From 86fdeab739f80f37fde9acd31f2808fd3959568a Mon Sep 17 00:00:00 2001
From: Martin Kustermann <kustermann@google.com>
Date: Tue, 10 Nov 2020 18:41:24 +0000
Subject: [PATCH] [vm] Remove unused --print-benchmarking-metrics flag

This flag doesn't seem to be used anywhere, neither of
dart/flutter/golem/g3.

Main motivation is to remove the GC triggering code in
Isolate::MakeRunnable.

Issue https://github.com/dart-lang/sdk/issues/36097

Change-Id: If48072f62974dec5f7c19cc08be7904401e38a61
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/171282
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
---
 runtime/vm/flag_list.h |  2 --
 runtime/vm/isolate.cc  | 11 +----------
 runtime/vm/metrics.cc  |  2 +-
 3 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/runtime/vm/flag_list.h b/runtime/vm/flag_list.h
index 5e022399315..341b4fc3ce8 100644
--- a/runtime/vm/flag_list.h
+++ b/runtime/vm/flag_list.h
@@ -167,8 +167,6 @@ constexpr bool kDartUseBackgroundCompilation = true;
   P(print_snapshot_sizes, bool, false, "Print sizes of generated snapshots.")  \
   P(print_snapshot_sizes_verbose, bool, false,                                 \
     "Print cluster sizes of generated snapshots.")                             \
-  P(print_benchmarking_metrics, bool, false,                                   \
-    "Print additional memory and latency metrics for benchmarking.")           \
   R(print_ssa_liveranges, false, bool, false,                                  \
     "Print live ranges after allocation.")                                     \
   R(print_stacktrace_at_api_error, false, bool, false,                         \
diff --git a/runtime/vm/isolate.cc b/runtime/vm/isolate.cc
index b7357769443..11991c00d28 100644
--- a/runtime/vm/isolate.cc
+++ b/runtime/vm/isolate.cc
@@ -2091,15 +2091,6 @@ const char* Isolate::MakeRunnable() {
     Service::HandleEvent(&runnableEvent);
   }
   GetRunnableLatencyMetric()->set_value(UptimeMicros());
-  if (FLAG_print_benchmarking_metrics) {
-    {
-      StartIsolateScope scope(this);
-      heap()->CollectAllGarbage();
-    }
-    int64_t heap_size = (heap()->UsedInWords(Heap::kNew) * kWordSize) +
-                        (heap()->UsedInWords(Heap::kOld) * kWordSize);
-    GetRunnableHeapSizeMetric()->set_value(heap_size);
-  }
 #endif  // !PRODUCT
   return nullptr;
 }
@@ -2553,7 +2544,7 @@ void Isolate::LowLevelShutdown() {
         "\tisolate:    %s\n",
         name());
   }
-  if (FLAG_print_metrics || FLAG_print_benchmarking_metrics) {
+  if (FLAG_print_metrics) {
     LogBlock lb;
     OS::PrintErr("Printing metrics for %s\n", name());
 #define ISOLATE_GROUP_METRIC_PRINT(type, variable, name, unit)                 \
diff --git a/runtime/vm/metrics.cc b/runtime/vm/metrics.cc
index ecfda6c6d53..f7e582b90b3 100644
--- a/runtime/vm/metrics.cc
+++ b/runtime/vm/metrics.cc
@@ -206,7 +206,7 @@ void Metric::Init() {
 }
 
 void Metric::Cleanup() {
-  if (FLAG_print_metrics || FLAG_print_benchmarking_metrics) {
+  if (FLAG_print_metrics) {
     // Create a zone to allocate temporary strings in.
     StackZone sz(Thread::Current());
     OS::PrintErr("Printing metrics for VM\n");