--- /dev/null	2017-11-09 09:38:01.297999907 +0100
+++ new/test/jdk/jdk/jfr/api/event/TestShouldCommit.java	2018-04-09 16:41:30.253794529 +0200
@@ -0,0 +1,194 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.jfr.api.event;
+
+import java.time.Duration;
+
+import jdk.jfr.Event;
+import jdk.jfr.Recording;
+import jdk.test.lib.Asserts;
+
+/*
+ * @test
+ * @summary Test enable/disable event and verify recording has expected events.
+ * @key jfr
+ * @library /test/lib
+ * @run main/othervm -Xlog:jfr+event+setting=trace jdk.jfr.api.event.TestShouldCommit
+ */
+
+public class TestShouldCommit {
+
+    public static void main(String[] args) throws Exception {
+        Recording rA = new Recording();
+
+        verifyShouldCommitFalse(); // No active recordings
+
+        rA.start();
+        rA.enable(MyEvent.class).withoutThreshold(); // recA=all
+        verifyShouldCommitTrue();
+
+        setThreshold(rA, 100); // recA=100
+        verifyThreshold(100);
+
+        setThreshold(rA, 200); // recA=200
+        verifyThreshold(200);
+
+        Recording rB = new Recording();
+        verifyThreshold(200);  // recA=200, recB=not started
+
+        rB.start();
+        verifyThreshold(200);  // recA=200, recB=not specified, settings from recA is used.
+
+        setThreshold(rB, 100); // recA=200, recB=100
+        verifyThreshold(100);
+
+        setThreshold(rB, 300); // recA=200, recB=300
+        verifyThreshold(200);
+
+        rA.disable(MyEvent.class); // recA=disabled, recB=300
+
+        verifyThreshold(300);
+
+        rB.disable(MyEvent.class); // recA=disabled, recB=disabled
+        verifyShouldCommitFalse();
+
+        setThreshold(rA, 200); // recA=200, recB=disabled
+        verifyThreshold(200);
+
+        rB.enable(MyEvent.class).withoutThreshold(); // recA=200, recB=all
+        verifyShouldCommitTrue();
+
+        setThreshold(rB, 100); // recA=200, recB=100
+        verifyThreshold(100);
+
+        rB.stop(); // recA=200, recB=stopped
+        verifyThreshold(200);
+
+        rA.stop(); // recA=stopped, recB=stopped
+        verifyShouldCommitFalse();
+
+        rA.close();
+        rB.close();
+
+        verifyShouldCommitFalse();
+    }
+
+    private static void setThreshold(Recording r, long millis) {
+        r.enable(MyEvent.class).withThreshold(Duration.ofMillis(millis));
+    }
+
+    private static void verifyThreshold(long threshold) throws Exception {
+        // Create 2 events, with different sleep time between begin() and end()
+        // First event ends just before threshold, the other just after.
+        verifyThreshold(threshold-5, threshold);
+        verifyThreshold(threshold+5, threshold);
+    }
+
+    private static void verifyThreshold(long sleepMs, long thresholdMs) throws Exception {
+        MyEvent event = new MyEvent();
+
+        long beforeStartNanos = System.nanoTime();
+        event.begin();
+        long afterStartNanos = System.nanoTime();
+
+        Thread.sleep(sleepMs);
+
+        long beforeStopNanos = System.nanoTime();
+        event.end();
+        long afterStopNanos = System.nanoTime();
+
+        boolean actualShouldCommit = event.shouldCommit();
+
+        final long safetyMarginNanos = 2000000; // Allow an error of 2 ms. May have to be tuned.
+
+        //Duration of event has been at least minDurationMicros
+        long minDurationMicros = (beforeStopNanos - afterStartNanos - safetyMarginNanos) / 1000;
+        //Duration of event has been at most maxDurationMicros
+        long maxDurationMicros = (afterStopNanos - beforeStartNanos + safetyMarginNanos) / 1000;
+        Asserts.assertLessThanOrEqual(minDurationMicros, maxDurationMicros, "Wrong min/max duration. Test error.");
+
+        long thresholdMicros = thresholdMs * 1000;
+        Boolean shouldCommit = null;
+        if (minDurationMicros > thresholdMicros) {
+            shouldCommit = new Boolean(true);  // shouldCommit() must be true
+        } else if (maxDurationMicros < thresholdMicros) {
+            shouldCommit = new Boolean(false); // shouldCommit() must be false
+        } else {
+            // Too close to call. No checks are done since we are not sure of expected shouldCommit().
+        }
+
+        System.out.printf(
+            "threshold=%d, duration=[%d-%d], shouldCommit()=%b, expected=%s%n",
+            thresholdMicros, minDurationMicros, maxDurationMicros, actualShouldCommit,
+            (shouldCommit!=null ? shouldCommit : "too close to call"));
+
+        try {
+            if (shouldCommit != null) {
+                Asserts.assertEquals(shouldCommit.booleanValue(), actualShouldCommit, "Wrong shouldCommit()");
+            }
+        } catch (Exception e) {
+            System.out.println("Unexpected value of shouldCommit(). Searching for active threshold...");
+            searchThreshold(thresholdMs, 2000+thresholdMs);
+            throw e;
+        }
+    }
+
+    // Sleeps until shouldCommit() is true, or give up. Used for logging.
+    private static void searchThreshold(long expectedMs, long maxMs) throws Exception {
+        long start = System.nanoTime();
+        long stop = start + maxMs * 1000000;
+
+        MyEvent event = new MyEvent();
+        event.begin();
+        event.end();
+
+        while (!event.shouldCommit() && System.nanoTime() < stop) {
+            Thread.sleep(1);
+            event.end();
+        }
+        long durationMicros = (System.nanoTime() - start) / 1000;
+        long expectedMicros = expectedMs * 1000;
+        System.out.printf("shouldCommit()=%b after %,d ms, expected %,d%n", event.shouldCommit(), durationMicros, expectedMicros);
+    }
+
+    private static void verifyShouldCommitFalse() {
+        MyEvent event = new MyEvent();
+        event.begin();
+        event.end();
+        Asserts.assertFalse(event.shouldCommit(), "shouldCommit() expected false");
+    }
+
+    private static void verifyShouldCommitTrue() {
+        MyEvent event = new MyEvent();
+        event.begin();
+        event.end();
+        Asserts.assertTrue(event.shouldCommit(), "shouldCommit() expected true");
+    }
+
+    private static class MyEvent extends Event {
+    }
+
+}