From f4c07b9ce06a6d0b08be073bb793324d6117a905 Mon Sep 17 00:00:00 2001
From: Jacob Trimble <modmaker@google.com>
Date: Tue, 20 Oct 2020 14:08:46 -0700
Subject: [PATCH] Work around non-deterministic tests.

We currently have a bug about non-deterministic output in the MPD
generator.  This works around that bug by optionally doing everything
in a single thread.  This allows us to run manifest comparisons without
making the major changes needed to add that feature.

Issue #177

Change-Id: I10e1084dac77841220161fbd2575cdcb5c13c00e
---
 packager/app/job_manager.h                    |  8 ++-
 packager/app/packager_main.cc                 |  4 ++
 packager/app/single_thread_job_manager.cc     | 34 +++++++++++
 packager/app/single_thread_job_manager.h      | 32 ++++++++++
 packager/app/test/packager_test.py            | 47 ++-------------
 .../output.mpd                                | 20 +++----
 .../output.mpd                                | 60 +++++++++----------
 .../output.mpd                                | 24 ++++----
 .../hls-only-dash-only-captions/output.mpd    | 24 ++++----
 .../output.mpd                                | 40 ++++++-------
 .../testdata/video-audio-webvtt/output.mpd    | 20 +++----
 .../vtt-text-to-mp4-with-ad-cues/output.mpd   | 50 ++++++++--------
 packager/packager.cc                          |  9 ++-
 packager/packager.gyp                         |  2 +
 packager/packager.h                           |  3 +
 15 files changed, 213 insertions(+), 164 deletions(-)
 create mode 100644 packager/app/single_thread_job_manager.cc
 create mode 100644 packager/app/single_thread_job_manager.h

diff --git a/packager/app/job_manager.h b/packager/app/job_manager.h
index 09a7c20554..1f40e7116f 100644
--- a/packager/app/job_manager.h
+++ b/packager/app/job_manager.h
@@ -60,6 +60,8 @@ class JobManager {
   //        fails or is cancelled. It can be NULL.
   explicit JobManager(std::unique_ptr<SyncPointQueue> sync_points);
 
+  virtual ~JobManager() = default;
+
   // Create a new job entry by specifying the origin handler at the top of the
   // chain and a name for the thread. This will only register the job. To start
   // the job, you need to call |RunJobs|.
@@ -68,12 +70,12 @@ class JobManager {
   // Initialize all registered jobs. If any job fails to initialize, this will
   // return the error and it will not be safe to call |RunJobs| as not all jobs
   // will be properly initialized.
-  Status InitializeJobs();
+  virtual Status InitializeJobs();
 
   // Run all registered jobs. Before calling this make sure that
   // |InitializedJobs| returned |Status::OK|. This call is blocking and will
   // block until all jobs exit.
-  Status RunJobs();
+  virtual Status RunJobs();
 
   // Ask all jobs to stop running. This call is non-blocking and can be used to
   // unblock a call to |RunJobs|.
@@ -81,7 +83,7 @@ class JobManager {
 
   SyncPointQueue* sync_points() { return sync_points_.get(); }
 
- private:
+ protected:
   JobManager(const JobManager&) = delete;
   JobManager& operator=(const JobManager&) = delete;
 
diff --git a/packager/app/packager_main.cc b/packager/app/packager_main.cc
index 9d5c8b7af4..b6f1add2e0 100644
--- a/packager/app/packager_main.cc
+++ b/packager/app/packager_main.cc
@@ -48,6 +48,9 @@ DEFINE_bool(use_fake_clock_for_muxer,
 DEFINE_string(test_packager_version,
               "",
               "Packager version for testing. Should be used for testing only.");
+DEFINE_bool(single_threaded,
+            false,
+            "If enabled, only use one thread when generating content.");
 
 namespace shaka {
 namespace {
@@ -311,6 +314,7 @@ base::Optional<PackagingParams> GetPackagingParams() {
   PackagingParams packaging_params;
 
   packaging_params.temp_dir = FLAGS_temp_dir;
+  packaging_params.single_threaded = FLAGS_single_threaded;
 
