Merge "Trace Redaction - Remove Timeline Optimizations" into main

13 files changed, 29 insertions, 352 deletions

diff --git a/Android.bp b/Android.bp
index c43694efc..60c862c9f 100644
--- a/Android.bp
+++ b/Android.bp
@@ -13468,7 +13468,6 @@ filegroup {
         "src/trace_redaction/filter_task_rename.cc",
         "src/trace_redaction/find_package_uid.cc",
         "src/trace_redaction/modify_process_trees.cc",
-        "src/trace_redaction/optimize_timeline.cc",
         "src/trace_redaction/populate_allow_lists.cc",
         "src/trace_redaction/process_thread_timeline.cc",
         "src/trace_redaction/proto_util.cc",
diff --git a/src/trace_redaction/BUILD.gn b/src/trace_redaction/BUILD.gn
index 29c4a75e0..45d3bdc87 100644
--- a/src/trace_redaction/BUILD.gn
+++ b/src/trace_redaction/BUILD.gn
@@ -49,8 +49,6 @@ source_set("trace_redaction") {
     "frame_cookie.h",
     "modify_process_trees.cc",
     "modify_process_trees.h",
-    "optimize_timeline.cc",
-    "optimize_timeline.h",
     "populate_allow_lists.cc",
     "populate_allow_lists.h",
     "process_thread_timeline.cc",
diff --git a/src/trace_redaction/filter_sched_waking_events_integrationtest.cc b/src/trace_redaction/filter_sched_waking_events_integrationtest.cc
index d86bf748a..2993ac0a5 100644
--- a/src/trace_redaction/filter_sched_waking_events_integrationtest.cc
+++ b/src/trace_redaction/filter_sched_waking_events_integrationtest.cc
@@ -24,7 +24,6 @@
 #include "src/trace_redaction/collect_timeline_events.h"
 #include "src/trace_redaction/filter_sched_waking_events.h"
 #include "src/trace_redaction/find_package_uid.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/scrub_ftrace_events.h"
 #include "src/trace_redaction/trace_redaction_framework.h"
 #include "src/trace_redaction/trace_redaction_integration_fixture.h"
@@ -50,7 +49,6 @@ class RedactSchedWakingIntegrationTest
   void SetUp() override {
     trace_redactor()->emplace_collect<FindPackageUid>();
     trace_redactor()->emplace_collect<CollectTimelineEvents>();
-    trace_redactor()->emplace_build<OptimizeTimeline>();
 
     auto* ftrace_filter =
         trace_redactor()->emplace_transform<ScrubFtraceEvents>();
diff --git a/src/trace_redaction/filter_task_rename_integrationtest.cc b/src/trace_redaction/filter_task_rename_integrationtest.cc
index 14c66dd17..f080fe7e0 100644
--- a/src/trace_redaction/filter_task_rename_integrationtest.cc
+++ b/src/trace_redaction/filter_task_rename_integrationtest.cc
@@ -24,7 +24,6 @@
 #include "src/trace_redaction/collect_timeline_events.h"
 #include "src/trace_redaction/filter_task_rename.h"
 #include "src/trace_redaction/find_package_uid.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/trace_redaction_framework.h"
 #include "src/trace_redaction/trace_redaction_integration_fixture.h"
 #include "src/trace_redaction/trace_redactor.h"
@@ -57,7 +56,6 @@ class RenameEventsTraceRedactorIntegrationTest
     // registered primitives are there to generate the timeline.
     trace_redactor()->emplace_collect<FindPackageUid>();
     trace_redactor()->emplace_collect<CollectTimelineEvents>();
-    trace_redactor()->emplace_build<OptimizeTimeline>();
 
     auto scrub_ftrace_events =
         trace_redactor()->emplace_transform<ScrubFtraceEvents>();
diff --git a/src/trace_redaction/main.cc b/src/trace_redaction/main.cc
index 051a424ac..eec75fd6b 100644
--- a/src/trace_redaction/main.cc
+++ b/src/trace_redaction/main.cc
@@ -25,7 +25,6 @@
 #include "src/trace_redaction/filter_sched_waking_events.h"
 #include "src/trace_redaction/filter_task_rename.h"
 #include "src/trace_redaction/find_package_uid.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/populate_allow_lists.h"
 #include "src/trace_redaction/prune_package_list.h"
 #include "src/trace_redaction/redact_ftrace_event.h"
@@ -58,7 +57,6 @@ static base::Status Main(std::string_view input,
   // Add all builders.
   redactor.emplace_build<PopulateAllowlists>();
   redactor.emplace_build<AllowSuspendResume>();
-  redactor.emplace_build<OptimizeTimeline>();
   redactor.emplace_build<ReduceFrameCookies>();
   redactor.emplace_build<BuildSyntheticThreads>();
 
