8157728: Convert GCTimer_test to GTest
authorkzhaldyb
Mon, 29 Oct 2018 14:04:42 -0700
changeset 52321 52d3bb5ba2f7
parent 52320 26777794ade5
child 52322 3d33e20a5794
8157728: Convert GCTimer_test to GTest Reviewed-by: tschatzl, jcbeyler, iignatyev
src/hotspot/share/gc/shared/gcTimer.cpp
src/hotspot/share/gc/shared/gcTimer.hpp
src/hotspot/share/utilities/internalVMTests.cpp
src/hotspot/share/utilities/ticks.hpp
test/hotspot/gtest/gc/shared/test_gcTimer.cpp
--- a/src/hotspot/share/gc/shared/gcTimer.cpp	Mon Oct 29 13:58:29 2018 -0700
+++ b/src/hotspot/share/gc/shared/gcTimer.cpp	Mon Oct 29 14:04:42 2018 -0700
@@ -182,214 +182,3 @@
   assert(has_next(), "Must have phases left");
   return _time_partitions->phase_at(_next++);
 }
-
-
-/////////////// Unit tests ///////////////
-
-#ifndef PRODUCT
-
-class TimePartitionPhasesIteratorTest {
- public:
-  static void all() {
-    one_pause();
-    two_pauses();
-    one_sub_pause_phase();
-    many_sub_pause_phases();
-    many_sub_pause_phases2();
-    max_nested_pause_phases();
-    one_concurrent();
-  }
-
-  static void validate_gc_phase(GCPhase* phase, int level, const char* name, const Ticks& start, const Ticks& end) {
-    assert(phase->level() == level, "Incorrect level");
-    assert(strcmp(phase->name(), name) == 0, "Incorrect name");
-    assert(phase->start() == start, "Incorrect start");
-    assert(phase->end() == end, "Incorrect end");
-  }
-
-  static void one_pause() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase", 2);
-    time_partitions.report_gc_phase_end(8);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase", 2, 8);
-    assert(time_partitions.sum_of_pauses() == Ticks(8) - Ticks(2), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(8) - Ticks(2), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void two_pauses() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase1", 2);
-    time_partitions.report_gc_phase_end(3);
-    time_partitions.report_gc_phase_start("PausePhase2", 4);
-    time_partitions.report_gc_phase_end(6);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase1", 2, 3);
-    validate_gc_phase(iter.next(), 0, "PausePhase2", 4, 6);
-
-    assert(time_partitions.sum_of_pauses() == Ticks(3) - Ticks(0), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(2) - Ticks(0), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void one_sub_pause_phase() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase", 2);
-    time_partitions.report_gc_phase_start("SubPhase", 3);
-    time_partitions.report_gc_phase_end(4);
-    time_partitions.report_gc_phase_end(5);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase", 2, 5);
-    validate_gc_phase(iter.next(), 1, "SubPhase", 3, 4);
-
-    assert(time_partitions.sum_of_pauses() == Ticks(3) - Ticks(0), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(3) - Ticks(0), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void max_nested_pause_phases() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase", 2);
-    time_partitions.report_gc_phase_start("SubPhase1", 3);
-    time_partitions.report_gc_phase_start("SubPhase2", 4);
-    time_partitions.report_gc_phase_start("SubPhase3", 5);
-    time_partitions.report_gc_phase_end(6);
-    time_partitions.report_gc_phase_end(7);
-    time_partitions.report_gc_phase_end(8);
-    time_partitions.report_gc_phase_end(9);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase", 2, 9);
-    validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 8);
