Index: src/test/java/de/siegmar/logbackgelf/GelfEncoderTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/test/java/de/siegmar/logbackgelf/GelfEncoderTest.java b/src/test/java/de/siegmar/logbackgelf/GelfEncoderTest.java
--- a/src/test/java/de/siegmar/logbackgelf/GelfEncoderTest.java	(revision c4465cd35b5f2a15a91b331a61708488f2f5e916)
+++ b/src/test/java/de/siegmar/logbackgelf/GelfEncoderTest.java	(date 1724439478645)
@@ -490,4 +490,131 @@
         assertThat(encoder.getShortMessageLayout()).isNotNull();
     }
 
+    @Test
+    void millionEncodeLoop() {
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            assertThatJson(encodeToStr(simpleLoggingEvent(logger, null)))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
+    @Test
+    void millionEncodeLoopNumbersAsString() {
+        encoder.setNumbersAsString(true);
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            assertThatJson(encodeToStr(simpleLoggingEvent(logger, null)))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes with numbersAsString=true: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
+    @Test
+    void millionEncodeLoop5Fields() {
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            final var event = simpleLoggingEvent(logger, null);
+            event.addKeyValuePair(new KeyValuePair("field1","value1"));
+            event.addKeyValuePair(new KeyValuePair("field2","value2"));
+            event.addKeyValuePair(new KeyValuePair("field3","value3"));
+            event.addKeyValuePair(new KeyValuePair("field4","value4"));
+            event.addKeyValuePair(new KeyValuePair("field5","value5"));
+            assertThatJson(encodeToStr(event))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes with 5 key-value pairs: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
+    @Test
+    void millionEncodeLoop5FieldsNumbersAsString() {
+        encoder.setNumbersAsString(true);
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            final var event = simpleLoggingEvent(logger, null);
+            event.addKeyValuePair(new KeyValuePair("field1","value1"));
+            event.addKeyValuePair(new KeyValuePair("field2","value2"));
+            event.addKeyValuePair(new KeyValuePair("field3","value3"));
+            event.addKeyValuePair(new KeyValuePair("field4","value4"));
+            event.addKeyValuePair(new KeyValuePair("field5","value5"));
+            assertThatJson(encodeToStr(event))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes with 5 key-value pairs and numbersAsString=true: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
+    @Test
+    void millionEncodeLoop10Fields() {
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            final var event = simpleLoggingEvent(logger, null);
+            event.addKeyValuePair(new KeyValuePair("field1","value1"));
+            event.addKeyValuePair(new KeyValuePair("field2","value2"));
+            event.addKeyValuePair(new KeyValuePair("field3","value3"));
+            event.addKeyValuePair(new KeyValuePair("field4","value4"));
+            event.addKeyValuePair(new KeyValuePair("field5","value5"));
+            event.addKeyValuePair(new KeyValuePair("field6","value6"));
+            event.addKeyValuePair(new KeyValuePair("field7","value7"));
+            event.addKeyValuePair(new KeyValuePair("field8","value8"));
+            event.addKeyValuePair(new KeyValuePair("field9","value9"));
+            event.addKeyValuePair(new KeyValuePair("field10","value10"));
+            assertThatJson(encodeToStr(event))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes with 10 key-value pairs: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
+    @Test
+    void millionEncodeLoop10FieldsNumbersAsString() {
+        encoder.setNumbersAsString(true);
+        encoder.start();
+
+        final LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
+        final Logger logger = lc.getLogger(LOGGER_NAME);
+
+        long startTime = System.nanoTime();
+        for (int i = 0; i < 1_000_000; i++) {
+            final var event = simpleLoggingEvent(logger, null);
+            event.addKeyValuePair(new KeyValuePair("field1","value1"));
+            event.addKeyValuePair(new KeyValuePair("field2","value2"));
+            event.addKeyValuePair(new KeyValuePair("field3","value3"));
+            event.addKeyValuePair(new KeyValuePair("field4","value4"));
+            event.addKeyValuePair(new KeyValuePair("field5","value5"));
+            event.addKeyValuePair(new KeyValuePair("field6","value6"));
+            event.addKeyValuePair(new KeyValuePair("field7","value7"));
+            event.addKeyValuePair(new KeyValuePair("field8","value8"));
+            event.addKeyValuePair(new KeyValuePair("field9","value9"));
+            event.addKeyValuePair(new KeyValuePair("field10","value10"));
+            assertThatJson(encodeToStr(event))
+                    .node("full_message").isEqualTo("message 1\\n");
+        }
+        System.out.printf("Time for 1M encodes with 10 key-value pairs and numbersAsString=true: %,d ns.\n", System.nanoTime() - startTime);
+    }
+
 }