diff --git a/src/trace_redaction/optimize_timeline.cc b/src/trace_redaction/optimize_timeline.cc
deleted file mode 100644
index 713f7c71f..000000000
--- a/src/trace_redaction/optimize_timeline.cc
+++ /dev/null
@@ -1,54 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * 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.
- */
-
-#include "src/trace_redaction/optimize_timeline.h"
-
-#include "perfetto/base/status.h"
-#include "src/trace_redaction/trace_redaction_framework.h"
-
-namespace perfetto::trace_redaction {
-
-base::Status OptimizeTimeline::Build(Context* context) const {
-  if (!context->timeline) {
-    return base::ErrStatus(
-        "Cannot optimize a null timeline. Are you missing "
-        "CollectTimelineEvents or an "
-        "alternative?");
-  }
-
-  if (!context->package_uid.has_value()) {
-    return base::ErrStatus(
-        "Missing package uid. Are you missing FindPackageUid or an "
-        "alternative?");
-  }
-
-  auto* timeline = context->timeline.get();
-
-  // Change the timeline from read-only to write only mode.
-  timeline->Sort();
-
-  // Goes over the whole timeline, reducing the distance between a pid and its
-  // uid.
-  timeline->Flatten();
-
-  // Reduce the number of events. This makes the timeline specific to the
-  // package uid (i.e. either 0 or package_uid will be returned).
-  timeline->Reduce(*context->package_uid);
-
-  return base::OkStatus();
-}
-
-}  // namespace perfetto::trace_redaction
diff --git a/src/trace_redaction/optimize_timeline.h b/src/trace_redaction/optimize_timeline.h
deleted file mode 100644
index e14285170..000000000
--- a/src/trace_redaction/optimize_timeline.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * 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.
- */
-
-#ifndef SRC_TRACE_REDACTION_OPTIMIZE_TIMELINE_H_
-#define SRC_TRACE_REDACTION_OPTIMIZE_TIMELINE_H_
-
-#include "perfetto/base/status.h"
-#include "src/trace_redaction/trace_redaction_framework.h"
-
-namespace perfetto::trace_redaction {
-
-// Converts a timeline from a write-only structure to a read-only structure.
-class OptimizeTimeline : public BuildPrimitive {
- public:
-  base::Status Build(Context* context) const override;
-};
-
-}  // namespace perfetto::trace_redaction
-
-#endif  // SRC_TRACE_REDACTION_OPTIMIZE_TIMELINE_H_
diff --git a/src/trace_redaction/process_thread_timeline.cc b/src/trace_redaction/process_thread_timeline.cc
index 7bd4ea494..a678d99d3 100644
--- a/src/trace_redaction/process_thread_timeline.cc
+++ b/src/trace_redaction/process_thread_timeline.cc
@@ -20,6 +20,7 @@
 #include <cstddef>
 #include <cstdint>
 #include <optional>
+#include "perfetto/base/logging.h"
 
 namespace perfetto::trace_redaction {
 namespace {
@@ -35,57 +36,19 @@ bool OrderByPid(const ProcessThreadTimeline::Event& left,
 }  // namespace
 
 void ProcessThreadTimeline::Append(const Event& event) {
-  write_only_events_.push_back(event);
+  events_.push_back(event);
+  mode_ = Mode::kWrite;
 }
 
 void ProcessThreadTimeline::Sort() {
-  write_only_events_.sort(OrderByPid);
-
-  // Copy all events that don't match adjacent events. This should reduce the
-  // number of events because process trees may contain the same data
-  // back-to-back.
-  read_only_events_.reserve(write_only_events_.size());
-
-  for (auto event : write_only_events_) {
-    if (read_only_events_.empty() || event != read_only_events_.back()) {
-      read_only_events_.push_back(event);
-    }
-  }
-
-  // Events have been moved from the write-only list to the read-only vector.
-  // The resources backing the write-only list can be release.
-  write_only_events_.clear();
-}
-
-void ProcessThreadTimeline::Flatten() {
-  // Union-find-like action to collapse the tree.
-  for (auto& event : read_only_events_) {
-    if (event.type() != Event::Type::kOpen) {
-      continue;
-    }
-
-    auto event_with_package = Search(0, event.ts(), event.pid());
-
-    if (event_with_package.has_value()) {
-      event = Event::Open(event.ts(), event.pid(), event.ppid(),
-                          event_with_package->uid());
-    }
-  }
-}
-
-void ProcessThreadTimeline::Reduce(uint64_t package_uid) {
-  auto remove_open_events = [package_uid](const Event& event) {
-    return event.uid() != package_uid && event.type() == Event::Type::kOpen;
-  };
-
-  read_only_events_.erase(
-      std::remove_if(read_only_events_.begin(), read_only_events_.end(),
-                     remove_open_events),
-      read_only_events_.end());
+  std::sort(events_.begin(), events_.end(), OrderByPid);
+  mode_ = Mode::kRead;
 }
 
