Клиент: начальный импорт кодовой базы

Основа — Horizon (MIT). История апстрима не переносится: этот репозиторий ведёт свою.

tests/java/JfrFixture.java

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+import java.nio.file.Path;
+import java.time.Duration;
+import jdk.jfr.Recording;
+
+/** Produces real JDK counter/GC events for the reader's independent integration check. */
+public final class JfrFixture {
+    private static volatile Object[] retained;
+    public static void main(String[] args) throws Exception {
+        Thread.currentThread().setName("Horizon JFR fixture \"quoted\"\tthread");
+        try (var recording = new Recording()) {
+            recording.enable("jdk.ThreadAllocationStatistics").withPeriod(Duration.ofMillis(100));
+            recording.enable("jdk.ExecutionSample").withPeriod(Duration.ofMillis(10));
+            recording.enable("jdk.ObjectAllocationSample").withStackTrace();
+            recording.enable("jdk.GarbageCollection");
+            recording.enable("jdk.GCPhasePause");
+            recording.enable("jdk.GCHeapSummary");
+            recording.start();
+            for (int batch = 0; batch < 12; batch++) {
+                Object[] objects = new Object[100_000];
+                for (int i = 0; i < objects.length; i++) objects[i] = new byte[32 + (i % 8)];
+                retained = objects;
+                Thread.sleep(120);
+            }
+            System.gc();
+            Thread.sleep(250);
+            recording.stop();
+            recording.dump(Path.of(args[0]));
+        }
+    }
+}