Cleanup benchmarks and test both impl and impl-lite. (#1022)

* Cleanup benchmarks and test both impl and impl-lite.

* Fix comments.

6 files changed, 159 insertions, 157 deletions

diff --git a/benchmarks/README.md b/benchmarks/README.md
index e4027008..617333bf 100644
--- a/benchmarks/README.md
+++ b/benchmarks/README.md
@@ -3,5 +3,20 @@
 ## To run the benchmark use
 
 ```
-$ ./gradlew :benchmarks:jmh
+$ ./gradlew :opencensus-benchmarks:jmh
 ```
+
+## To debug compilation errors
+When you make incompatible changes in the Benchmarks classes you may get compilation errors which
+are related to the old code not being compatible with the new code. Some of the reasons are:
+* Any plugin cannot delete the generated code (jmh generates code) because if the user configured
+the directory as the same as source code the plugin will delete users source code.
+* After you run jmh a gradle demon will stay alive which may cache the generated code in memory and 
+generates the same code even if the files were changed.
+
+Run this commands to clean the Gradle's cache:
+```bash
+./gradlew --stop
+rm -fr .gradle/
+rm -fr benchmarks/build
+```
\ No newline at end of file
diff --git a/benchmarks/build.gradle b/benchmarks/build.gradle
index 47a59d4e..dcfda9bf 100644
--- a/benchmarks/build.gradle
+++ b/benchmarks/build.gradle
@@ -28,6 +28,7 @@ jmh {
 dependencies {
     compile project(':opencensus-api'),
             project(':opencensus-impl-core'),
+            project(':opencensus-impl-lite'),
             project(':opencensus-impl')
 }
 
diff --git a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/BenchmarksUtil.java b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/BenchmarksUtil.java
new file mode 100644
index 00000000..e917817a
--- /dev/null
+++ b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/BenchmarksUtil.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2018, OpenCensus Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.opencensus.benchmarks.trace;
+
+import io.opencensus.impllite.trace.TraceComponentImplLite;
+import io.opencensus.trace.Tracer;
+import io.opencensus.trace.Tracing;
+
+/** Util class for Benchmarks. */
+final class BenchmarksUtil {
+  private static final TraceComponentImplLite traceComponentImplLite = new TraceComponentImplLite();
+
+  static Tracer getTracer(String implementation) {
+    if (implementation.equals("impl")) {
+      // We can return the global tracer here because if impl is linked the global tracer will be
+      // the impl one.
+      // TODO(bdrutu): Make everything not be a singleton (disruptor, etc.) and use a new
+      // TraceComponentImpl similar to TraceComponentImplLite.
+      return Tracing.getTracer();
+    } else if (implementation.equals("impl-lite")) {
+      return traceComponentImplLite.getTracer();
+    } else {
+      throw new RuntimeException("Invalid tracer implementation requested.");
+    }
+  }
+
+  // Avoid instances of this class.
+  private BenchmarksUtil() {}
+}
diff --git a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsNonSampledSpanBenchmark.java b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsBenchmark.java
index ffdc802b..992937a1 100644
--- a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsNonSampledSpanBenchmark.java
+++ b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsBenchmark.java
@@ -16,84 +16,107 @@
 
 package io.opencensus.benchmarks.trace;
 
+import static com.google.common.base.Preconditions.checkState;
+
 import io.opencensus.trace.AttributeValue;
+import io.opencensus.trace.BlankSpan;
 import io.opencensus.trace.Link;
+import io.opencensus.trace.MessageEvent.Type;
 import io.opencensus.trace.Span;
 import io.opencensus.trace.Tracer;
-import io.opencensus.trace.Tracing;
 import io.opencensus.trace.samplers.Samplers;
 import java.util.concurrent.TimeUnit;
 import org.openjdk.jmh.annotations.Benchmark;
 import org.openjdk.jmh.annotations.BenchmarkMode;
 import org.openjdk.jmh.annotations.Mode;
 import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Param;
 import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
 import org.openjdk.jmh.annotations.State;
 import org.openjdk.jmh.annotations.TearDown;
 
