def _fast_forward_stream(self, process_name):
log.debug('Fast forwarding %s stream to seq=%s' % (process_name,
self._watermarks[process_name]))
assert self._processes.get(process_name) is not None
fp = self._processes[process_name]
rr = ThriftRecordReader(fp, RunnerCkpt)
current_watermark = -1
records = 0
while current_watermark < self._watermarks[process_name]:
last_pos = fp.tell()
record = rr.try_read()
if record is None:
break
new_watermark = record.process_status.seq
if new_watermark > self._watermarks[process_name]:
log.debug('Over-seeked %s [watermark = %s, high watermark = %s], rewinding.' % (
process_name, new_watermark, self._watermarks[process_name]))
fp.seek(last_pos)
break
current_watermark = new_watermark
records += 1
if current_watermark < self._watermarks[process_name]:
log.warning('Only able to fast forward to %s@sequence=%s, high watermark is %s' % (
process_name, current_watermark, self._watermarks[process_name]))
if records:
log.debug('Fast forwarded %s %s record(s) to seq=%s.' % (process_name, records,
current_watermark))
def _wait_for_control(self):
"""Wait for control of the checkpoint stream: must be run in the child."""
total_wait_time = Amount(0, Time.SECONDS)
with open(self.ckpt_file(), 'r') as fp:
fp.seek(self._ckpt_head)
rr = ThriftRecordReader(fp, RunnerCkpt)
while total_wait_time < self.MAXIMUM_CONTROL_WAIT:
ckpt_tail = os.path.getsize(self.ckpt_file())
if ckpt_tail == self._ckpt_head:
self._platform.clock().sleep(self.CONTROL_WAIT_CHECK_INTERVAL.as_(Time.SECONDS))
total_wait_time += self.CONTROL_WAIT_CHECK_INTERVAL
continue
checkpoint = rr.try_read()
if checkpoint:
if not checkpoint.process_status:
raise self.CheckpointError('No process status in checkpoint!')
if (checkpoint.process_status.process != self.name() or
checkpoint.process_status.state != ProcessState.FORKED or
checkpoint.process_status.fork_time != self._fork_time or
checkpoint.process_status.coordinator_pid != self._pid):
self._log('Losing control of the checkpoint stream:')
self._log(' fork_time [%s] vs self._fork_time [%s]' % (
checkpoint.process_status.fork_time, self._fork_time))
self._log(' coordinator_pid [%s] vs self._pid [%s]' % (
checkpoint.process_status.coordinator_pid, self._pid))
raise self.CheckpointError('Lost control of the checkpoint stream!')
self._log('Taking control of the checkpoint stream at record: %s' %
checkpoint.process_status)
self._seq = checkpoint.process_status.seq + 1
return True
raise self.CheckpointError('Timed out waiting for checkpoint stream!')
def select(self):
"""
Read and multiplex checkpoint records from all the forked off process coordinators.
Checkpoint records can come from one of two places:
in-process: checkpoint records synthesized for FORKED and LOST events
out-of-process: checkpoint records from from file descriptors of forked coordinators
Returns a list of RunnerCkpt objects that were successfully read, or an empty
list if none were read.
"""
self._bind_processes()
updates = []
for handle in filter(None, self._processes.values()):
try:
fstat = os.fstat(handle.fileno())
except OSError as e:
log.error('Unable to fstat %s!' % handle.name)
continue
if handle.tell() > fstat.st_size:
log.error('Truncated checkpoint record detected on %s!' % handle.name)
elif handle.tell() < fstat.st_size:
rr = ThriftRecordReader(handle, RunnerCkpt)
while True:
process_update = rr.try_read()
if process_update:
updates.append(process_update)
else:
break
if len(updates) > 0:
log.debug('select() returning %s updates:' % len(updates))
for update in updates:
log.debug(' = %s' % update)
return updates
def _apply_states(self):
"""
os.stat() the corresponding checkpoint stream of this task and determine if there are new ckpt
records. Attempt to read those records and update the high watermark for that stream.
Returns True if new states were applied, False otherwise.