   AdCueGeneratorParams& ad_cue_generator_params =
       packaging_params.ad_cue_generator_params;
diff --git a/packager/app/single_thread_job_manager.cc b/packager/app/single_thread_job_manager.cc
new file mode 100644
index 0000000000..0d0c3a8b85
--- /dev/null
+++ b/packager/app/single_thread_job_manager.cc
@@ -0,0 +1,34 @@
+// Copyright 2020 Google LLLC All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+#include "packager/app/single_thread_job_manager.h"
+
+#include "packager/media/chunking/sync_point_queue.h"
+#include "packager/media/origin/origin_handler.h"
+
+namespace shaka {
+namespace media {
+
+SingleThreadJobManager::SingleThreadJobManager(
+    std::unique_ptr<SyncPointQueue> sync_points)
+    : JobManager(std::move(sync_points)) {}
+
+Status SingleThreadJobManager::InitializeJobs() {
+  Status status;
+  for (const JobEntry& job_entry : job_entries_)
+    status.Update(job_entry.worker->Initialize());
+  return status;
+}
+
+Status SingleThreadJobManager::RunJobs() {
+  Status status;
+  for (const JobEntry& job_entry : job_entries_)
+    status.Update(job_entry.worker->Run());
+  return status;
+}
+
+}  // namespace media
+}  // namespace shaka
diff --git a/packager/app/single_thread_job_manager.h b/packager/app/single_thread_job_manager.h
new file mode 100644
index 0000000000..fa99e89428
--- /dev/null
+++ b/packager/app/single_thread_job_manager.h
@@ -0,0 +1,32 @@
+// Copyright 2020 Google LLLC All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file or at
+// https://developers.google.com/open-source/licenses/bsd
+
+#ifndef PACKAGER_APP_SINGLE_THREAD_JOB_MANAGER_H_
+#define PACKAGER_APP_SINGLE_THREAD_JOB_MANAGER_H_
+
+#include <memory>
+
+#include "packager/app/job_manager.h"
+
+namespace shaka {
+namespace media {
+
+// A subclass of JobManager that runs all the jobs in a single thread.
+class SingleThreadJobManager : public JobManager {
+ public:
+  // @param sync_points is an optional SyncPointQueue used to synchronize and
+  //        align cue points. JobManager cancels @a sync_points when any job
+  //        fails or is cancelled. It can be NULL.
+  explicit SingleThreadJobManager(std::unique_ptr<SyncPointQueue> sync_points);
+
+  Status InitializeJobs() override;
+  Status RunJobs() override;
+};
+
+}  // namespace media
+}  // namespace shaka
+
+#endif  // PACKAGER_APP_SINGLE_THREAD_JOB_MANAGER_H_
diff --git a/packager/app/test/packager_test.py b/packager/app/test/packager_test.py
index 3c83be4eb2..7ceb670fcf 100755
--- a/packager/app/test/packager_test.py
+++ b/packager/app/test/packager_test.py
@@ -477,7 +477,7 @@ class PackagerAppTest(unittest.TestCase):
                 segment_duration=1.0,
                 use_fake_clock=True,
                 allow_codec_switching=False):
-    flags = []
+    flags = ['--single_threaded']
 
     if not strip_parameter_set_nalus:
       flags += ['--strip_parameter_set_nalus=false']
@@ -767,14 +767,7 @@ class PackagerFunctionalTest(PackagerAppTest):
     streams = audio_video_streams + dash_text_stream + hls_text_stream
     self.assertPackageSuccess(streams, self._GetFlags(output_dash=True,
                                                       output_hls=True))
-    # Mpd cannot be validated right now since we don't generate deterministic
-    # mpd with multiple inputs due to thread racing.
-    # TODO(b/73349711): Generate deterministic mpd or at least validate mpd
-    #                   schema.
-    self._CheckTestResults(
-        'hls-only-dash-only-captions',
-        diff_files_policy=DiffFilesPolicy(
-            allowed_diff_files=['output.mpd'], exact=False))
+    self._CheckTestResults('hls-only-dash-only-captions')
 
   def testDashOnlyAndHlsOnly(self):
     streams = [
@@ -1241,14 +1234,7 @@ class PackagerFunctionalTest(PackagerAppTest):
     flags = self._GetFlags(output_dash=True, output_hls=True,
                            generate_static_live_mpd=True, ad_cues='1.5')
     self.assertPackageSuccess(streams, flags)
-    # Mpd cannot be validated right now since we don't generate determinstic
-    # mpd with multiple inputs due to thread racing.
-    # TODO(b/73349711): Generate determinstic mpd or at least validate mpd
-    #                   schema.
-    self._CheckTestResults(
-        'vtt-text-to-mp4-with-ad-cues',
-        diff_files_policy=DiffFilesPolicy(
-            allowed_diff_files=['output.mpd'], exact=False))
+    self._CheckTestResults('vtt-text-to-mp4-with-ad-cues')
 