 /** Benchmarks for {@link Span} to record trace events. */
 @State(Scope.Benchmark)
-public class RecordTraceEventsNonSampledSpanBenchmark {
-  private static final Tracer tracer = Tracing.getTracer();
+public class RecordTraceEventsBenchmark {
   private static final String SPAN_NAME = "MySpanName";
   private static final String ANNOTATION_DESCRIPTION = "MyAnnotation";
   private static final String ATTRIBUTE_KEY = "MyAttributeKey";
   private static final String ATTRIBUTE_VALUE = "MyAttributeValue";
-  private final Span linkedSpan =
-      tracer
-          .spanBuilderWithExplicitParent(SPAN_NAME, null)
-          .setSampler(Samplers.neverSample())
-          .startSpan();
-  private final Span span =
-      tracer
-          .spanBuilderWithExplicitParent(SPAN_NAME, null)
-          .setSampler(Samplers.neverSample())
-          .startSpan();
 
-  /** TearDown method. */
-  @TearDown
-  public void doTearDown() {
-    span.end();
-    linkedSpan.end();
+  @State(Scope.Benchmark)
+  public static class Data {
+
+    private Span linkedSpan = BlankSpan.INSTANCE;
+    private Span span = BlankSpan.INSTANCE;
+
+    @Param({"impl", "impl-lite"})
+    String implementation;
+
+    @Param({"true", "false"})
+    boolean sampled;
+
+    @Setup
+    public void setup() {
+      Tracer tracer = BenchmarksUtil.getTracer(implementation);
+      linkedSpan =
+          tracer
+              .spanBuilderWithExplicitParent(SPAN_NAME, null)
+              .setSampler(sampled ? Samplers.alwaysSample() : Samplers.neverSample())
+              .startSpan();
+      span =
+          tracer
+              .spanBuilderWithExplicitParent(SPAN_NAME, null)
+              .setSampler(sampled ? Samplers.alwaysSample() : Samplers.neverSample())
+              .startSpan();
+    }
+
+    @TearDown
+    public void doTearDown() {
+      checkState(linkedSpan != BlankSpan.INSTANCE, "Uninitialized linkedSpan");
+      checkState(span != BlankSpan.INSTANCE, "Uninitialized span");
+      linkedSpan.end();
+      span.end();
+    }
   }
 
   /** This benchmark attempts to measure performance of adding an attribute to the span. */
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span putAttribute() {
-    span.putAttribute(ATTRIBUTE_KEY, AttributeValue.stringAttributeValue(ATTRIBUTE_VALUE));
-    return span;
+  public Span putAttribute(Data data) {
+    data.span.putAttribute(ATTRIBUTE_KEY, AttributeValue.stringAttributeValue(ATTRIBUTE_VALUE));
+    return data.span;
   }
 
   /** This benchmark attempts to measure performance of adding an annotation to the span. */
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span addAnnotation() {
-    span.addAnnotation(ANNOTATION_DESCRIPTION);
-    return span;
+  public Span addAnnotation(Data data) {
+    data.span.addAnnotation(ANNOTATION_DESCRIPTION);
+    return data.span;
   }
 
   /** This benchmark attempts to measure performance of adding a network event to the span. */
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  @SuppressWarnings("deprecation")
-  public Span addNetworkEvent() {
-    span.addNetworkEvent(
-        io.opencensus.trace.NetworkEvent.builder(io.opencensus.trace.NetworkEvent.Type.RECV, 1)
+  public Span addMessageEvent(Data data) {
+    data.span.addMessageEvent(
+        io.opencensus.trace.MessageEvent.builder(Type.RECEIVED, 1)
             .setUncompressedMessageSize(3)
             .build());
-    return span;
+    return data.span;
   }
 
