diff --git a/gradle/testing/defaults-tests.gradle b/gradle/testing/defaults-tests.gradle
index c74b5fc85c93..25a2291bc182 100644
--- a/gradle/testing/defaults-tests.gradle
+++ b/gradle/testing/defaults-tests.gradle
@@ -51,7 +51,7 @@ allprojects {
            includeInReproLine: false
           ],
           [propName: 'tests.jvmargs',
-           value: { -> propertyOrEnvOrDefault("tests.jvmargs", "TEST_JVM_ARGS", isCIBuild ? "" : "-XX:TieredStopAtLevel=1 -XX:+UseParallelGC -XX:ActiveProcessorCount=1") },
+           value: { -> envOrDefault("TEST_JVM_ARGS", (isCIBuild || testsDefaultVectorizationRequested()) ? "" : "-XX:TieredStopAtLevel=1 -XX:+UseParallelGC -XX:ActiveProcessorCount=1") },
            description: "Arguments passed to each forked JVM."],
           // Other settings.
           [propName: 'tests.neverUpToDate', value: true,
@@ -66,6 +66,8 @@ allprojects {
         }
         return propertyOrDefault(option.propName, option.value)
       }
+      
+      testsDefaultVectorizationRequested = { -> Boolean.parseBoolean(resolvedTestOption('tests.defaultvectorization') as String) }
 
       testsCwd = file("${buildDir}/tmp/tests-cwd")
       testsTmpDir = file(resolvedTestOption("tests.workDir"))
@@ -116,8 +118,6 @@ allprojects {
 
       ignoreFailures = resolvedTestOption("tests.haltonfailure").toBoolean() == false
 
-      jvmArgs Commandline.translateCommandline(resolvedTestOption("tests.jvmargs"))
-      
       // Up to JDK-15 we have to enforce --illegal-access=deny, because we want no code to access
       // JDK internals; JDK-16 and later will default to deny, see https://openjdk.java.net/jeps/396:
       if (rootProject.runtimeJavaVersion < JavaVersion.VERSION_16) {
diff --git a/gradle/testing/randomization.gradle b/gradle/testing/randomization.gradle
index bda6dfd299ba..9380b427cb74 100644
--- a/gradle/testing/randomization.gradle
+++ b/gradle/testing/randomization.gradle
@@ -63,6 +63,7 @@ allprojects {
 allprojects {
   plugins.withType(JavaPlugin) {
     ext {
+      String randomVectorSize = RandomPicks.randomFrom(new Random(projectSeedLong), ["default", "128", "256", "512"])
       testOptions += [
           // seed, repetition and amplification.
           [propName: 'tests.seed', value: { -> rootSeed }, description: "Sets the master randomization seed."],
@@ -107,11 +108,13 @@ allprojects {
           [propName: 'tests.bwcdir', value: null, description: "Data for backward-compatibility indexes."],
           // vectorization related
           [propName: 'tests.vectorsize',
-             value: { ->
-               RandomPicks.randomFrom(new Random(projectSeedLong), ["128", "256", "512"])
-             },
-             description: "Sets preferred vector size in bits."],
-          [propName: 'tests.forceintegervectors', value: "true", description: "Forces use of integer vectors even when slow."],
+           value: { -> testsDefaultVectorizationRequested() ? 'default' : randomVectorSize },
+           description: "Sets preferred vector size in bits."],
+          [propName: 'tests.forceintegervectors',
+            value: { -> testsDefaultVectorizationRequested() ? false : (randomVectorSize != 'default') },
+            description: "Forces use of integer vectors even when slow."],
+          [propName: 'tests.defaultvectorization', value: false,
+            description: "Uses defaults for running tests with correct JVM settings to test Panama vectorization (tests.jvmargs, tests.vectorsize, tests.forceintegervectors)."],
       ]
     }
   }
@@ -161,6 +164,8 @@ allprojects {
         // and not the test JVM itself.
         systemProperties testOptionsResolved
 
+        jvmArgs Commandline.translateCommandline(testOptionsResolved['tests.jvmargs'])
+      
         if (Boolean.parseBoolean(testOptionsResolved['tests.asserts'])) {
           jvmArgs("-ea", "-esa")
         } else {
diff --git a/lucene/core/src/java/org/apache/lucene/internal/vectorization/VectorizationProvider.java b/lucene/core/src/java/org/apache/lucene/internal/vectorization/VectorizationProvider.java
index a1f07c6a0435..32ee2aa97b3e 100644
--- a/lucene/core/src/java/org/apache/lucene/internal/vectorization/VectorizationProvider.java
+++ b/lucene/core/src/java/org/apache/lucene/internal/vectorization/VectorizationProvider.java
@@ -49,7 +49,7 @@ public abstract class VectorizationProvider {
     try {
       vs =
           Stream.ofNullable(System.getProperty("tests.vectorsize"))
-              .filter(Predicate.not(String::isEmpty))
+              .filter(Predicate.not(Set.of("", "default")::contains))
               .mapToInt(Integer::parseInt)
               .findAny();
     } catch (