"""
ckpt_offset = None
try:
ckpt_offset = os.stat(self._runner_ckpt).st_size
updated = False
if self._ckpt_head < ckpt_offset:
with open(self._runner_ckpt, 'r') as fp:
fp.seek(self._ckpt_head)
rr = ThriftRecordReader(fp, RunnerCkpt)
while True:
runner_update = rr.try_read()
if not runner_update:
break
try:
self._dispatcher.dispatch(self._runnerstate, runner_update)
except CheckpointDispatcher.InvalidSequenceNumber as e:
log.error('Checkpoint stream is corrupt: %s' % e)
break
new_ckpt_head = fp.tell()
updated = self._ckpt_head != new_ckpt_head
self._ckpt_head = new_ckpt_head
return updated
except OSError as e:
if e.errno == errno.ENOENT:
# The log doesn't yet exist, will retry later.
log.warning('Could not read from checkpoint %s' % self._runner_ckpt)
return False
else:
raise
def _apply_states(self):
"""
os.stat() the corresponding checkpoint stream of this task and determine if there are new ckpt
records. Attempt to read those records and update the high watermark for that stream.
Returns True if new states were applied, False otherwise.
"""
ckpt_offset = None
try:
ckpt_offset = os.stat(self._runner_ckpt).st_size
updated = False
if self._ckpt_head < ckpt_offset:
with open(self._runner_ckpt, "r") as fp:
fp.seek(self._ckpt_head)
rr = ThriftRecordReader(fp, RunnerCkpt)
while True:
runner_update = rr.try_read()
if not runner_update:
break
try:
self._dispatcher.dispatch(self._runnerstate, runner_update)
except CheckpointDispatcher.InvalidSequenceNumber as e:
log.error("Checkpoint stream is corrupt: %s" % e)
break
new_ckpt_head = fp.tell()
updated = self._ckpt_head != new_ckpt_head
self._ckpt_head = new_ckpt_head
return updated
except OSError as e:
if e.errno == errno.ENOENT:
# The log doesn't yet exist, will retry later.
log.warning("Could not read from checkpoint %s" % self._runner_ckpt)
return False
else:
raise
def _wait_for_control(self):
"""Wait for control of the checkpoint stream: must be run in the child."""
total_wait_time = Amount(0, Time.SECONDS)
with open(self.ckpt_file(), 'r') as fp:
fp.seek(self._ckpt_head)
rr = ThriftRecordReader(fp, RunnerCkpt)
while total_wait_time < self.MAXIMUM_CONTROL_WAIT:
ckpt_tail = os.path.getsize(self.ckpt_file())
if ckpt_tail == self._ckpt_head:
self._platform.clock().sleep(self.CONTROL_WAIT_CHECK_INTERVAL.as_(Time.SECONDS))
total_wait_time += self.CONTROL_WAIT_CHECK_INTERVAL
continue
checkpoint = rr.try_read()
if checkpoint:
if not checkpoint.process_status:
raise self.CheckpointError('No process status in checkpoint!')
if (checkpoint.process_status.process != self.name() or
checkpoint.process_status.state != ProcessState.FORKED or
checkpoint.process_status.fork_time != self._fork_time or
checkpoint.process_status.coordinator_pid != self._pid):
self._log('Losing control of the checkpoint stream:')
self._log(' fork_time [%s] vs self._fork_time [%s]' % (
checkpoint.process_status.fork_time, self._fork_time))
self._log(' coordinator_pid [%s] vs self._pid [%s]' % (
checkpoint.process_status.coordinator_pid, self._pid))
raise self.CheckpointError('Lost control of the checkpoint stream!')
self._log('Taking control of the checkpoint stream at record: %s' %
checkpoint.process_status)
self._seq = checkpoint.process_status.seq + 1
return True
raise self.CheckpointError('Timed out waiting for checkpoint stream!')
def _fast_forward_stream(self, process_name):
log.debug('Fast forwarding %s stream to seq=%s' %
(process_name, self._watermarks[process_name]))
assert self._processes.get(process_name) is not None
fp = self._processes[process_name]
rr = ThriftRecordReader(fp, RunnerCkpt)
current_watermark = -1
records = 0
while current_watermark < self._watermarks[process_name]:
last_pos = fp.tell()
record = rr.try_read()
if record is None:
break
new_watermark = record.process_status.seq
if new_watermark > self._watermarks[process_name]:
log.debug(
'Over-seeked %s [watermark = %s, high watermark = %s], rewinding.'