   /** This benchmark attempts to measure performance of adding a link to the span. */
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span addLink() {
-    span.addLink(Link.fromSpanContext(linkedSpan.getContext(), Link.Type.PARENT_LINKED_SPAN));
-    return span;
+  public Span addLink(Data data) {
+    data.span.addLink(
+        Link.fromSpanContext(data.linkedSpan.getContext(), Link.Type.PARENT_LINKED_SPAN));
+    return data.span;
   }
 }
diff --git a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsSampledSpanBenchmark.java b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsSampledSpanBenchmark.java
deleted file mode 100644
index 71b97316..00000000
--- a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/RecordTraceEventsSampledSpanBenchmark.java
+++ /dev/null
@@ -1,99 +0,0 @@
-/*
- * Copyright 2017, OpenCensus Authors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package io.opencensus.benchmarks.trace;
-
-import io.opencensus.trace.AttributeValue;
-import io.opencensus.trace.Link;
-import io.opencensus.trace.Span;
-import io.opencensus.trace.Tracer;
-import io.opencensus.trace.Tracing;
-import io.opencensus.trace.samplers.Samplers;
-import java.util.concurrent.TimeUnit;
-import org.openjdk.jmh.annotations.Benchmark;
-import org.openjdk.jmh.annotations.BenchmarkMode;
-import org.openjdk.jmh.annotations.Mode;
-import org.openjdk.jmh.annotations.OutputTimeUnit;
-import org.openjdk.jmh.annotations.Scope;
-import org.openjdk.jmh.annotations.State;
-import org.openjdk.jmh.annotations.TearDown;
-
-/** Benchmarks for {@link Span} to record trace events. */
-@State(Scope.Benchmark)
-public class RecordTraceEventsSampledSpanBenchmark {
-  private static final Tracer tracer = Tracing.getTracer();
-  private static final String SPAN_NAME = "MySpanName";
-  private static final String ANNOTATION_DESCRIPTION = "MyAnnotation";
-  private static final String ATTRIBUTE_KEY = "MyAttributeKey";
-  private static final String ATTRIBUTE_VALUE = "MyAttributeValue";
-  private final Span linkedSpan =
-      tracer
-          .spanBuilderWithExplicitParent(SPAN_NAME, null)
-          .setSampler(Samplers.alwaysSample())
-          .startSpan();
-  private final Span span =
-      tracer
-          .spanBuilderWithExplicitParent(SPAN_NAME, null)
-          .setSampler(Samplers.alwaysSample())
-          .startSpan();
-
-  /** TearDown method. */
-  @TearDown
-  public void doTearDown() {
-    span.end();
-    linkedSpan.end();
-  }
-
-  /** This benchmark attempts to measure performance of adding an attribute to the span. */
-  @Benchmark
-  @BenchmarkMode(Mode.SampleTime)
-  @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span putAttribute() {
-    span.putAttribute(ATTRIBUTE_KEY, AttributeValue.stringAttributeValue(ATTRIBUTE_VALUE));
-    return span;
-  }
-
-  /** This benchmark attempts to measure performance of adding an annotation to the span. */
-  @Benchmark
-  @BenchmarkMode(Mode.SampleTime)
-  @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span addAnnotation() {
-    span.addAnnotation(ANNOTATION_DESCRIPTION);
-    return span;
-  }
-
-  /** This benchmark attempts to measure performance of adding a network event to the span. */
-  @Benchmark
-  @BenchmarkMode(Mode.SampleTime)
-  @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  @SuppressWarnings("deprecation")
-  public Span addNetworkEvent() {
-    span.addNetworkEvent(
-        io.opencensus.trace.NetworkEvent.builder(io.opencensus.trace.NetworkEvent.Type.RECV, 1)
-            .setUncompressedMessageSize(3)
-            .build());
-    return span;
-  }
-
-  /** This benchmark attempts to measure performance of adding a link to the span. */
-  @Benchmark
-  @BenchmarkMode(Mode.SampleTime)
-  @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span addLink() {
-    span.addLink(Link.fromSpanContext(linkedSpan.getContext(), Link.Type.PARENT_LINKED_SPAN));
-    return span;
-  }
-}
diff --git a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/StartEndSpanBenchmark.java b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/StartEndSpanBenchmark.java
index cd677228..02f77f5f 100644
--- a/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/StartEndSpanBenchmark.java
+++ b/benchmarks/src/jmh/java/io/opencensus/benchmarks/trace/StartEndSpanBenchmark.java
@@ -16,33 +16,52 @@
 
 package io.opencensus.benchmarks.trace;
 
+import static com.google.common.base.Preconditions.checkState;
+
+import io.opencensus.trace.BlankSpan;
 import io.opencensus.trace.Span;
 import io.opencensus.trace.Tracer;
-import io.opencensus.trace.Tracing;
 import io.opencensus.trace.samplers.Samplers;
 import java.util.concurrent.TimeUnit;
 import org.openjdk.jmh.annotations.Benchmark;
 import org.openjdk.jmh.annotations.BenchmarkMode;
 import org.openjdk.jmh.annotations.Mode;
 import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Param;
 import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
 import org.openjdk.jmh.annotations.State;
 import org.openjdk.jmh.annotations.TearDown;
 
