sdk/platform-tools/systrace/catapult/telemetry/telemetry/util/bot_utils.py

   1 # Copyright 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 """
   6 Utility functions used to generate info used by the bots.
   7
   8 TODO(eyaich): Remove once we no longer generate the list of benchmarks to
   9 run on the perf waterfall in telemetry.
  10 """
  11
  12 import hashlib
  13
  14 def GetDeviceAffinity(num_shards, base_name):
  15   # Based on the current timings, we shift the result of the hash function to
  16   # achieve better load balancing. Those shift values are to be revised when
  17   # necessary. The shift value is calculated such that the total cycle time
  18   # is minimized.
  19   hash_shift = {
  20     2 : 47,  # for old desktop configurations with 2 slaves
  21     5 : 56,  # for new desktop configurations with 5 slaves
  22     21 : 43  # for Android 3 slaves 7 devices configurations
  23   }
  24   shift = hash_shift.get(num_shards, 0)
  25   base_name_hash = hashlib.sha1(base_name).hexdigest()
  26   device_affinity = (int(base_name_hash, 16) >> shift) % num_shards
  27   return device_affinity