| /* |
| * Copyright (c) 2015, 2016, 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. |
| * |
| * 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 org.graalvm.compiler.debug; |
| |
| import java.lang.management.ThreadMXBean; |
| |
| /** |
| * A consistent source of timing data that should be used by all facilities in the debug package. |
| */ |
| public class TimeSource { |
| private static final boolean USING_BEAN; |
| private static final ThreadMXBean threadMXBean; |
| |
| static { |
| threadMXBean = Management.getThreadMXBean(); |
| if (threadMXBean.isThreadCpuTimeSupported()) { |
| USING_BEAN = true; |
| } else { |
| USING_BEAN = false; |
| } |
| } |
| |
| /** |
| * Gets the current time of this thread in nanoseconds from the most accurate timer available on |
| * the system. The returned value will be the current time in nanoseconds precision but not |
| * necessarily nanoseconds accuracy. |
| * <p> |
| * The intended use case of this method is to measure the time a certain action takes by making |
| * successive calls to it. It should not be used to measure total times in the sense of a time |
| * stamp. |
| * |
| * @return the current thread's time in nanoseconds |
| */ |
| public static long getTimeNS() { |
| return USING_BEAN ? threadMXBean.getCurrentThreadCpuTime() : System.nanoTime(); |
| } |
| |
| } |