 /** Benchmarks for {@link io.opencensus.trace.SpanBuilder} and {@link Span}. */
 @State(Scope.Benchmark)
 public class StartEndSpanBenchmark {
-  private static final Tracer tracer = Tracing.getTracer();
   private static final String SPAN_NAME = "MySpanName";
-  private final Span rootSpan =
-      tracer
-          .spanBuilderWithExplicitParent(SPAN_NAME, null)
-          .setSampler(Samplers.neverSample())
-          .startSpan();
 
-  @TearDown
-  public void doTearDown() {
-    rootSpan.end();
+  @State(Scope.Benchmark)
+  public static class Data {
+    private Tracer tracer;
+    private Span rootSpan = BlankSpan.INSTANCE;
+
+    @Param({"impl", "impl-lite"})
+    String implementation;
+
+    @Setup
+    public void setup() {
+      tracer = BenchmarksUtil.getTracer(implementation);
+
+      rootSpan =
+          tracer
+              .spanBuilderWithExplicitParent(SPAN_NAME, null)
+              .setSampler(Samplers.neverSample())
+              .startSpan();
+    }
+
+    @TearDown
+    public void doTearDown() {
+      checkState(rootSpan != BlankSpan.INSTANCE, "Uninitialized rootSpan");
+      rootSpan.end();
+    }
   }
 
   /**
@@ -52,9 +71,9 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndNonSampledRootSpan() {
+  public Span startEndNonSampledRootSpan(Data data) {
     Span span =
-        tracer
+        data.tracer
             .spanBuilderWithExplicitParent(SPAN_NAME, null)
             .setSampler(Samplers.neverSample())
             .startSpan();
@@ -69,9 +88,9 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndRecordEventsRootSpan() {
+  public Span startEndRecordEventsRootSpan(Data data) {
     Span span =
-        tracer
+        data.tracer
             .spanBuilderWithExplicitParent(SPAN_NAME, null)
             .setSampler(Samplers.neverSample())
             .setRecordEvents(true)
@@ -86,8 +105,8 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndSampledRootSpan() {
-    Span span = tracer.spanBuilder(SPAN_NAME).setSampler(Samplers.alwaysSample()).startSpan();
+  public Span startEndSampledRootSpan(Data data) {
+    Span span = data.tracer.spanBuilder(SPAN_NAME).setSampler(Samplers.alwaysSample()).startSpan();
     span.end();
     return span;
   }
@@ -99,10 +118,10 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndNonSampledChildSpan() {
+  public Span startEndNonSampledChildSpan(Data data) {
     Span span =
-        tracer
-            .spanBuilderWithExplicitParent(SPAN_NAME, rootSpan)
+        data.tracer
+            .spanBuilderWithExplicitParent(SPAN_NAME, data.rootSpan)
             .setSampler(Samplers.neverSample())
             .startSpan();
     span.end();
@@ -116,10 +135,10 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndRecordEventsChildSpan() {
+  public Span startEndRecordEventsChildSpan(Data data) {
     Span span =
-        tracer
-            .spanBuilderWithExplicitParent(SPAN_NAME, rootSpan)
+        data.tracer
+            .spanBuilderWithExplicitParent(SPAN_NAME, data.rootSpan)
             .setSampler(Samplers.neverSample())
             .setRecordEvents(true)
             .startSpan();
@@ -133,10 +152,10 @@ public class StartEndSpanBenchmark {
   @Benchmark
   @BenchmarkMode(Mode.SampleTime)
   @OutputTimeUnit(TimeUnit.NANOSECONDS)
-  public Span startEndSampledChildSpan() {
+  public Span startEndSampledChildSpan(Data data) {
     Span span =
-        tracer
-            .spanBuilderWithExplicitParent(SPAN_NAME, rootSpan)
+        data.tracer
+            .spanBuilderWithExplicitParent(SPAN_NAME, data.rootSpan)
             .setSampler(Samplers.alwaysSample())
             .startSpan();
     span.end();