# Copyright 2015 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Module to optimize the scheduling of benchmark_run tasks."""
from __future__ import print_function
import sys
import test_flag
import traceback
from collections import defaultdict
from machine_image_manager import MachineImageManager
from threading import Lock
from threading import Thread
from cros_utils import command_executer
from cros_utils import logger
class DutWorker(Thread):
"""Working thread for a dut."""
def __init__(self, dut, sched):
super(DutWorker, self).__init__(name='DutWorker-{}'.format(dut.name))
self._dut = dut
self._sched = sched
self._stat_num_br_run = 0
self._stat_num_reimage = 0
self._stat_annotation = ''
self._logger = logger.GetLogger(self._sched.get_experiment().log_dir)
self.daemon = True
self._terminated = False
self._active_br = None
# Race condition accessing _active_br between _execute_benchmark_run and
# _terminate, so lock it up.
self._active_br_lock = Lock()
def terminate(self):
self._terminated = True
with self._active_br_lock:
if self._active_br is not None:
# BenchmarkRun.Terminate() terminates any running testcase via
# suite_runner.Terminate and updates timeline.
self._active_br.Terminate()
def run(self):
"""Do the "run-test->(optionally reimage)->run-test" chore.
Note - 'br' below means 'benchmark_run'.
"""
# Firstly, handle benchmarkruns that have cache hit.
br = self._sched.get_cached_benchmark_run()
while br:
try:
self._stat_annotation = 'finishing cached {}'.format(br)
br.run()
except RuntimeError:
traceback.print_exc(file=sys.stdout)
br = self._sched.get_cached_benchmark_run()
# Secondly, handle benchmarkruns that needs to be run on dut.
self._setup_dut_label()
try:
self._logger.LogOutput('{} started.'.format(self))
while not self._terminated:
br = self._sched.get_benchmark_run(self._dut)
if br is None:
# No br left for this label. Considering reimaging.
label = self._sched.allocate_label(self._dut)
if label is None:
# No br even for other labels. We are done.
self._logger.LogOutput('ImageManager found no label '
'for dut, stopping working '
'thread {}.'.format(self))
break
if self._reimage(label):
# Reimage to run other br fails, dut is doomed, stop
# this thread.
self._logger.LogWarning('Re-image failed, dut '
'in an unstable state, stopping '
'working thread {}.'.format(self))
break
else:
# Execute the br.
self._execute_benchmark_run(br)
finally:
self._stat_annotation = 'finished'
# Thread finishes. Notify scheduler that I'm done.
self._sched.dut_worker_finished(self)
def _reimage(self, label):
"""Reimage image to label.
Args:
label: the label to remimage onto dut.
Returns:
0 if successful, otherwise 1.
"""
# Termination could happen anywhere, check it.
if self._terminated:
return 1
self._logger.LogOutput('Reimaging {} using {}'.format(self, label))
self._stat_num_reimage += 1
self._stat_annotation = 'reimaging using "{}"'.format(label.name)
try:
# Note, only 1 reimage at any given time, this is guaranteed in
# ImageMachine, so no sync needed below.
retval = self._sched.get_experiment().machine_manager.ImageMachine(
self._dut, label)
if retval:
return 1
except RuntimeError:
return 1
self._dut.label = label
return 0
def _execute_benchmark_run(self, br):
"""Execute a single benchmark_run.
Note - this function never throws exceptions.
"""
# Termination could happen anywhere, check it.
if self._terminated:
return
self._logger.LogOutput('{} started working on {}'.format(self, br))
self._stat_num_br_run += 1
self._stat_annotation = 'executing {}'.format(br)
# benchmark_run.run does not throws, but just play it safe here.
try:
assert br.owner_thread is None
br.owner_thread = self
with self._active_br_lock:
self._active_br = br
br.run()
finally:
self._sched.get_experiment().BenchmarkRunFinished(br)
with self._active_br_lock:
self._active_br = None
def _setup_dut_label(self):
"""Try to match dut image with a certain experiment label.
If such match is found, we just skip doing reimage and jump to execute
some benchmark_runs.
