Simplify profiling and benchmarks.

- Tweak the benchmarks to work with b.N where appropriate. In many cases,
  b.N was simply being ignored. This creates an implicit dependency in the
  user passing a reasonable benchtime (less than or equal to the actual
  runtime of the test, or using the X syntax) otherwise the test runs
  forever.
- In cases where the above is impossible, explicitly set benchtime from
  the test wrapper, to prevent the above behavior (tensorflow).
- Drop the *Reverse variants, which are simply hey benchmarks. We should
  just add a hey benchmark. The platforms benchmarks already include a
  native platform, and thus these benchmarks are incredibly confusing.
  (In other words, BenchmarkNginxReverse has nothing to do with an nginx
  benchmark for runsc.)
- Remove the redunant Harness object, which contains no state, in order
  to slightly simplify the code.
- Make Block and Heap profiling actually work, but setting appropriate
  runtime parameters (and plumbing them through the config).
- Split the profiling into two phases: start and stop, since some will
  need to be started early, and others will need to happen at the end.

PiperOrigin-RevId: 349495377

1 files changed, 6 insertions, 6 deletions

diff --git a/test/benchmarks/media/ffmpeg_test.go b/test/benchmarks/media/ffmpeg_test.go
index a462ec2a6..1b99a319a 100644
--- a/test/benchmarks/media/ffmpeg_test.go
+++ b/test/benchmarks/media/ffmpeg_test.go
@@ -23,12 +23,10 @@ import (
 	"gvisor.dev/gvisor/test/benchmarks/harness"
 )
 
-var h harness.Harness
-
 // BenchmarkFfmpeg runs ffmpeg in a container and records runtime.
 // BenchmarkFfmpeg should run as root to drop caches.
 func BenchmarkFfmpeg(b *testing.B) {
-	machine, err := h.GetMachine()
+	machine, err := harness.GetMachine()
 	if err != nil {
 		b.Fatalf("failed to get machine: %v", err)
 	}
@@ -38,24 +36,26 @@ func BenchmarkFfmpeg(b *testing.B) {
 	cmd := strings.Split("ffmpeg -i video.mp4 -c:v libx264 -preset veryslow output.mp4", " ")
 
 	b.ResetTimer()
+	b.StopTimer()
+
 	for i := 0; i < b.N; i++ {
-		b.StopTimer()
 		container := machine.GetContainer(ctx, b)
 		defer container.CleanUp(ctx)
 		if err := harness.DropCaches(machine); err != nil {
 			b.Skipf("failed to drop caches: %v. You probably need root.", err)
 		}
-		b.StartTimer()
 
+		b.StartTimer()
 		if _, err := container.Run(ctx, dockerutil.RunOpts{
 			Image: "benchmarks/ffmpeg",
 		}, cmd...); err != nil {
 			b.Fatalf("failed to run container: %v", err)
 		}
+		b.StopTimer()
 	}
 }
 
 func TestMain(m *testing.M) {
-	h.Init()
+	harness.Init()
 	os.Exit(m.Run())
 }