   def testWebmSubsampleEncryption(self):
     streams = [
@@ -1621,15 +1607,7 @@ class PackagerFunctionalTest(PackagerAppTest):
     self.assertPackageSuccess(streams,
                               self._GetFlags(output_dash=True,
                                              allow_codec_switching=True))
-    # Mpd cannot be validated right now since we don't generate determinstic
-    # mpd with multiple inputs due to thread racing.
-    # TODO(b/73349711): Generate determinstic mpd or at least validate mpd
-    #                   schema.
-    # See also https://github.com/google/shaka-packager/issues/177.
-    self._CheckTestResults(
-        'audio-video-with-codec-switching',
-        diff_files_policy=DiffFilesPolicy(
-            allowed_diff_files=['output.mpd'], exact=False))
+    self._CheckTestResults('audio-video-with-codec-switching')
 
   def testAllowCodecSwitchingWithEncryptionAndTrickplay(self):
     streams = [
@@ -1645,15 +1623,8 @@ class PackagerFunctionalTest(PackagerAppTest):
                               self._GetFlags(output_dash=True,
                                              allow_codec_switching=True,
                                              encryption=True))
-    # Mpd cannot be validated right now since we don't generate determinstic
-    # mpd with multiple inputs due to thread racing.
-    # TODO(b/73349711): Generate determinstic mpd or at least validate mpd
-    #                   schema.
-    # See also https://github.com/google/shaka-packager/issues/177.
     self._CheckTestResults(
-        'audio-video-with-codec-switching-encryption-trick-play',
-        diff_files_policy=DiffFilesPolicy(
-            allowed_diff_files=['output.mpd'], exact=False))
+        'audio-video-with-codec-switching-encryption-trick-play')
 
   def testLiveProfileAndEncryption(self):
     self.assertPackageSuccess(
@@ -1675,14 +1646,8 @@ class PackagerFunctionalTest(PackagerAppTest):
                          test_files=['bear-1280x720.mp4', 'bear-640x360.mp4',
                                      'bear-320x180.mp4']),
         self._GetFlags(encryption=True, output_dash=True))
-    # Mpd cannot be validated right now since we don't generate determinstic
-    # mpd with multiple inputs due to thread racing.
-    # TODO(b/73349711): Generate determinstic mpd or at least validate mpd
-    #                   schema.
     self._CheckTestResults(
-        'live-profile-and-encryption-and-mult-files',
-        diff_files_policy=DiffFilesPolicy(
-            allowed_diff_files=['output.mpd'], exact=False))
+        'live-profile-and-encryption-and-mult-files')
 