"""
checksum_file = '/usr/local/osimage_checksum_file'
try:
rv, checksum, _ = command_executer.GetCommandExecuter().\
CrosRunCommandWOutput(
'cat ' + checksum_file,
chromeos_root=self._sched.get_labels(0).chromeos_root,
machine=self._dut.name,
print_to_console=False)
if rv == 0:
checksum = checksum.strip()
for l in self._sched.get_labels():
if l.checksum == checksum:
self._logger.LogOutput(
"Dut '{}' is pre-installed with '{}'".format(self._dut.name, l))
self._dut.label = l
return
except RuntimeError:
traceback.print_exc(file=sys.stdout)
self._dut.label = None
def __str__(self):
return 'DutWorker[dut="{}", label="{}"]'.format(
self._dut.name, self._dut.label.name if self._dut.label else 'None')
def dut(self):
return self._dut
def status_str(self):
"""Report thread status."""
return ('Worker thread "{}", label="{}", benchmark_run={}, '
'reimage={}, now {}'.format(
self._dut.name, 'None' if self._dut.label is None else
self._dut.label.name, self._stat_num_br_run,
self._stat_num_reimage, self._stat_annotation))
class BenchmarkRunCacheReader(Thread):
"""The thread to read cache for a list of benchmark_runs.
On creation, each instance of this class is given a br_list, which is a
subset of experiment._benchmark_runs.
"""
def __init__(self, schedv2, br_list):
super(BenchmarkRunCacheReader, self).__init__()
self._schedv2 = schedv2
self._br_list = br_list
self._logger = self._schedv2.get_logger()
def run(self):
for br in self._br_list:
try:
br.ReadCache()
if br.cache_hit:
self._logger.LogOutput('Cache hit - {}'.format(br))
with self._schedv2.lock_on('_cached_br_list'):
self._schedv2.get_cached_run_list().append(br)
else:
self._logger.LogOutput('Cache not hit - {}'.format(br))
except RuntimeError:
traceback.print_exc(file=sys.stderr)
class Schedv2(object):
"""New scheduler for crosperf."""
def __init__(self, experiment):
self._experiment = experiment
self._logger = logger.GetLogger(experiment.log_dir)
# Create shortcuts to nested data structure. "_duts" points to a list of
# locked machines. _labels points to a list of all labels.
self._duts = self._experiment.machine_manager.GetMachines()
self._labels = self._experiment.labels
# Bookkeeping for synchronization.
self._workers_lock = Lock()
# pylint: disable=unnecessary-lambda
self._lock_map = defaultdict(lambda: Lock())
# Test mode flag
self._in_test_mode = test_flag.GetTestMode()
# Read benchmarkrun cache.
self._read_br_cache()
# Mapping from label to a list of benchmark_runs.
self._label_brl_map = dict((l, []) for l in self._labels)
for br in self._experiment.benchmark_runs:
assert br.label in self._label_brl_map
# Only put no-cache-hit br into the map.
if br not in self._cached_br_list:
self._label_brl_map[br.label].append(br)
# Use machine image manager to calculate initial label allocation.
self._mim = MachineImageManager(self._labels, self._duts)
self._mim.compute_initial_allocation()
# Create worker thread, 1 per dut.
self._active_workers = [DutWorker(dut, self) for dut in self._duts]
self._finished_workers = []
# Termination flag.
self._terminated = False
def run_sched(self):
"""Start all dut worker threads and return immediately."""
for w in self._active_workers:
w.start()
def _read_br_cache(self):
"""Use multi-threading to read cache for all benchmarkruns.
We do this by firstly creating a few threads, and then assign each
thread a segment of all brs. Each thread will check cache status for
each br and put those with cache into '_cached_br_list'.