-    validate_gc_phase(iter.next(), 2, "SubPhase2", 4, 7);
-    validate_gc_phase(iter.next(), 3, "SubPhase3", 5, 6);
-
-    assert(time_partitions.sum_of_pauses() == Ticks(7) - Ticks(0), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(7) - Ticks(0), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void many_sub_pause_phases() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase", 2);
-
-    time_partitions.report_gc_phase_start("SubPhase1", 3);
-    time_partitions.report_gc_phase_end(4);
-    time_partitions.report_gc_phase_start("SubPhase2", 5);
-    time_partitions.report_gc_phase_end(6);
-    time_partitions.report_gc_phase_start("SubPhase3", 7);
-    time_partitions.report_gc_phase_end(8);
-    time_partitions.report_gc_phase_start("SubPhase4", 9);
-    time_partitions.report_gc_phase_end(10);
-
-    time_partitions.report_gc_phase_end(11);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase", 2, 11);
-    validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 4);
-    validate_gc_phase(iter.next(), 1, "SubPhase2", 5, 6);
-    validate_gc_phase(iter.next(), 1, "SubPhase3", 7, 8);
-    validate_gc_phase(iter.next(), 1, "SubPhase4", 9, 10);
-
-    assert(time_partitions.sum_of_pauses() == Ticks(9) - Ticks(0), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(9) - Ticks(0), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void many_sub_pause_phases2() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("PausePhase", 2);
-
-    time_partitions.report_gc_phase_start("SubPhase1", 3);
-    time_partitions.report_gc_phase_start("SubPhase11", 4);
-    time_partitions.report_gc_phase_end(5);
-    time_partitions.report_gc_phase_start("SubPhase12", 6);
-    time_partitions.report_gc_phase_end(7);
-    time_partitions.report_gc_phase_end(8);
-    time_partitions.report_gc_phase_start("SubPhase2", 9);
-    time_partitions.report_gc_phase_start("SubPhase21", 10);
-    time_partitions.report_gc_phase_end(11);
-    time_partitions.report_gc_phase_start("SubPhase22", 12);
-    time_partitions.report_gc_phase_end(13);
-    time_partitions.report_gc_phase_end(14);
-    time_partitions.report_gc_phase_start("SubPhase3", 15);
-    time_partitions.report_gc_phase_end(16);
-
-    time_partitions.report_gc_phase_end(17);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "PausePhase", 2, 17);
-    validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 8);
-    validate_gc_phase(iter.next(), 2, "SubPhase11", 4, 5);
-    validate_gc_phase(iter.next(), 2, "SubPhase12", 6, 7);
-    validate_gc_phase(iter.next(), 1, "SubPhase2", 9, 14);
-    validate_gc_phase(iter.next(), 2, "SubPhase21", 10, 11);
-    validate_gc_phase(iter.next(), 2, "SubPhase22", 12, 13);
-    validate_gc_phase(iter.next(), 1, "SubPhase3", 15, 16);
-
-    assert(time_partitions.sum_of_pauses() == Ticks(15) - Ticks(0), "Incorrect");
-    assert(time_partitions.longest_pause() == Ticks(15) - Ticks(0), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-
-  static void one_concurrent() {
-    TimePartitions time_partitions;
-    time_partitions.report_gc_phase_start("ConcurrentPhase", 2, GCPhase::ConcurrentPhaseType);
-    time_partitions.report_gc_phase_end(8, GCPhase::ConcurrentPhaseType);
-
-    TimePartitionPhasesIterator iter(&time_partitions);
-
-    validate_gc_phase(iter.next(), 0, "ConcurrentPhase", 2, 8);
-    // ConcurrentPhaseType should not affect to both 'sum_of_pauses()' and 'longest_pause()'.
