Improve performance test. Measure FPS and average processing/renderin… (#424)

* Improve performance test. Measure FPS and average processing/rendering time.
Fix #423

Author: johanvos

rta/src/test/java/com/gluonhq/richtextarea/PerformanceTests.java

@@ -19,6 +19,7 @@
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
 import javafx.application.Platform;
 import javafx.scene.Scene;
 import javafx.scene.input.KeyCode;
@@ -39,10 +40,31 @@ public static void main(String[] args) throws InterruptedException {
         pt.insertMany();
     }
 
+    /**
+     * This test measures performance of the combination {add character; render UI}
+     * It is important to measure the combination, as a performance enhancements in
+     * one part could lead to a degradation in the other part.
+     * In this test, after a warmup of 1000 characters, we add 1000 characters (to the
+     * already existing 1000 ones). After a character is added, a Pulse is requested.
+     * Ideally, we render at 60 FPS and a character insert takes much less than 16ms,
+     * so that not every requestPulse results in a separate pulse.
+     * We use a prelayoutListener to keep track of how many pulses are executed, and use
+     * that to calculate the FPS.
+     * We also calculate the average time that it takes to add and render a character. This
+     * number needs to be interpreted with caution, as it strongly depends on the performance of the
+     * individual parts, and on the number of additions that can be done within 16ms.
+     *
+     * Note that currently lots of Nodes are created in both parts, and GC activity is expected,
+     * which can influence the measured values.
+     *
+     * Run this test before and after a PR, to check for regression.
+     * @throws InterruptedException
+     */
     public void insertMany() throws InterruptedException {
-
-        final int WARMUP_CNT = 100; // how many chars to warmup
-        final int TEST_CNT = 100; // how many chars to test
+        AtomicInteger pulseCounter = new AtomicInteger(0);
+        Runnable prelayout = () -> pulseCounter.incrementAndGet();
+        final int WARMUP_CNT = 1000; // how many chars to warmup
+        final int TEST_CNT = 1000; // how many chars to test
         final int SLEEP_MS = 5000; // sleep between warmup and test
         CountDownLatch cdl = new CountDownLatch(1);
         Platform.startup(() -> {
@@ -63,7 +85,6 @@ public void insertMany() throws InterruptedException {
         ThreadLocalRandom tlr = ThreadLocalRandom.current();
         System.err.println("Will test inserts of " + TEST_CNT + " after warmup of " + WARMUP_CNT + " chars, and sleep of " + SLEEP_MS + " ms.");
 
-        long mem0 = getUsedMemory();
         long startTime = System.nanoTime();
         for (int i = 0; i < WARMUP_CNT; i++) {
             char c = (char) ('a' + tlr.nextInt(26));
@@ -72,7 +93,17 @@ public void insertMany() throws InterruptedException {
             }
             String k = String.valueOf(c);
             KeyEvent evt = new KeyEvent(KeyEvent.KEY_TYPED, k, "", KeyCode.UNDEFINED, false, false, false, false);
-            Platform.runLater(() -> skin.keyTypedListener(evt));
+            CountDownLatch testRun = new CountDownLatch(1);
+            Platform.runLater(() -> {
+                skin.keyTypedListener(evt);
+                Platform.requestNextPulse();
+                testRun.countDown();
+            });
+            boolean await = testRun.await(1, TimeUnit.SECONDS);
+            if (!await) {
+                System.err.println("ERROR warming up");
+                System.exit(1);
+            }
         }
         CountDownLatch cdl3 = new CountDownLatch(1);
         Platform.runLater(() -> cdl3.countDown());
@@ -82,6 +113,9 @@ public void insertMany() throws InterruptedException {
         System.err.println("warmup: total time = " + dur + ", average = " + (dur / (1e6 * WARMUP_CNT)) + ", now sleep for " + SLEEP_MS);
         Thread.sleep(SLEEP_MS);
         System.err.println("resume");
+        pulseCounter.set(0);
+        Platform.runLater(() -> rta.getScene().addPreLayoutPulseListener(prelayout));
+
         startTime = System.nanoTime();
         final int cnt = TEST_CNT;
         for (int i = 0; i < cnt; i++) {
@@ -91,28 +125,26 @@ public void insertMany() throws InterruptedException {
             }
             String k = String.valueOf(c);
             KeyEvent evt = new KeyEvent(KeyEvent.KEY_TYPED, k, "", KeyCode.UNDEFINED, false, false, false, false);
-            Platform.runLater(() -> skin.keyTypedListener(evt));
+            CountDownLatch prodRun = new CountDownLatch(1);
+            Platform.runLater(() -> {
+                skin.keyTypedListener(evt);
+                Platform.requestNextPulse();
+                prodRun.countDown();
+            });
+            boolean await = prodRun.await(1, TimeUnit.SECONDS);
+            if (!await) {
+                System.err.println("ERROR running test");
+                System.exit(1);
+            }
         }
         CountDownLatch cdl4 = new CountDownLatch(1);
         Platform.runLater(() -> cdl4.countDown());
         cdl4.await(10, TimeUnit.SECONDS);
         endTime = System.nanoTime();
         dur = endTime - startTime;
-        long mem1 = getUsedMemory();
-        System.err.println("total time = " + dur + ", average = " + (dur / (1e6 * cnt)) + " and used mem = " + (mem1 - mem0));
+        System.err.println("RefreshRate = "+1.e9*pulseCounter.get()/dur +" FPS");
+        System.err.println("Average duration of a character addition = " + (dur / (1e6 * cnt))+"ms");
         Platform.exit();
     }
 
-    long getUsedMemory() {
-        System.gc();
-        try {
-            Thread.sleep(50);
-        } catch (InterruptedException ex) {
-            System.getLogger(PerformanceTests.class.getName()).log(System.Logger.Level.ERROR, (String) null, ex);
-        }
-        Runtime runtime = Runtime.getRuntime();
-        long val = runtime.totalMemory() - runtime.freeMemory();
-        return val;
-    }
-
 }