   def testLiveProfileAndKeyRotation(self):
     self.assertPackageSuccess(
diff --git a/packager/app/test/testdata/audio-video-with-accessibilities-and-roles/output.mpd b/packager/app/test/testdata/audio-video-with-accessibilities-and-roles/output.mpd
index 4cc940fcee..c6de0c9286 100644
--- a/packager/app/test/testdata/audio-video-with-accessibilities-and-roles/output.mpd
+++ b/packager/app/test/testdata/audio-video-with-accessibilities-and-roles/output.mpd
@@ -2,24 +2,18 @@
 <!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
 <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.7360665798187256S">
   <Period id="0">
-    <AdaptationSet id="0" contentType="text" subsegmentAlignment="true">
-      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="caption"/>
-      <Representation id="0" bandwidth="273" mimeType="text/vtt">
-        <BaseURL>bear-english-text.vtt</BaseURL>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
-      <Representation id="1" bandwidth="973483" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+      <Representation id="0" bandwidth="973483" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
         <BaseURL>bear-640x360-video.mp4</BaseURL>
         <SegmentBase indexRange="863-930" timescale="30000">
           <Initialization range="0-862"/>
         </SegmentBase>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="2" contentType="audio" subsegmentAlignment="true">
+    <AdaptationSet id="1" contentType="audio" subsegmentAlignment="true">
       <Accessibility schemeIdUri="urn:tva:metadata:cs:AudioPurposeCS:2007" value="1"/>
       <Role schemeIdUri="urn:mpeg:dash:role:2011" value="alternate"/>
-      <Representation id="2" bandwidth="133334" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+      <Representation id="1" bandwidth="133334" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <BaseURL>bear-640x360-audio.mp4</BaseURL>
         <SegmentBase indexRange="797-864" timescale="44100">
@@ -27,5 +21,11 @@
         </SegmentBase>
       </Representation>
     </AdaptationSet>
+    <AdaptationSet id="2" contentType="text" subsegmentAlignment="true">
+      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="caption"/>
+      <Representation id="2" bandwidth="273" mimeType="text/vtt">
+        <BaseURL>bear-english-text.vtt</BaseURL>
+      </Representation>
+    </AdaptationSet>
   </Period>
 </MPD>
diff --git a/packager/app/test/testdata/audio-video-with-codec-switching-encryption-trick-play/output.mpd b/packager/app/test/testdata/audio-video-with-codec-switching-encryption-trick-play/output.mpd
index 2893b62da0..e9c2a74c72 100644
--- a/packager/app/test/testdata/audio-video-with-codec-switching-encryption-trick-play/output.mpd
+++ b/packager/app/test/testdata/audio-video-with-codec-switching-encryption-trick-play/output.mpd
@@ -2,50 +2,50 @@
 <!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
 <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" xmlns:cenc="urn:mpeg:cenc:2013" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.802799940109253S">
   <Period id="0">
-    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+    <AdaptationSet id="0" contentType="video" maxWidth="1280" maxHeight="720" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
       <ContentProtection value="cenc" schemeIdUri="urn:mpeg:dash:mp4protection:2011" cenc:default_KID="31323334-3536-3738-3930-313233343536"/>
       <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b">
         <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
       </ContentProtection>
-      <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="1"/>
+      <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="2"/>
       <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-      <Representation id="0" bandwidth="281671" codecs="hev1.1.6.L63.90" mimeType="video/mp4" sar="1:1">
-        <BaseURL>bear-640x360-hevc-video.mp4</BaseURL>
-        <SegmentBase indexRange="3215-3282" timescale="30000">
-          <Initialization range="0-3214"/>
+      <Representation id="0" bandwidth="2631545" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" width="1280" height="720">
+        <BaseURL>bear-1280x720-video.mp4</BaseURL>
+        <SegmentBase indexRange="1129-1196" timescale="30000">
+          <Initialization range="0-1128"/>
+        </SegmentBase>
+      </Representation>
+      <Representation id="3" bandwidth="977743" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" width="640" height="360">
+        <BaseURL>bear-640x360-video.mp4</BaseURL>
+        <SegmentBase indexRange="1131-1198" timescale="30000">
+          <Initialization range="0-1130"/>
         </SegmentBase>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" maxWidth="1280" maxHeight="720" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+    <AdaptationSet id="1" contentType="video" width="1280" height="720" frameRate="30000/30030" subsegmentAlignment="true" par="16:9">
+      <ContentProtection value="cenc" schemeIdUri="urn:mpeg:dash:mp4protection:2011" cenc:default_KID="31323334-3536-3738-3930-313233343536"/>
+      <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b">
+        <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
+      </ContentProtection>
+      <EssentialProperty schemeIdUri="http://dashif.org/guidelines/trickmode" value="0"/>
+      <Representation id="1" bandwidth="470530" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" maxPlayoutRate="30" codingDependency="false">
+        <BaseURL>bear-1280x720-video-trick_play_factor_1.mp4</BaseURL>
+        <SegmentBase indexRange="1129-1196" timescale="30000">
+          <Initialization range="0-1128"/>
+        </SegmentBase>
+      </Representation>
+    </AdaptationSet>
+    <AdaptationSet id="2" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
       <ContentProtection value="cenc" schemeIdUri="urn:mpeg:dash:mp4protection:2011" cenc:default_KID="31323334-3536-3738-3930-313233343536"/>
       <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b">
         <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
       </ContentProtection>