-    assert(time_partitions.sum_of_pauses() == Tickspan(), "Incorrect");
-    assert(time_partitions.longest_pause() == Tickspan(), "Incorrect");
-
-    assert(!iter.has_next(), "Too many elements");
-  }
-};
-
-class GCTimerTest {
-public:
-  static void all() {
-    gc_start();
-    gc_end();
-  }
-
-  static void gc_start() {
-    GCTimer gc_timer;
-    gc_timer.register_gc_start(1);
-
-    assert(gc_timer.gc_start() == Ticks(1), "Incorrect");
-  }
-
-  static void gc_end() {
-    GCTimer gc_timer;
-    gc_timer.register_gc_start(1);
-    gc_timer.register_gc_end(2);
-
-    assert(gc_timer.gc_end() == Ticks(2), "Incorrect");
-  }
-};
-
-void GCTimer_test() {
-  GCTimerTest::all();
-  TimePartitionPhasesIteratorTest::all();
-}
-
-#endif
--- a/src/hotspot/share/gc/shared/gcTimer.hpp	Mon Oct 29 13:58:29 2018 -0700
+++ b/src/hotspot/share/gc/shared/gcTimer.hpp	Mon Oct 29 14:04:42 2018 -0700
@@ -129,7 +129,6 @@
 };
 
 class GCTimer : public ResourceObj {
-  NOT_PRODUCT(friend class GCTimerTest;)
  protected:
   Ticks _gc_start;
   Ticks _gc_end;
--- a/src/hotspot/share/utilities/internalVMTests.cpp	Mon Oct 29 13:58:29 2018 -0700
+++ b/src/hotspot/share/utilities/internalVMTests.cpp	Mon Oct 29 14:04:42 2018 -0700
@@ -44,7 +44,6 @@
   tty->print_cr("Running internal VM tests");
   run_unit_test(TestReserveMemorySpecial_test);
   run_unit_test(TestMetaspaceUtils_test);
-  run_unit_test(GCTimer_test);
   tty->print_cr("All internal VM tests passed");
 }
 
--- a/src/hotspot/share/utilities/ticks.hpp	Mon Oct 29 13:58:29 2018 -0700
+++ b/src/hotspot/share/utilities/ticks.hpp	Mon Oct 29 14:04:42 2018 -0700
@@ -233,7 +233,7 @@
   TimeInstant(jlong ticks) : Rep<TimeSource>(ticks) {}
   friend class GranularTimer;
   friend class ObjectSample;
-  //  GC VM tests
+  // GC unit tests
   friend class TimePartitionPhasesIteratorTest;
   friend class GCTimerTest;
 };
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/gtest/gc/shared/test_gcTimer.cpp	Mon Oct 29 14:04:42 2018 -0700
@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) 2001, 2018, 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.
+ */
+
+#include "precompiled.hpp"
+#include "gc/shared/gcTimer.hpp"
+#include "utilities/ticks.hpp"
+#include "unittest.hpp"
+
+class GCTimerTest {
+ public:
+  static void register_gc_start(GCTimer* const timer, jlong ticks) {
+    timer->register_gc_start(Ticks(ticks));
+  }
+  static void register_gc_end(GCTimer* const timer, jlong ticks) {
+    timer->register_gc_end(Ticks(ticks));
+  }
+};
+
+TEST(GCTimer, start) {
+  GCTimer gc_timer;
+  GCTimerTest::register_gc_start(&gc_timer, 1);
+
+  EXPECT_EQ(1, gc_timer.gc_start().value());
+}
+
+TEST(GCTimer, end) {
+  GCTimer gc_timer;
+
+  GCTimerTest::register_gc_start(&gc_timer, 1);
+  GCTimerTest::register_gc_end(&gc_timer, 2);
+
+  EXPECT_EQ(2, gc_timer.gc_end().value());
+}
+
+class TimePartitionPhasesIteratorTest {
+ public:
+
+  static void validate_gc_phase(GCPhase* phase, int level, const char* name, const jlong& start, const jlong& end) {
+    EXPECT_EQ(level, phase->level());
+    EXPECT_STREQ(name, phase->name());
+    EXPECT_EQ(start, phase->start().value());
+    EXPECT_EQ(end, phase->end().value());
+  }
+
+  static void validate_pauses(const TimePartitions& time_partitions, const Tickspan& expected_sum_of_pauses, const Tickspan& expected_longest_pause) {
+    EXPECT_EQ(expected_sum_of_pauses, time_partitions.sum_of_pauses());
+    EXPECT_EQ(expected_longest_pause, time_partitions.longest_pause());
+  }
+  static void validate_pauses(const TimePartitions& time_partitions, const Tickspan& expected_pause) {
+    TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, expected_pause, expected_pause);
+  }
+  static void validate_pauses(const TimePartitions& time_partitions, jlong end, jlong start) {
+    TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, Ticks(end) - Ticks(start));
+  }
+  static void validate_pauses(const TimePartitions& time_partitions, jlong all_end, jlong all_start, jlong longest_end, jlong longest_start) {
+    TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, Ticks(all_end) - Ticks(all_start), Ticks(longest_end) - Ticks(longest_start));
+  }
+
+  static void report_gc_phase_start(TimePartitions* const partitions, const char* name, jlong ticks, GCPhase::PhaseType type=GCPhase::PausePhaseType) {
+    partitions->report_gc_phase_start(name, Ticks(ticks), type);
+  }
+
+  static void report_gc_phase_end(TimePartitions* const partitions, jlong ticks, GCPhase::PhaseType type=GCPhase::PausePhaseType) {
+    partitions->report_gc_phase_end(Ticks(ticks), type);
+  }
+};
+
