Misc: clock benchmark

benchmarks/src/main/java/org/questdb/ClockBenchmark.java

+/*******************************************************************************
+ *    ___                  _   ____  ____
+ *   / _ \ _   _  ___  ___| |_|  _ \| __ )
+ *  | | | | | | |/ _ \/ __| __| | | |  _ \
+ *  | |_| | |_| |  __/\__ \ |_| |_| | |_) |
+ *   \__\_\\__,_|\___||___/\__|____/|____/
+ *
+ * Copyright (C) 2014-2019 Appsicle
+ *
+ * This program is free software: you can redistribute it and/or  modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ ******************************************************************************/
+
+package org.questdb;
+
+import com.questdb.std.Os;
+import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+import java.util.concurrent.TimeUnit;
+
+@State(Scope.Thread)
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+public class ClockBenchmark {
+
+    public static void main(String[] args) throws RunnerException {
+        Options opt = new OptionsBuilder()
+                .include(ClockBenchmark.class.getSimpleName())
+                .warmupIterations(5)
+                .measurementIterations(5)
+                .addProfiler("gc")
+                .forks(1)
+                .build();
+
+        new Runner(opt).run();
+    }
+
+    @Benchmark
+    public long testCurrentTimeMicros() {
+        return Os.currentTimeMicros();
+    }
+
+    @Benchmark
+    public long testCurrentTimeNanos() {
+        return Os.currentTimeNanos();
+    }
+
+    @Benchmark
+    public long testCurrentTimeMillis() {
+        return System.currentTimeMillis();
+    }
+
+}