 ProcessThreadTimeline::Slice ProcessThreadTimeline::Search(uint64_t ts,
                                                            int32_t pid) const {
+  PERFETTO_CHECK(mode_ == Mode::kRead);
+
   Slice s;
   s.pid = pid;
   s.uid = 0;
@@ -100,6 +63,8 @@ ProcessThreadTimeline::Slice ProcessThreadTimeline::Search(uint64_t ts,
 
 std::optional<ProcessThreadTimeline::Event>
 ProcessThreadTimeline::Search(size_t depth, uint64_t ts, int32_t pid) const {
+  PERFETTO_DCHECK(mode_ == Mode::kRead);
+
   if (depth >= kMaxSearchDepth) {
     return std::nullopt;
   }
@@ -117,33 +82,10 @@ ProcessThreadTimeline::Search(size_t depth, uint64_t ts, int32_t pid) const {
   return Search(depth + 1, ts, event->ppid());
 }
 
-std::optional<size_t> ProcessThreadTimeline::GetDepth(uint64_t ts,
-                                                      int32_t pid) const {
-  return GetDepth(0, ts, pid);
-}
-
-std::optional<size_t> ProcessThreadTimeline::GetDepth(size_t depth,
-                                                      uint64_t ts,
-                                                      int32_t pid) const {
-  if (depth >= kMaxSearchDepth) {
-    return std::nullopt;
-  }
-
-  auto event = FindPreviousEvent(ts, pid);
-
-  if (!TestEvent(event)) {
-    return std::nullopt;
-  }
-
-  if (event->uid() != 0) {
-    return depth;
-  }
-
-  return GetDepth(depth + 1, ts, event->ppid());
-}
-
 std::optional<ProcessThreadTimeline::Event>
 ProcessThreadTimeline::FindPreviousEvent(uint64_t ts, int32_t pid) const {
+  PERFETTO_DCHECK(mode_ == Mode::kRead);
+
   Event fake = Event::Close(ts, pid);
 
   // Events are in ts-order within each pid-group. See Optimize(), Because each
@@ -152,11 +94,10 @@ ProcessThreadTimeline::FindPreviousEvent(uint64_t ts, int32_t pid) const {
   //
   // Find the first process event. Then perform a linear search. There won't be
   // many events per process.
-  auto at = std::lower_bound(read_only_events_.begin(), read_only_events_.end(),
-                             fake, OrderByPid);
+  auto at = std::lower_bound(events_.begin(), events_.end(), fake, OrderByPid);
 
-  // `pid` was not found in `read_only_events_`.
-  if (at == read_only_events_.end()) {
+  // `pid` was not found in `events_`.
+  if (at == events_.end()) {
     return std::nullopt;
   }
 
@@ -173,7 +114,7 @@ ProcessThreadTimeline::FindPreviousEvent(uint64_t ts, int32_t pid) const {
   //
   // 3. The performance gains are minimal or non-existant because of the small
   //    number of events.
-  for (; at != read_only_events_.end() && at->pid() == pid; ++at) {
+  for (; at != events_.end() && at->pid() == pid; ++at) {
     if (at->ts() > ts) {
       continue;  // Ignore events in the future.
     }
diff --git a/src/trace_redaction/process_thread_timeline.h b/src/trace_redaction/process_thread_timeline.h
index 3a6f6ac87..4e1354c25 100644
--- a/src/trace_redaction/process_thread_timeline.h
+++ b/src/trace_redaction/process_thread_timeline.h
@@ -18,7 +18,6 @@
 #define SRC_TRACE_REDACTION_PROCESS_THREAD_TIMELINE_H_
 