+TEST(TimePartitionPhasesIterator, one_pause) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase", 2);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 8);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase", 2, 8));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 8, 2));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, two_pauses) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase1", 2);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 3);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase2", 4);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 6);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase1", 2, 3));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase2", 4, 6));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 3, 0, 2, 0));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, one_sub_pause_phase) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase", 2);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase", 3);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 4);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 5);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase", 2, 5));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase", 3, 4));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 3, 0));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, max_nested_pause_phases) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase", 2);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase1", 3);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase2", 4);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase3", 5);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 6);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 7);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 8);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 9);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase", 2, 9));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 8));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 2, "SubPhase2", 4, 7));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 3, "SubPhase3", 5, 6));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 7, 0));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, many_sub_pause_phases) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase", 2);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase1", 3);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 4);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase2", 5);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 6);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase3", 7);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 8);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase4", 9);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 10);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 11);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase", 2, 11));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 4));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase2", 5, 6));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase3", 7, 8));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase4", 9, 10));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 9, 0));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, many_sub_pause_phases2) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "PausePhase", 2);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase1", 3);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase11", 4);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 5);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase12", 6);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 7);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 8);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase2", 9);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase21", 10);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 11);
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase22", 12);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 13);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 14);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "SubPhase3", 15);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 16);
+
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 17);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "PausePhase", 2, 17));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase1", 3, 8));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 2, "SubPhase11", 4, 5));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 2, "SubPhase12", 6, 7));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase2", 9, 14));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 2, "SubPhase21", 10, 11));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 2, "SubPhase22", 12, 13));
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 1, "SubPhase3", 15, 16));
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, 15, 0));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}
+
+TEST(TimePartitionPhasesIterator, one_concurrent) {
+  TimePartitions time_partitions;
+  TimePartitionPhasesIteratorTest::report_gc_phase_start(&time_partitions, "ConcurrentPhase", 2, GCPhase::ConcurrentPhaseType);
+  TimePartitionPhasesIteratorTest::report_gc_phase_end(&time_partitions, 8, GCPhase::ConcurrentPhaseType);
+
+  TimePartitionPhasesIterator iter(&time_partitions);
+
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_gc_phase(iter.next(), 0, "ConcurrentPhase", 2, 8));
+  // ConcurrentPhaseType should not affect to both 'sum_of_pauses()' and 'longest_pause()'.
+  EXPECT_NO_FATAL_FAILURE(TimePartitionPhasesIteratorTest::validate_pauses(time_partitions, Tickspan()));
+
+  EXPECT_FALSE(iter.has_next()) << "Too many elements";
+}