data");
         assertHeapOptions(8, containsInAnyOrder("-Xmx4096m", "-Xms4096m"), "data");