diff --git a/README.md b/README.md
index a698cd0..8c0a5a6 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# ja-netfilter v2.0.0
+# ja-netfilter v2.0.1
 
 ### A javaagent framework
 
diff --git a/pom.xml b/pom.xml
index 612102e..5164110 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>com.ja-netfilter</groupId>
     <artifactId>ja-netfilter</artifactId>
-    <version>2.0.0</version>
+    <version>2.0.1</version>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
diff --git a/src/main/java/com/janetfilter/core/Dispatcher.java b/src/main/java/com/janetfilter/core/Dispatcher.java
index b269516..167f49d 100644
--- a/src/main/java/com/janetfilter/core/Dispatcher.java
+++ b/src/main/java/com/janetfilter/core/Dispatcher.java
@@ -60,7 +60,7 @@ public final class Dispatcher implements ClassFileTransformer {
                     classFileBuffer = transformer.transform(className, classFileBuffer, order++);
                 }
             } catch (Throwable e) {
-                DebugInfo.output("Transform class failed: " + e.getMessage());
+                DebugInfo.output("Transform class failed: " + className, e);
             }
         } while (false);
 
diff --git a/src/main/java/com/janetfilter/core/Initializer.java b/src/main/java/com/janetfilter/core/Initializer.java
index 9d887d6..e827a5c 100644
--- a/src/main/java/com/janetfilter/core/Initializer.java
+++ b/src/main/java/com/janetfilter/core/Initializer.java
@@ -23,7 +23,7 @@ public class Initializer {
             try {
                 inst.retransformClasses(c);
             } catch (Throwable e) {
-                DebugInfo.output("Retransform class failed: " + name);
+                DebugInfo.output("Retransform class failed: " + name, e);
             }
         }
     }
diff --git a/src/main/java/com/janetfilter/core/Launcher.java b/src/main/java/com/janetfilter/core/Launcher.java
index dfa71fc..724dad2 100644
--- a/src/main/java/com/janetfilter/core/Launcher.java
+++ b/src/main/java/com/janetfilter/core/Launcher.java
@@ -9,7 +9,7 @@ import java.net.URL;
 import java.util.jar.JarFile;
 
 public class Launcher {
-    private static final String VERSION = "v2.0.0";
+    private static final String VERSION = "v2.0.1";
 
     public static void main(String[] args) {
         printUsage();
@@ -22,7 +22,7 @@ public class Launcher {
         try {
             jarURI = getJarURI();
         } catch (Throwable e) {
-            DebugInfo.output("ERROR: Can not locate ja-netfilter jar file.");
+            DebugInfo.output("ERROR: Can not locate ja-netfilter jar file.", e);
             return;
         }
 
@@ -30,7 +30,7 @@ public class Launcher {
         try {
             inst.appendToBootstrapClassLoaderSearch(new JarFile(agentFile));
         } catch (Throwable e) {
-            DebugInfo.output("ERROR: Can not access ja-netfilter jar file.");
+            DebugInfo.output("ERROR: Can not access ja-netfilter jar file.", e);
             return;
         }
 
diff --git a/src/main/java/com/janetfilter/core/commons/DebugInfo.java b/src/main/java/com/janetfilter/core/commons/DebugInfo.java
index d93a1cd..0f54b5d 100644
--- a/src/main/java/com/janetfilter/core/commons/DebugInfo.java
+++ b/src/main/java/com/janetfilter/core/commons/DebugInfo.java
@@ -5,7 +5,11 @@ import com.janetfilter.core.utils.DateUtils;
 public class DebugInfo {
     private static final boolean DEBUG = "1".equals(System.getenv("JANF_DEBUG")) || "1".equals(System.getProperty("janf.debug"));
 
-    public static void output(String content) { // No logger lib required
+    public static void output(String content) {
+        output(content, null);
+    }
+
+    public static void output(String content, Throwable e) { // No logger lib required
         if (!DEBUG) {
             return;
         }
@@ -15,7 +19,15 @@ public class DebugInfo {
         StackTraceElement[] traces = new Throwable().getStackTrace();
         String caller = traces.length < 2 ? "UNKNOWN" : traces[1].toString();
 
-        System.out.printf(template, DateUtils.formatNow(), caller, content);
-        System.out.flush();
+        String outContent = String.format(template, DateUtils.formatNow(), caller, content);
+        if (null == e) {
+            System.out.print(outContent);
+            return;
+        }
+
+        synchronized (DebugInfo.class) {
+            System.out.print(outContent);
+            e.printStackTrace(System.err);
+        }
     }
 }
diff --git a/src/main/java/com/janetfilter/core/plugin/PluginManager.java b/src/main/java/com/janetfilter/core/plugin/PluginManager.java
index 803edef..264637e 100644
--- a/src/main/java/com/janetfilter/core/plugin/PluginManager.java
+++ b/src/main/java/com/janetfilter/core/plugin/PluginManager.java
@@ -29,6 +29,8 @@ public final class PluginManager {
     }
 
     public void loadPlugins() {
+        long startTime = System.currentTimeMillis();
+
         File pluginsDirectory = environment.getPluginsDir();
         if (!pluginsDirectory.exists() || !pluginsDirectory.isDirectory()) {
             return;
@@ -50,9 +52,9 @@ public final class PluginManager {
                 throw new RuntimeException("Load plugin timeout");
             }
 
-            DebugInfo.output("============ All plugins loaded ============");
+            DebugInfo.output(String.format("============ All plugins loaded, %.2fs elapsed ============", (System.currentTimeMillis() - startTime) / 1000D));
         } catch (Throwable e) {
-            DebugInfo.output("Load plugin failed: " + e.getMessage());
+            DebugInfo.output("Load plugin failed", e);
         }
     }
 
@@ -93,7 +95,7 @@ public final class PluginManager {
 
                 DebugInfo.output("Plugin loaded: {name=" + pluginEntry.getName() + ", version=" + pluginEntry.getVersion() + ", author=" + pluginEntry.getAuthor() + "}");
             } catch (Throwable e) {
-                DebugInfo.output("Parse plugin info failed: " + e.getMessage());
+                DebugInfo.output("Parse plugin info failed", e);
             }
         }
     }