"""
self._cached_br_list = []
n_benchmarkruns = len(self._experiment.benchmark_runs)
if n_benchmarkruns <= 4:
# Use single thread to read cache.
self._logger.LogOutput(('Starting to read cache status for '
'{} benchmark runs ...').format(n_benchmarkruns))
BenchmarkRunCacheReader(self, self._experiment.benchmark_runs).run()
return
# Split benchmarkruns set into segments. Each segment will be handled by
# a thread. Note, we use (x+3)/4 to mimic math.ceil(x/4).
n_threads = max(2, min(20, (n_benchmarkruns + 3) / 4))
self._logger.LogOutput(('Starting {} threads to read cache status for '
'{} benchmark runs ...').format(
n_threads, n_benchmarkruns))
benchmarkruns_per_thread = (n_benchmarkruns + n_threads - 1) / n_threads
benchmarkrun_segments = []
for i in range(n_threads - 1):
start = i * benchmarkruns_per_thread
end = (i + 1) * benchmarkruns_per_thread
benchmarkrun_segments.append(self._experiment.benchmark_runs[start:end])
benchmarkrun_segments.append(self._experiment.benchmark_runs[(
n_threads - 1) * benchmarkruns_per_thread:])
# Assert: aggregation of benchmarkrun_segments equals to benchmark_runs.
assert sum(len(x) for x in benchmarkrun_segments) == n_benchmarkruns
# Create and start all readers.
cache_readers = [
BenchmarkRunCacheReader(self, x) for x in benchmarkrun_segments
]
for x in cache_readers:
x.start()
# Wait till all readers finish.
for x in cache_readers:
x.join()
# Summarize.
self._logger.LogOutput('Total {} cache hit out of {} benchmark_runs.'.
format(len(self._cached_br_list), n_benchmarkruns))
def get_cached_run_list(self):
return self._cached_br_list
def get_label_map(self):
return self._label_brl_map
def get_experiment(self):
return self._experiment
def get_labels(self, i=None):
if i == None:
return self._labels
return self._labels[i]
def get_logger(self):
return self._logger
def get_cached_benchmark_run(self):
"""Get a benchmark_run with 'cache hit'.
Returns:
The benchmark that has cache hit, if any. Otherwise none.
"""
with self.lock_on('_cached_br_list'):
if self._cached_br_list:
return self._cached_br_list.pop()
return None
def get_benchmark_run(self, dut):
"""Get a benchmark_run (br) object for a certain dut.
Args:
dut: the dut for which a br is returned.
Returns:
A br with its label matching that of the dut. If no such br could be
found, return None (this usually means a reimage is required for the
dut).
"""
# If terminated, stop providing any br.
if self._terminated:
return None
# If dut bears an unrecognized label, return None.
if dut.label is None:
return None
# If br list for the dut's label is empty (that means all brs for this
# label have been done), return None.
with self.lock_on(dut.label):
brl = self._label_brl_map[dut.label]
if not brl:
return None
# Return the first br.
return brl.pop(0)
def allocate_label(self, dut):
"""Allocate a label to a dut.
The work is delegated to MachineImageManager.
The dut_worker calling this method is responsible for reimage the dut to
this label.
Args:
dut: the new label that is to be reimaged onto the dut.
Returns:
The label or None.
"""
if self._terminated:
return None
return self._mim.allocate(dut, self)
def dut_worker_finished(self, dut_worker):
"""Notify schedv2 that the dut_worker thread finished.
Args:
dut_worker: the thread that is about to end.
"""
self._logger.LogOutput('{} finished.'.format(dut_worker))
with self._workers_lock:
self._active_workers.remove(dut_worker)
self._finished_workers.append(dut_worker)
def is_complete(self):
return len(self._active_workers) == 0
def lock_on(self, my_object):
return self._lock_map[my_object]
def terminate(self):
"""Mark flag so we stop providing br/reimages.
Also terminate each DutWorker, so they refuse to execute br or reimage.
"""
self._terminated = True
for dut_worker in self._active_workers:
dut_worker.terminate()
def threads_status_as_string(self):
"""Report the dut worker threads status."""
status = '{} active threads, {} finished threads.\n'.format(
len(self._active_workers), len(self._finished_workers))
status += ' Active threads:'
for dw in self._active_workers:
status += '\n ' + dw.status_str()
if self._finished_workers:
status += '\n Finished threads:'
for dw in self._finished_workers:
status += '\n ' + dw.status_str()
return status