 #include <cstdint>
-#include <list>
 #include <optional>
 #include <vector>
 
@@ -121,22 +120,6 @@ class ProcessThreadTimeline {
   // subset of events will, on average, be trivally small.
   void Sort();
 
-  // OPTIONAL: minimizes the distance between the leaf nodes and the package
-  // nodes (a node with a uid value not equal to zero).
-  void Flatten();
-
-  // OPTIONAL: Removes events from the timeline that:
-  //
-  //  1. Reduces the number of events in the timeline to shrink the search
-  //  space.
-  //
-  //  2. Does not invalidate the timeline.
-  //
-  // This can only be called after calling Sort(). Calling Reduce() before
-  // Sort() has undefined behaviour. Calling Reduce() after AppendOpen() if
-  // AppendClose() (without a call to Sort() call) has undefined behaviour.
-  void Reduce(uint64_t package_uid);
-
   // Returns a snapshot that contains a process's pid and ppid, but contains the
   // first uid found in its parent-child chain. If a uid cannot be found, uid=0
   // is returned.
@@ -144,27 +127,18 @@ class ProcessThreadTimeline {
   // `Sort()` must be called before this.
   Slice Search(uint64_t ts, int32_t pid) const;
 
-  // Finds the distance between pid and its uid.
-  //
-  // Returns -1 it pid has no connection to a uid.
-  // Returns 0 if pid has an immediately connection to a uid.
-  //
-  // Return n where:  n is the number of pids between the given pid and the pid
-  //                  connected to the uid. For example, assume D() is a
-  //                  function that measures the distance between two nodes in
-  //                  the same chain:
-  //
-  //                    | pid | depth
-  //                    | a   : 0
-  //                    | b   : 1
-  //                    | c   : 2 --> uid = 98
-  //
-  //                    D(a) = 2
-  //                    D(b) = 1
-  //                    D(c) = 0
-  std::optional<size_t> GetDepth(uint64_t ts, int32_t pid) const;
-
  private:
+  enum class Mode {
+    // The timeline can safely be queried. If the timeline is in read mode, and
+    // a user writes to the timeline, the timeline will change to write mode.
+    kRead,
+
+    // The timeline change be changed. If the timeline is not in write mode,
+    // reading from the timeline will throw an error. Sort() must be called to
+    // change the timeline from write to read mode.
+    kWrite
+  };
+
   // Effectively this is the same as:
   //
   //  events_for(pid).before(ts).sort_by_time().last()
@@ -172,14 +146,11 @@ class ProcessThreadTimeline {
 
   std::optional<Event> Search(size_t depth, uint64_t ts, int32_t pid) const;
 
-  std::optional<size_t> GetDepth(size_t depth, uint64_t ts, int32_t pid) const;
-
   bool TestEvent(std::optional<Event> event) const;
 
-  // The number of events are unclear. Use a list when in "write-only" mode and
-  // then change to a vector for "read-only" mode.
-  std::list<Event> write_only_events_;
-  std::vector<Event> read_only_events_;
+  std::vector<Event> events_;
+
+  Mode mode_ = Mode::kRead;
 };
 
 }  // namespace perfetto::trace_redaction
diff --git a/src/trace_redaction/process_thread_timeline_unittest.cc b/src/trace_redaction/process_thread_timeline_unittest.cc
index ea7e5e5e5..daca1f18c 100644
--- a/src/trace_redaction/process_thread_timeline_unittest.cc
+++ b/src/trace_redaction/process_thread_timeline_unittest.cc
@@ -38,26 +38,6 @@ class SliceTestParams {
   uint64_t uid_;
 };
 
-class DepthTestParams {
- public:
-  DepthTestParams(uint64_t ts,
-                  int32_t pid,
-                  std::optional<size_t> raw_depth,
-                  std::optional<size_t> flat_depth)
-      : ts_(ts), pid_(pid), raw_depth_(raw_depth), flat_depth_(flat_depth) {}
-
-  uint64_t ts() const { return ts_; }
-  int32_t pid() const { return pid_; }
-  std::optional<size_t> raw_depth() const { return raw_depth_; }
-  std::optional<size_t> flat_depth() const { return flat_depth_; }
-
- private:
-  uint64_t ts_;
-  int32_t pid_;
-  std::optional<size_t> raw_depth_;
-  std::optional<size_t> flat_depth_;
-};
-
 constexpr uint64_t kTimeA = 0;
 constexpr uint64_t kTimeB = 10;
 constexpr uint64_t kTimeC = 20;
@@ -65,12 +45,9 @@ constexpr uint64_t kTimeD = 30;
 constexpr uint64_t kTimeE = 40;
 constexpr uint64_t kTimeF = 50;
 constexpr uint64_t kTimeG = 60;
-constexpr uint64_t kTimeH = 70;
-constexpr uint64_t kTimeI = 70;
 
 constexpr int32_t kPidA = 1;
 constexpr int32_t kPidB = 2;
-constexpr int32_t kPidC = 3;
 
 constexpr uint64_t kNoPackage = 0;
 
