Add functionality to MemoryProfiler to do multiple garbage collections at the end of the build in an effort to get an accurate measurement of used memory.

PiperOrigin-RevId: 187337487

3 files changed, 99 insertions, 13 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/BUILD b/src/test/java/com/google/devtools/build/lib/BUILD
index 9f741f6503..72f1f9fd6c 100644
--- a/src/test/java/com/google/devtools/build/lib/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/BUILD
@@ -977,7 +977,9 @@ java_test(
         "//src/main/java/com/google/devtools/build/lib/profiler",
         "//src/main/java/com/google/devtools/build/lib/profiler:profiler-output",
         "//src/main/java/com/google/devtools/build/lib/vfs",
+        "//third_party:guava",
         "//third_party:jsr305",
+        "//third_party:mockito",
     ],
 )
 
diff --git a/src/test/java/com/google/devtools/build/lib/profiler/MemoryProfilerTest.java b/src/test/java/com/google/devtools/build/lib/profiler/MemoryProfilerTest.java
new file mode 100644
index 0000000000..c00a1336ca
--- /dev/null
+++ b/src/test/java/com/google/devtools/build/lib/profiler/MemoryProfilerTest.java
@@ -0,0 +1,78 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// 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 com.google.devtools.build.lib.profiler;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import com.google.common.io.ByteStreams;
+import com.google.devtools.build.lib.profiler.MemoryProfiler.MemoryProfileStableHeapParameters;
+import com.google.devtools.build.lib.profiler.MemoryProfiler.Sleeper;
+import java.lang.management.MemoryMXBean;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.mockito.Mockito;
+
+/** Tests for {@link MemoryProfiler}. */
+@RunWith(JUnit4.class)
+public class MemoryProfilerTest {
+  @Test
+  public void profilerDoesOneGcAndNoSleepNormally() throws Exception {
+    MemoryProfiler profiler = MemoryProfiler.instance();
+    profiler.setStableMemoryParameters(
+        new MemoryProfileStableHeapParameters.Converter().convert("1,10"));
+    profiler.start(ByteStreams.nullOutputStream());
+    MemoryMXBean bean = Mockito.mock(MemoryMXBean.class);
+    RecordingSleeper sleeper = new RecordingSleeper();
+    profiler.prepareBean(ProfilePhase.ANALYZE, bean, sleeper);
+    assertThat(sleeper.sleeps).isEmpty();
+    verify(bean, times(1)).gc();
+    profiler.prepareBean(ProfilePhase.FINISH, bean, sleeper);
+    verify(bean, times(2)).gc();
+    assertThat(sleeper.sleeps).isEmpty();
+  }
+
+  @Test
+  public void profilerDoesOneGcAndNoSleepExceptInFinish() throws Exception {
+    MemoryProfiler profiler = MemoryProfiler.instance();
+    profiler.setStableMemoryParameters(
+        new MemoryProfileStableHeapParameters.Converter().convert("3,10"));
+    profiler.start(ByteStreams.nullOutputStream());
+    MemoryMXBean bean = Mockito.mock(MemoryMXBean.class);
+    RecordingSleeper sleeper = new RecordingSleeper();
+    profiler.prepareBean(ProfilePhase.ANALYZE, bean, sleeper);
+    assertThat(sleeper.sleeps).isEmpty();
+    verify(bean, times(1)).gc();
+    profiler.prepareBean(ProfilePhase.FINISH, bean, sleeper);
+    assertThat(sleeper.sleeps)
+        .containsExactly(Duration.ofSeconds(10), Duration.ofSeconds(10))
+        .inOrder();
+    verify(bean, times(4)).gc();
+  }
+
+  private static class RecordingSleeper implements Sleeper {
+    private final List<Duration> sleeps = new ArrayList<>();
+
+    @Override
+    public void sleep(Duration duration) {
+      sleeps.add(duration);
+    }
+  }
+}
diff --git a/src/test/java/com/google/devtools/build/lib/profiler/ProfilerTest.java b/src/test/java/com/google/devtools/build/lib/profiler/ProfilerTest.java
index 2f988dd96a..ffc7e7f31a 100644
--- a/src/test/java/com/google/devtools/build/lib/profiler/ProfilerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/profiler/ProfilerTest.java
@@ -308,19 +308,25 @@ public class ProfilerTest extends FoundationTestCase {
     thread1.join();
     clock.advanceMillis(1);
     profiler.markPhase(ProfilePhase.ANALYZE);
-    Thread thread2 = new Thread() {
-      @Override public void run() {
-        profiler.startTask(ProfilerTask.TEST, "complex task");
-        for (int i = 0; i < 100; i++) {
-          Profiler.instance().logEvent(ProfilerTask.TEST, "thread2a");
-        }
-        profiler.completeTask(ProfilerTask.TEST);
-        profiler.markPhase(ProfilePhase.EXECUTE);
-        for (int i = 0; i < 100; i++) {
-          Profiler.instance().logEvent(ProfilerTask.TEST, "thread2b");
-        }
-      }
-    };
+    Thread thread2 =
+        new Thread() {
+          @Override
+          public void run() {
+            profiler.startTask(ProfilerTask.TEST, "complex task");
+            for (int i = 0; i < 100; i++) {
+              Profiler.instance().logEvent(ProfilerTask.TEST, "thread2a");
+            }
+            profiler.completeTask(ProfilerTask.TEST);
+            try {
+              profiler.markPhase(ProfilePhase.EXECUTE);
+            } catch (InterruptedException e) {
+              throw new IllegalStateException(e);
+            }
+            for (int i = 0; i < 100; i++) {
+              Profiler.instance().logEvent(ProfilerTask.TEST, "thread2b");
+            }
+          }
+        };
     thread2.start();
     thread2.join();
     profiler.logEvent(ProfilerTask.TEST, "last task");