       <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="0"/>
       <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-      <Representation id="1" bandwidth="977743" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" width="640" height="360">
-        <BaseURL>bear-640x360-video.mp4</BaseURL>
-        <SegmentBase indexRange="1131-1198" timescale="30000">
-          <Initialization range="0-1130"/>
-        </SegmentBase>
-      </Representation>
-      <Representation id="2" bandwidth="2631545" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" width="1280" height="720">
-        <BaseURL>bear-1280x720-video.mp4</BaseURL>
-        <SegmentBase indexRange="1129-1196" timescale="30000">
-          <Initialization range="0-1128"/>
-        </SegmentBase>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="2" contentType="video" width="1280" height="720" frameRate="30000/30030" subsegmentAlignment="true" par="16:9">
-      <ContentProtection value="cenc" schemeIdUri="urn:mpeg:dash:mp4protection:2011" cenc:default_KID="31323334-3536-3738-3930-313233343536"/>
-      <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b">
-        <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
-      </ContentProtection>
-      <EssentialProperty schemeIdUri="http://dashif.org/guidelines/trickmode" value="1"/>
-      <Representation id="3" bandwidth="470530" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" maxPlayoutRate="30" codingDependency="false">
-        <BaseURL>bear-1280x720-video-trick_play_factor_1.mp4</BaseURL>
-        <SegmentBase indexRange="1129-1196" timescale="30000">
-          <Initialization range="0-1128"/>
+      <Representation id="2" bandwidth="281671" codecs="hev1.1.6.L63.90" mimeType="video/mp4" sar="1:1">
+        <BaseURL>bear-640x360-hevc-video.mp4</BaseURL>
+        <SegmentBase indexRange="3215-3282" timescale="30000">
+          <Initialization range="0-3214"/>
         </SegmentBase>
       </Representation>
     </AdaptationSet>
diff --git a/packager/app/test/testdata/audio-video-with-codec-switching/output.mpd b/packager/app/test/testdata/audio-video-with-codec-switching/output.mpd
index 9241a6c2c8..f399d13106 100644
--- a/packager/app/test/testdata/audio-video-with-codec-switching/output.mpd
+++ b/packager/app/test/testdata/audio-video-with-codec-switching/output.mpd
@@ -2,20 +2,10 @@
 <!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
 <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.802799940109253S">
   <Period id="0">
-    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+    <AdaptationSet id="0" contentType="video" maxWidth="1280" maxHeight="720" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
       <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="1"/>
       <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-      <Representation id="0" bandwidth="277411" codecs="hev1.1.6.L63.90" mimeType="video/mp4" sar="1:1">
-        <BaseURL>bear-640x360-hevc-video.mp4</BaseURL>
-        <SegmentBase indexRange="1903-1970" timescale="30000">
-          <Initialization range="0-1902"/>
-        </SegmentBase>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" maxWidth="1280" maxHeight="720" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
-      <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="0"/>
-      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-      <Representation id="1" bandwidth="2627285" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" width="1280" height="720">
+      <Representation id="0" bandwidth="2627285" codecs="avc1.64001f" mimeType="video/mp4" sar="1:1" width="1280" height="720">
         <BaseURL>bear-1280x720-video.mp4</BaseURL>
         <SegmentBase indexRange="862-929" timescale="30000">
           <Initialization range="0-861"/>
@@ -28,6 +18,16 @@
         </SegmentBase>
       </Representation>
     </AdaptationSet>
+    <AdaptationSet id="1" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+      <SupplementalProperty schemeIdUri="urn:mpeg:dash:adaptation-set-switching:2016" value="0"/>
+      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
+      <Representation id="1" bandwidth="277411" codecs="hev1.1.6.L63.90" mimeType="video/mp4" sar="1:1">
+        <BaseURL>bear-640x360-hevc-video.mp4</BaseURL>
+        <SegmentBase indexRange="1903-1970" timescale="30000">
+          <Initialization range="0-1902"/>
+        </SegmentBase>
+      </Representation>
+    </AdaptationSet>
     <AdaptationSet id="2" contentType="audio" subsegmentAlignment="true">
       <Representation id="3" bandwidth="133334" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
diff --git a/packager/app/test/testdata/hls-only-dash-only-captions/output.mpd b/packager/app/test/testdata/hls-only-dash-only-captions/output.mpd
index 6bb2ccbbd3..1644042a48 100644
--- a/packager/app/test/testdata/hls-only-dash-only-captions/output.mpd
+++ b/packager/app/test/testdata/hls-only-dash-only-captions/output.mpd
@@ -12,18 +12,8 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="1" contentType="text" segmentAlignment="true">
-      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
-      <Representation id="1" bandwidth="2056" codecs="wvtt" mimeType="application/mp4">
-        <SegmentTemplate timescale="1000" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="1">
-          <SegmentTimeline>
-            <S t="0" d="1000" r="4"/>
-          </SegmentTimeline>
-        </SegmentTemplate>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="2" contentType="audio" segmentAlignment="true">
-      <Representation id="2" bandwidth="133961" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+    <AdaptationSet id="1" contentType="audio" segmentAlignment="true">
+      <Representation id="1" bandwidth="133961" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <SegmentTemplate timescale="44100" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
@@ -34,5 +24,15 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
+    <AdaptationSet id="2" contentType="text" segmentAlignment="true">
+      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