@@ -95,7 +72,6 @@ TEST_P(TimelineEventsOpenAndCloseSingleTest, PidsEndOnClose) {
   timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeD, kPidB));
 
   timeline_.Sort();
-  timeline_.Flatten();
 
   auto slice = timeline_.Search(params.ts(), params.pid());
   ASSERT_EQ(slice.pid, params.pid());
@@ -224,102 +200,4 @@ INSTANTIATE_TEST_SUITE_P(
                     SliceTestParams(kTimeD, kPidB, kUidA),
                     SliceTestParams(kTimeE, kPidB, kNoPackage)));
 
-class TimelineEventsFlattenTest
-    : public testing::Test,
-      public testing::WithParamInterface<DepthTestParams> {
- protected:
-  ProcessThreadTimeline timeline_;
-};
-
-TEST_P(TimelineEventsFlattenTest, BeforeFlatten) {
-  auto params = GetParam();
-
-  // |---------- PID_A ----------|
-  //      |----- PID_B -----|
-  //         |-- PID_C --|
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeB, kPidA, 0, kUidA));
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeC, kPidB, kPidA));
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeD, kPidC, kPidB));
-
-  // Time E is when all spans are valid.
-
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeF, kPidC));
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeG, kPidB));
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeH, kPidA));
-
-  timeline_.Sort();
-
-  auto depth = timeline_.GetDepth(params.ts(), params.pid());
-  ASSERT_EQ(depth, params.raw_depth());
-}
-
-TEST_P(TimelineEventsFlattenTest, AfterFlatten) {
-  auto params = GetParam();
-
-  // |---------- PID_A ----------|
-  //      |----- PID_B -----|
-  //         |-- PID_C --|
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeB, kPidA, 0, kUidA));
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeC, kPidB, kPidA));
-  timeline_.Append(ProcessThreadTimeline::Event::Open(kTimeD, kPidC, kPidB));
-
-  // Time E is when all spans are valid.
-
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeF, kPidC));
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeG, kPidB));
-  timeline_.Append(ProcessThreadTimeline::Event::Close(kTimeH, kPidA));
-
-  timeline_.Sort();
-  timeline_.Flatten();
-
-  auto depth = timeline_.GetDepth(params.ts(), params.pid());
-  ASSERT_EQ(depth, params.flat_depth());
-}
-
-INSTANTIATE_TEST_SUITE_P(
-    AcrossWholeTimeline,
-    TimelineEventsFlattenTest,
-    testing::Values(
-        // Pid A
-        DepthTestParams(kTimeA, kPidA, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeB, kPidA, 0, 0),
-        DepthTestParams(kTimeC, kPidA, 0, 0),
-        DepthTestParams(kTimeD, kPidA, 0, 0),
-        DepthTestParams(kTimeE, kPidA, 0, 0),
-        DepthTestParams(kTimeF, kPidA, 0, 0),
-        DepthTestParams(kTimeG, kPidA, 0, 0),
-        DepthTestParams(kTimeH,
-                        kPidA,
-                        std::nullopt,
-                        std::nullopt),  // pid A ends
-        DepthTestParams(kTimeI, kPidA, std::nullopt, std::nullopt),
-
-        // Pid B
-        DepthTestParams(kTimeA, kPidB, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeB, kPidB, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeC, kPidB, 1, 0),
-        DepthTestParams(kTimeD, kPidB, 1, 0),
-        DepthTestParams(kTimeE, kPidB, 1, 0),
-        DepthTestParams(kTimeF, kPidB, 1, 0),
-        DepthTestParams(kTimeG,
-                        kPidB,
-                        std::nullopt,
-                        std::nullopt),  // pid B ends
-        DepthTestParams(kTimeH, kPidB, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeI, kPidB, std::nullopt, std::nullopt),
-
-        // Pid C
-        DepthTestParams(kTimeA, kPidC, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeB, kPidC, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeC, kPidC, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeD, kPidC, 2, 0),
-        DepthTestParams(kTimeE, kPidC, 2, 0),
-        DepthTestParams(kTimeF,
-                        kPidC,
-                        std::nullopt,
-                        std::nullopt),  // pid C ends
-        DepthTestParams(kTimeG, kPidC, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeH, kPidC, std::nullopt, std::nullopt),
-        DepthTestParams(kTimeI, kPidC, std::nullopt, std::nullopt)));
-
 }  // namespace perfetto::trace_redaction
diff --git a/src/trace_redaction/redact_sched_switch_integrationtest.cc b/src/trace_redaction/redact_sched_switch_integrationtest.cc
index 85d7416a7..f14d6e990 100644
--- a/src/trace_redaction/redact_sched_switch_integrationtest.cc
+++ b/src/trace_redaction/redact_sched_switch_integrationtest.cc
@@ -22,7 +22,6 @@
 #include "src/base/test/status_matchers.h"
 #include "src/trace_redaction/collect_timeline_events.h"
 #include "src/trace_redaction/find_package_uid.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/redact_sched_switch.h"
 #include "src/trace_redaction/trace_redaction_framework.h"
 #include "src/trace_redaction/trace_redaction_integration_fixture.h"
@@ -44,7 +43,6 @@ class RedactSchedSwitchIntegrationTest
   void SetUp() override {
     trace_redactor()->emplace_collect<FindPackageUid>();
     trace_redactor()->emplace_collect<CollectTimelineEvents>();
-    trace_redactor()->emplace_build<OptimizeTimeline>();
 
