diff --git a/core/src/main/java/hudson/ClassicPluginStrategy.java b/core/src/main/java/hudson/ClassicPluginStrategy.java
index 12c3d7012a..907b2ee9c3 100644
--- a/core/src/main/java/hudson/ClassicPluginStrategy.java
+++ b/core/src/main/java/hudson/ClassicPluginStrategy.java
@@ -38,6 +38,7 @@ import jenkins.plugins.DetachedPluginsUtil;
 import jenkins.util.AntClassLoader;
 import jenkins.util.AntWithFindResourceClassLoader;
 import jenkins.util.SystemProperties;
+import jenkins.util.java.ClassNotFoundNoStackTraceException;
 import org.apache.commons.io.output.NullOutputStream;
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.Project;
@@ -55,6 +56,9 @@ import org.apache.tools.zip.ZipOutputStream;
 import org.jenkinsci.bytecode.Transformer;
 
 import edu.umd.cs.findbugs.annotations.NonNull;
+import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.Beta;
+
 import java.io.Closeable;
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -92,6 +96,7 @@ public class ClassicPluginStrategy implements PluginStrategy {
     };
 
     private PluginManager pluginManager;
+    private boolean fillInStackTracesOnClassNotFoundException;
 
     /**
      * All the plugins eventually delegate this classloader to load core, servlet APIs, and SE runtime.
@@ -102,6 +107,19 @@ public class ClassicPluginStrategy implements PluginStrategy {
         this.pluginManager = pluginManager;
     }
 
+    /**
+     * Sets whether the classloader should include stacktraces on {@link ClassNotFoundException}s.
+     *
+     * @param fillInStackTraces {@code true} to fill in stacktraces.
+     *        The classloader does not inject stacktraces by default.
+     * @since TODO
+     */
+    @Restricted(Beta.class)
+    public ClassicPluginStrategy withFillInStackTracesOnClassNotFoundException(boolean fillInStackTraces) {
+        this.fillInStackTracesOnClassNotFoundException = fillInStackTraces;
+        return this;
+    }
+
     @Override public String getShortName(File archive) throws IOException {
         Manifest manifest;
         if (!archive.exists()) {
@@ -296,11 +314,13 @@ public class ClassicPluginStrategy implements PluginStrategy {
                 classLoader.setParentFirst( false );
                 classLoader.setParent( parent );
                 classLoader.addPathFiles( paths );
+                classLoader.withFillInStackTracesOnClassNotFound(fillInStackTracesOnClassNotFoundException);
                 return classLoader;
             }
         }
 
         AntClassLoader2 classLoader = new AntClassLoader2(parent);
+        classLoader.withFillInStackTracesOnClassNotFound(fillInStackTracesOnClassNotFoundException);
         classLoader.addPathFiles(paths);
         return classLoader;
     }
@@ -649,7 +669,8 @@ public class ClassicPluginStrategy implements PluginStrategy {
                 }
             }
 
-            throw new ClassNotFoundException(name);
+            throw fillInStackTracesOnClassNotFoundException ?
+                    new ClassNotFoundException(name) : new ClassNotFoundNoStackTraceException(name);
         }
 
         @Override
diff --git a/core/src/main/java/hudson/PluginManager.java b/core/src/main/java/hudson/PluginManager.java
index 1507548052..323692b18e 100644
--- a/core/src/main/java/hudson/PluginManager.java
+++ b/core/src/main/java/hudson/PluginManager.java
@@ -1213,8 +1213,13 @@ public abstract class PluginManager extends AbstractModelObject implements OnMas
 			LOGGER.info("Falling back to ClassicPluginStrategy");
 		}
 