+      <Representation id="2" bandwidth="2056" codecs="wvtt" mimeType="application/mp4">
+        <SegmentTemplate timescale="1000" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="1">
+          <SegmentTimeline>
+            <S t="0" d="1000" r="4"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
+    </AdaptationSet>
   </Period>
 </MPD>
diff --git a/packager/app/test/testdata/live-profile-and-encryption-and-mult-files/output.mpd b/packager/app/test/testdata/live-profile-and-encryption-and-mult-files/output.mpd
index bdf40745c9..c0180e6e66 100644
--- a/packager/app/test/testdata/live-profile-and-encryption-and-mult-files/output.mpd
+++ b/packager/app/test/testdata/live-profile-and-encryption-and-mult-files/output.mpd
@@ -15,14 +15,6 @@
           </SegmentTimeline>
         </SegmentTemplate>
       </Representation>
-      <Representation id="1" bandwidth="978414" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" width="640" height="360">
-        <SegmentTemplate timescale="30000" initialization="bear-640x360-video-init.mp4" media="bear-640x360-video-$Number$.m4s" startNumber="1">
-          <SegmentTimeline>
-            <S t="0" d="30030" r="1"/>
-            <S t="60060" d="22022"/>
-          </SegmentTimeline>
-        </SegmentTemplate>
-      </Representation>
       <Representation id="2" bandwidth="383625" codecs="avc1.64000d" mimeType="video/mp4" sar="1:1" width="320" height="180">
         <SegmentTemplate timescale="30000" initialization="bear-320x180-video-init.mp4" media="bear-320x180-video-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
@@ -31,13 +23,21 @@
           </SegmentTimeline>
         </SegmentTemplate>
       </Representation>
+      <Representation id="4" bandwidth="978414" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1" width="640" height="360">
+        <SegmentTemplate timescale="30000" initialization="bear-640x360-video-init.mp4" media="bear-640x360-video-$Number$.m4s" startNumber="1">
+          <SegmentTimeline>
+            <S t="0" d="30030" r="1"/>
+            <S t="60060" d="22022"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
     </AdaptationSet>
     <AdaptationSet id="1" contentType="audio" segmentAlignment="true">
       <ContentProtection value="cenc" schemeIdUri="urn:mpeg:dash:mp4protection:2011" cenc:default_KID="31323334-3536-3738-3930-313233343536"/>
       <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b">
         <cenc:pssh>AAAANHBzc2gBAAAAEHfv7MCyTQKs4zweUuL7SwAAAAExMjM0NTY3ODkwMTIzNDU2AAAAAA==</cenc:pssh>
       </ContentProtection>
-      <Representation id="3" bandwidth="134304" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+      <Representation id="1" bandwidth="134304" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <SegmentTemplate timescale="44100" initialization="bear-1280x720-audio-init.mp4" media="bear-1280x720-audio-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
@@ -47,17 +47,7 @@
           </SegmentTimeline>
         </SegmentTemplate>
       </Representation>
-      <Representation id="4" bandwidth="134304" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
-        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
-        <SegmentTemplate timescale="44100" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="1">
-          <SegmentTimeline>
-            <S t="0" d="45056"/>
-            <S t="45056" d="44032"/>
-            <S t="89088" d="31744"/>
-          </SegmentTimeline>
-        </SegmentTemplate>
-      </Representation>
-      <Representation id="5" bandwidth="134047" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+      <Representation id="3" bandwidth="134047" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <SegmentTemplate timescale="44100" initialization="bear-320x180-audio-init.mp4" media="bear-320x180-audio-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
@@ -67,6 +57,16 @@
           </SegmentTimeline>
         </SegmentTemplate>
       </Representation>
+      <Representation id="5" bandwidth="134304" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
+        <SegmentTemplate timescale="44100" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="1">
+          <SegmentTimeline>
+            <S t="0" d="45056"/>
+            <S t="45056" d="44032"/>
+            <S t="89088" d="31744"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
     </AdaptationSet>
   </Period>
 </MPD>
diff --git a/packager/app/test/testdata/video-audio-webvtt/output.mpd b/packager/app/test/testdata/video-audio-webvtt/output.mpd
index c9506e753f..2e57b85d86 100644
--- a/packager/app/test/testdata/video-audio-webvtt/output.mpd
+++ b/packager/app/test/testdata/video-audio-webvtt/output.mpd
@@ -2,22 +2,16 @@
 <!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
 <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.7360665798187256S">
   <Period id="0">
-    <AdaptationSet id="0" contentType="text" subsegmentAlignment="true">
-      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
-      <Representation id="0" bandwidth="273" mimeType="text/vtt">
-        <BaseURL>bear-english-text.vtt</BaseURL>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
-      <Representation id="1" bandwidth="973483" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" subsegmentAlignment="true" par="16:9">
+      <Representation id="0" bandwidth="973483" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
         <BaseURL>bear-640x360-video.mp4</BaseURL>
         <SegmentBase indexRange="863-930" timescale="30000">
           <Initialization range="0-862"/>
         </SegmentBase>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="2" contentType="audio" subsegmentAlignment="true">
-      <Representation id="2" bandwidth="133334" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+    <AdaptationSet id="1" contentType="audio" subsegmentAlignment="true">
+      <Representation id="1" bandwidth="133334" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <BaseURL>bear-640x360-audio.mp4</BaseURL>
         <SegmentBase indexRange="797-864" timescale="44100">
@@ -25,5 +19,11 @@
         </SegmentBase>
       </Representation>
