[tools/perf] Stop reading pre-calculated histograms

Saving histograms as an artifact in Telemetry and reading them in
Results Processor was a temporary measure to make transition
more smooth. Now it's time to remove it.

Bug: 981349
Change-Id: Ib303177903456e8d81aae9de89c47117c96cd7e1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1900990Reviewed-by: Juan Antonio Navarro Pérez <perezju@chromium.org>
Commit-Queue: Mikhail Khokhlov <khokhlov@google.com>
Cr-Commit-Position: refs/heads/master@{#713422}

tools/perf/core/results_processor/compute_metrics.py

@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import json
 import logging
 import os
 import time
@@ -15,14 +14,6 @@ from tracing.metrics import metric_runner
 # Aggregated trace is saved under this name.
 HTML_TRACE_NAME = 'trace.html'
 
-# Results of metric computation are stored under this key in test_results.
-HISTOGRAM_DICTS_KEY = 'histogram_dicts'
-
-# This file is written by telemetry, it contains output of metric computation.
-# This is a temporary hack to keep things working while we gradually move
-# code from Telemetry to Results Processor.
-HISTOGRAM_DICTS_FILE = 'histogram_dicts.json'
-
 
 def _RunMetric(test_result):
   metrics = [tag['value'] for tag in test_result['tags']
@@ -61,18 +52,9 @@ def ComputeTBMv2Metrics(test_result):
 
   For each test run that has an aggregate trace and some TBMv2 metrics listed
   in its tags, compute the metrics and return the list of all resulting
-  histograms. Note: the order of histograms in the results may be different
-  from the order of tests in intermediate_results.
+  histograms.
   """
   artifacts = test_result.get('outputArtifacts', {})
-  # TODO(crbug.com/981349): If metrics have already been computed in
-  # Telemetry, we read it from the file. Remove this branch after Telemetry
-  # does not compute metrics anymore.
-  if HISTOGRAM_DICTS_FILE in artifacts:
-    with open(artifacts[HISTOGRAM_DICTS_FILE]['filePath']) as f:
-      test_result['_histograms'].ImportDicts(json.load(f))
-    del artifacts[HISTOGRAM_DICTS_FILE]
-    return
 
   if test_result['status'] == 'SKIP':
     return
@@ -85,7 +67,6 @@ def ComputeTBMv2Metrics(test_result):
                        / (2 ** 20))
   # Bails out on traces that are too big. See crbug.com/812631 for more
   # details.
-  # TODO(crbug.com/1010041): Return a non-zero exit code in this case.
   if trace_size_in_mib > 400:
     util.SetUnexpectedFailure(test_result)
     logging.error('%s: Trace size is too big: %s MiB',

tools/perf/core/results_processor/processor.py

@@ -199,11 +199,9 @@ def UploadArtifacts(test_result, upload_bucket, run_identifier):
   for name, artifact in artifacts.iteritems():
     if 'remoteUrl' in artifact:
       continue
-    # TODO(crbug.com/981349): Remove check for HISTOGRAM_DICTS_FILE
-    # after Telemetry does not save histograms as an artifact anymore.
-    # Another TODO(crbug.com/981349): Think of a more general way to
+    # TODO(crbug.com/981349): Think of a more general way to
     # specify which artifacts deserve uploading.
-    if name in [compute_metrics.HISTOGRAM_DICTS_FILE, MEASUREMENTS_NAME]:
+    if name == MEASUREMENTS_NAME:
       continue
     remote_name = '/'.join([run_identifier, test_result['testPath'], name])
     urlsafe_remote_name = re.sub(r'[^A-Za-z0-9/.-]+', '_', remote_name)