     auto* ftrace_event_redactions =
         trace_redactor()->emplace_transform<RedactFtraceEvent>();
diff --git a/src/trace_redaction/scrub_process_stats_integrationtest.cc b/src/trace_redaction/scrub_process_stats_integrationtest.cc
index 2b081e527..cce2b6b38 100644
--- a/src/trace_redaction/scrub_process_stats_integrationtest.cc
+++ b/src/trace_redaction/scrub_process_stats_integrationtest.cc
@@ -20,7 +20,6 @@
 #include "perfetto/base/status.h"
 #include "src/base/test/status_matchers.h"
 #include "src/trace_redaction/collect_timeline_events.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/scrub_process_stats.h"
 #include "src/trace_redaction/trace_redaction_framework.h"
 #include "src/trace_redaction/trace_redaction_integration_fixture.h"
@@ -38,7 +37,6 @@ class ScrubProcessStatsTest : public testing::Test,
  protected:
   void SetUp() override {
     trace_redactor()->emplace_collect<CollectTimelineEvents>();
-    trace_redactor()->emplace_build<OptimizeTimeline>();
     trace_redactor()->emplace_transform<ScrubProcessStats>();
 
     // Package "com.Unity.com.unity.multiplayer.samples.coop";
diff --git a/src/trace_redaction/scrub_process_trees_integrationtest.cc b/src/trace_redaction/scrub_process_trees_integrationtest.cc
index 58396b2b9..a001a36cf 100644
--- a/src/trace_redaction/scrub_process_trees_integrationtest.cc
+++ b/src/trace_redaction/scrub_process_trees_integrationtest.cc
@@ -21,7 +21,6 @@
 #include "src/base/test/status_matchers.h"
 #include "src/trace_redaction/collect_timeline_events.h"
 #include "src/trace_redaction/find_package_uid.h"
-#include "src/trace_redaction/optimize_timeline.h"
 #include "src/trace_redaction/scrub_process_trees.h"
 #include "src/trace_redaction/trace_redaction_framework.h"
 #include "src/trace_redaction/trace_redaction_integration_fixture.h"
@@ -45,20 +44,8 @@ class ScrubProcessTreesIntegrationTest
       protected TraceRedactionIntegrationFixure {
  protected:
   void SetUp() override {
-    // ScrubProcessTrees depends on:
-    //    - FindPackageUid    (creates: uid)
-    //    - OptimizeTimeline  (creates: optimized timeline)
-    //
-    // OptimizeTimeline depends on:
-    //    - FindPackageUid (uses: uid)
-    //    - CollectTimelineEvents  (uses: timeline)
-    //
-    // CollectTimelineEvents depends on.... nothing
-    // FindPackageUid depends on... nothing
-
     trace_redactor()->emplace_collect<FindPackageUid>();
     trace_redactor()->emplace_collect<CollectTimelineEvents>();
-    trace_redactor()->emplace_build<OptimizeTimeline>();
     trace_redactor()->emplace_transform<ScrubProcessTrees>();
 
     // In this case, the process and package have the same name.