     </AdaptationSet>
+    <AdaptationSet id="2" contentType="text" subsegmentAlignment="true">
+      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
+      <Representation id="2" bandwidth="273" mimeType="text/vtt">
+        <BaseURL>bear-english-text.vtt</BaseURL>
+      </Representation>
+    </AdaptationSet>
   </Period>
 </MPD>
diff --git a/packager/app/test/testdata/vtt-text-to-mp4-with-ad-cues/output.mpd b/packager/app/test/testdata/vtt-text-to-mp4-with-ad-cues/output.mpd
index 6e663cde8b..0f9f7cc45f 100644
--- a/packager/app/test/testdata/vtt-text-to-mp4-with-ad-cues/output.mpd
+++ b/packager/app/test/testdata/vtt-text-to-mp4-with-ad-cues/output.mpd
@@ -2,19 +2,8 @@
 <!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
 <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-live:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.7360668182373047S">
   <Period id="0" duration="PT2.002S">
-    <AdaptationSet id="0" contentType="text" segmentAlignment="true">
-      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
-      <Representation id="0" bandwidth="1944" codecs="wvtt" mimeType="application/mp4">
-        <SegmentTemplate timescale="1000" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="1">
-          <SegmentTimeline>
-            <S t="0" d="1000" r="1"/>
-            <S t="2000" d="1"/>
-          </SegmentTimeline>
-        </SegmentTemplate>
-      </Representation>
-    </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" width="640" height="360" frameRate="30000/1001" segmentAlignment="true" par="16:9">
-      <Representation id="1" bandwidth="974154" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" segmentAlignment="true" par="16:9">
+      <Representation id="0" bandwidth="974154" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
         <SegmentTemplate timescale="30000" initialization="bear-640x360-video-init.mp4" media="bear-640x360-video-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
             <S t="0" d="30030" r="1"/>
@@ -22,8 +11,8 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="2" contentType="audio" segmentAlignment="true">
-      <Representation id="2" bandwidth="133961" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+    <AdaptationSet id="1" contentType="audio" segmentAlignment="true">
+      <Representation id="1" bandwidth="133961" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <SegmentTemplate timescale="44100" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
@@ -33,20 +22,21 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
-  </Period>
-  <Period id="1" duration="PT.7340666666666671S">
-    <AdaptationSet id="0" contentType="text" segmentAlignment="true">
+    <AdaptationSet id="2" contentType="text" segmentAlignment="true">
       <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
-      <Representation id="0" bandwidth="2056" codecs="wvtt" mimeType="application/mp4">
-        <SegmentTemplate timescale="1000" presentationTimeOffset="2001" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="4">
+      <Representation id="2" bandwidth="1944" codecs="wvtt" mimeType="application/mp4">
+        <SegmentTemplate timescale="1000" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="1">
           <SegmentTimeline>
-            <S t="2001" d="1000" r="2"/>
+            <S t="0" d="1000" r="1"/>
+            <S t="2000" d="1"/>
           </SegmentTimeline>
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="1" contentType="video" width="640" height="360" frameRate="30000/1001" segmentAlignment="true" par="16:9">
-      <Representation id="1" bandwidth="869088" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
+  </Period>
+  <Period id="1" duration="PT.7340666666666671S">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" segmentAlignment="true" par="16:9">
+      <Representation id="0" bandwidth="869088" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
         <SegmentTemplate timescale="30000" presentationTimeOffset="60059" initialization="bear-640x360-video-init.mp4" media="bear-640x360-video-$Number$.m4s" startNumber="3">
           <SegmentTimeline>
             <S t="60060" d="22022"/>
@@ -54,8 +44,8 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
-    <AdaptationSet id="2" contentType="audio" segmentAlignment="true">
-      <Representation id="2" bandwidth="108129" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+    <AdaptationSet id="1" contentType="audio" segmentAlignment="true">
+      <Representation id="1" bandwidth="108129" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
         <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
         <SegmentTemplate timescale="44100" presentationTimeOffset="88288" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="3">
           <SegmentTimeline>
@@ -64,5 +54,15 @@
         </SegmentTemplate>
       </Representation>
     </AdaptationSet>
+    <AdaptationSet id="2" contentType="text" segmentAlignment="true">
+      <Role schemeIdUri="urn:mpeg:dash:role:2011" value="subtitle"/>
+      <Representation id="2" bandwidth="2056" codecs="wvtt" mimeType="application/mp4">
+        <SegmentTemplate timescale="1000" presentationTimeOffset="2001" initialization="bear-english-text-init.mp4" media="bear-english-text-$Number$.m4s" startNumber="4">
+          <SegmentTimeline>
+            <S t="2001" d="1000" r="2"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
+    </AdaptationSet>
   </Period>
 </MPD>
diff --git a/packager/packager.cc b/packager/packager.cc
index 8d66640b97..43e0a0de71 100644
--- a/packager/packager.cc
+++ b/packager/packager.cc
@@ -12,6 +12,7 @@
 #include "packager/app/libcrypto_threading.h"
 #include "packager/app/muxer_factory.h"
 #include "packager/app/packager_util.h"
+#include "packager/app/single_thread_job_manager.h"
 #include "packager/app/stream_descriptor.h"
 #include "packager/base/at_exit.h"
 #include "packager/base/files/file_path.h"
@@ -56,6 +57,7 @@ using media::Demuxer;
 using media::JobManager;
 using media::KeySource;
 using media::MuxerOptions;
+using media::SingleThreadJobManager;
 using media::SyncPointQueue;
 
