1 /*
2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.jfr.api.recording.event;
27
28 import java.io.IOException;
29 import java.time.Duration;
30 import java.util.ArrayList;
31 import java.util.List;
32
33 import jdk.jfr.Recording;
34 import jdk.jfr.consumer.RecordedEvent;
35 import jdk.jfr.consumer.RecordedThread;
36 import jdk.test.lib.Asserts;
37 import jdk.test.lib.jfr.EventNames;
38 import jdk.test.lib.jfr.Events;
39
40 /*
41 * @test
42 * @summary Test event period.
43 * @key jfr
44 * @library /test/lib
45 * @run main/othervm jdk.jfr.api.recording.event.TestPeriod
46 */
47 public class TestPeriod {
48 private static final String EVENT_PATH = EventNames.ThreadAllocationStatistics;
49 private static final long ERROR_MARGIN = 20; // 186 ms has been measured, when period was set to 200 ms
50
51 public static void main(String[] args) throws Throwable {
52 long[] periods = { 100, 200 };
53 int eventCount = 4;
54 int deltaCount;
55 for (long period : periods) {
56 List<Long> deltaBetweenEvents;
57 do {
58 deltaBetweenEvents = createPeriodicEvents(period, eventCount);
59 deltaCount = deltaBetweenEvents.size();
60 if (deltaCount < eventCount - 1) {
61 System.out.println("Didn't get sufficent number of events. Retrying...");
62 System.out.println();
63 }
64 } while (deltaCount < eventCount - 1);
65 for (int i = 0; i < eventCount - 1; i++) {
66 verifyDelta(deltaBetweenEvents.get(i), period);
67 }
68 System.out.println();
69 }
70 }
71
72 private static List<Long> createPeriodicEvents(long period, int eventCount) throws Exception, IOException {
73 System.out.println("Provoking events with period " + period + " ms");
74 Recording r = new Recording();
75 r.start();
76 runWithPeriod(r, period, eventCount + 1);
77 r.stop();
78
79 long prevTime = -1;
80 List<Long> deltas = new ArrayList<>();
81 for (RecordedEvent event : Events.fromRecording(r)) {
82 if (Events.isEventType(event, EVENT_PATH) && isMyThread(event)) {
83 long timeMillis = event.getEndTime().toEpochMilli();
84 if (prevTime != -1) {
85 long delta = timeMillis - prevTime;
86 deltas.add(delta);
87 System.out.printf("event: time=%d, delta=%d%n", timeMillis, delta);
88 }
89 prevTime = timeMillis;
90 }
91 }
92 r.close();
93 return deltas;
94 }
95
96 // We only check that time is at least as expected.
97 // We ignore if time is much longer than expected, since anything can happen
98 // during heavy load,
99 private static void verifyDelta(long actual, long expected) {
100 System.out.printf("verifyDelta: actaul=%d, expected=%d (errorMargin=%d)%n", actual, expected, ERROR_MARGIN);
101 Asserts.assertGreaterThan(actual, expected - ERROR_MARGIN, "period delta too short");
102 }
103
104 private static boolean isMyThread(RecordedEvent event) {
105 Object o = event.getValue("thread");
106 if (o instanceof RecordedThread) {
107 RecordedThread rt = (RecordedThread) o;
108 return Thread.currentThread().getId() == rt.getJavaThreadId();
109 }
110 return false;
111 }
112
113 @SuppressWarnings("unused")
114 private static byte[] dummy = null;
115
116 // Generate at least minEvents event with given period
117 private static void runWithPeriod(Recording r, long period, int minEventCount) throws Exception {
118 r.enable(EVENT_PATH).withPeriod(Duration.ofMillis(period));
119 long endTime = System.currentTimeMillis() + period * minEventCount;
120 while (System.currentTimeMillis() < endTime) {
121 dummy = new byte[100];
122 Thread.sleep(1);
123 }
124 }
125
126 }