-		// default and fallback
-		return new ClassicPluginStrategy(this);
+		// Default and fallback strategy
+        // The default Plugin Manager implementation does not propagate/log stacktraces for ClassNotFoundExceptions,
+        // hence stacktraces are omitted by default for better performance.
+        boolean fillInClassNotFoundExceptionStackTraces =SystemProperties.getBoolean(
+                ClassicPluginStrategy.class.getName() + ".fillInClassNotFoundExceptionStackTraces", false);
+		return new ClassicPluginStrategy(this)
+                .withFillInStackTracesOnClassNotFoundException(fillInClassNotFoundExceptionStackTraces);
     }
 
     public PluginStrategy getPluginStrategy() {
diff --git a/core/src/main/java/jenkins/util/AntClassLoader.java b/core/src/main/java/jenkins/util/AntClassLoader.java
index 7843abb69a..f14269d391 100644
--- a/core/src/main/java/jenkins/util/AntClassLoader.java
+++ b/core/src/main/java/jenkins/util/AntClassLoader.java
@@ -18,6 +18,7 @@
 package jenkins.util;
 
 import jenkins.telemetry.impl.java11.MissingClassTelemetry;
+import jenkins.util.java.ClassNotFoundNoStackTraceException;
 import org.apache.tools.ant.BuildEvent;
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.Project;
@@ -30,6 +31,7 @@ import org.apache.tools.ant.util.JavaEnvUtils;
 import org.apache.tools.ant.util.LoaderUtils;
 import org.apache.tools.ant.util.ReflectUtil;
 import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.Beta;
 import org.kohsuke.accmod.restrictions.NoExternalUse;
 
 import edu.umd.cs.findbugs.annotations.CheckForNull;
@@ -241,6 +243,12 @@ public class AntClassLoader extends ClassLoader implements SubBuildListener {
      */
     private boolean isContextLoaderSaved = false;
 
+    /**
+     * Whether or not to include stacktraces in {@link ClassNotFoundException}.
+     * @since TODO
+     */
+    private boolean fillInStackTracesOnClassNotFoundException;
+
     /**
      * Create an Ant ClassLoader for a given project, with
      * a parent classloader and an initial classpath.
@@ -568,6 +576,19 @@ public class AntClassLoader extends ClassLoader implements SubBuildListener {
         ignoreBase = isolated;
     }
 
+    /**
+     * Sets whether the classloader should include stacktraces on {@link ClassNotFoundException}s.
+     *
+     * @param fillInStackTraces {@code true} to fill in stacktraces.
+     *        The classloader does not add stacktraces by default.
+     * @since TODO
+     */
+    @Restricted(Beta.class)
+    public AntClassLoader withFillInStackTracesOnClassNotFound(boolean fillInStackTraces) {
+        this.fillInStackTracesOnClassNotFoundException = fillInStackTraces;
+        return this;
+    }
+
     /**
      * Forces initialization of a class in a JDK 1.1 compatible, albeit hacky
      * way.
@@ -1384,7 +1405,9 @@ public class AntClassLoader extends ClassLoader implements SubBuildListener {
                         + ioe.getMessage() + ")", Project.MSG_VERBOSE);
             }
         }
-        throw new ClassNotFoundException(name);
+
+        throw fillInStackTracesOnClassNotFoundException
+                ? new ClassNotFoundException(name) : new ClassNotFoundNoStackTraceException(name);
     }
 
     /**
diff --git a/core/src/main/java/jenkins/util/java/ClassNotFoundNoStackTraceException.java b/core/src/main/java/jenkins/util/java/ClassNotFoundNoStackTraceException.java
new file mode 100644
index 0000000000..34ade95ad8
--- /dev/null
+++ b/core/src/main/java/jenkins/util/java/ClassNotFoundNoStackTraceException.java
@@ -0,0 +1,43 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2020 CloudBees, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package jenkins.util.java;
+
+import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.NoExternalUse;
+
+/**
+ * {@link ClassNotFoundException} which does not store the stacktrace on initialization.
+ * It improves classloading performance when the stacktrace is ignored,
+ * e.g. like in {@link hudson.ClassicPluginStrategy}.
+ */
+@Restricted(NoExternalUse.class)
+public class ClassNotFoundNoStackTraceException extends ClassNotFoundException {
+    public ClassNotFoundNoStackTraceException(String className) {
+        super(className);
+    }
+
+    public Throwable fillInStackTrace() {
+        return this;
+    }
+}