 namespace media {
@@ -837,7 +839,12 @@ Status Packager::Initialize(
     sync_points.reset(
         new SyncPointQueue(packaging_params.ad_cue_generator_params));
   }
-  internal->job_manager.reset(new JobManager(std::move(sync_points)));
+  if (packaging_params.single_threaded) {
+    internal->job_manager.reset(
+        new SingleThreadJobManager(std::move(sync_points)));
+  } else {
+    internal->job_manager.reset(new JobManager(std::move(sync_points)));
+  }
 
   std::vector<StreamDescriptor> streams_for_jobs;
 
diff --git a/packager/packager.gyp b/packager/packager.gyp
index 1ca81fa6bf..f3b20bf8fa 100644
--- a/packager/packager.gyp
+++ b/packager/packager.gyp
@@ -22,6 +22,8 @@
         'app/libcrypto_threading.h',
         'app/packager_util.cc',
         'app/packager_util.h',
+        'app/single_thread_job_manager.cc',
+        'app/single_thread_job_manager.h',
         'packager.cc',
         'packager.h',
       ],
diff --git a/packager/packager.h b/packager/packager.h
index 19d041ebd9..f4a9a6f502 100644
--- a/packager/packager.h
+++ b/packager/packager.h
@@ -53,6 +53,9 @@ struct PackagingParams {
   /// Create a human readable format of MediaInfo. The output file name will be
   /// the name specified by output flag, suffixed with `.media_info`.
   bool output_media_info = false;
+  /// Only use a single thread to generate output.  This is useful in tests to
+  /// avoid non-deterministic outputs.
+  bool single_threaded = false;
   /// DASH MPD related parameters.
   MpdParams mpd_params;
   /// HLS related parameters.