% (process_name, new_watermark,
self._watermarks[process_name]))
fp.seek(last_pos)
break
current_watermark = new_watermark
records += 1
if current_watermark < self._watermarks[process_name]:
log.warning(
'Only able to fast forward to %s@sequence=%s, high watermark is %s'
% (process_name, current_watermark,
self._watermarks[process_name]))
if records:
log.debug('Fast forwarded %s %s record(s) to seq=%s.' %
(process_name, records, current_watermark))
def select(self):
"""
Read and multiplex checkpoint records from all the forked off process coordinators.
Checkpoint records can come from one of two places:
in-process: checkpoint records synthesized for FORKED and LOST events
out-of-process: checkpoint records from from file descriptors of forked coordinators
Returns a list of RunnerCkpt objects that were successfully read, or an empty
list if none were read.
"""
self._bind_processes()
updates = []
for handle in filter(None, self._processes.values()):
try:
fstat = os.fstat(handle.fileno())
except OSError:
log.error('Unable to fstat %s!' % handle.name)
continue
if handle.tell() > fstat.st_size:
log.error('Truncated checkpoint record detected on %s!' %
handle.name)
elif handle.tell() < fstat.st_size:
rr = ThriftRecordReader(handle, RunnerCkpt)
while True:
process_update = rr.try_read()
if process_update:
updates.append(process_update)
else:
break
if len(updates) > 0:
log.debug('select() returning %s updates:' % len(updates))
for update in updates:
log.debug(' = %s' % update)
return updates
def wait_for_rc(checkpoint, timeout=5.0):
start = time.time()
trr = ThriftRecordReader(open(checkpoint), RunnerCkpt)
while time.time() < start + timeout:
record = trr.read()
if record and record.process_status and record.process_status.return_code is not None:
return record.process_status.return_code
else:
time.sleep(0.1)
def wait_for_rc(checkpoint, timeout=5.0):
start = time.time()
trr = ThriftRecordReader(open(checkpoint), RunnerCkpt)
while time.time() < start + timeout:
record = trr.read()
if record and record.process_status and record.process_status.return_code is not None:
return record.process_status.return_code
else:
time.sleep(0.1)
def test_thrift_garbage():
with EphemeralFile('w') as fp:
fn = fp.name
fp.write(struct.pack('>L', 2))
fp.write('ab')
fp.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
with pytest.raises(RecordIO.PrematureEndOfStream):
rr.read()
def _replay_runner_ckpt(self):
"""
Replay the checkpoint stream associated with this task.
"""
ckpt_file = self._pathspec.getpath('runner_checkpoint')
if os.path.exists(ckpt_file):
fp = open(ckpt_file, "r")
ckpt_recover = ThriftRecordReader(fp, RunnerCkpt)
for record in ckpt_recover:
log.debug('Replaying runner checkpoint record: %s' % record)
self._dispatcher.dispatch(self._state, record, recovery=True)
ckpt_recover.close()
def _replay_runner_ckpt(self):
"""
Replay the checkpoint stream associated with this task.
"""
ckpt_file = self._pathspec.getpath('runner_checkpoint')
if os.path.exists(ckpt_file):
fp = open(ckpt_file, "r")
ckpt_recover = ThriftRecordReader(fp, RunnerCkpt)
for record in ckpt_recover:
log.debug('Replaying runner checkpoint record: %s' % record)
self._dispatcher.dispatch(self._state, record, recovery=True)
ckpt_recover.close()
def test_thrift_garbage():
with EphemeralFile('w') as fp:
fn = fp.name
fp.write(struct.pack('>L', 2))
fp.write('ab')
fp.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
with pytest.raises(RecordIO.PrematureEndOfStream):
rr.read()
def test_basic_thriftrecordwriter_write():
test_string = StringType("hello world")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string)
rw.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string
def test_basic_thriftrecordwriter_write():
test_string = StringType("hello world")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string)
rw.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string
def test_paranoid_thrift_append_framing():
test_string_1 = StringType("hello world")
test_string_2 = StringType("ahoy ahoy, bonjour")
with EphemeralFile('w') as fp:
fn = fp.name
ThriftRecordWriter.append(fn, test_string_1)
ThriftRecordWriter.append(fn, test_string_2)
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string_1
assert rr.read() == test_string_2
def test_thrift_recordwriter_type_mismatch():
test_string = StringType("hello world")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string)
rw.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, IntType)
# This is a peculiar behavior of Thrift in that it just returns
# ThriftType() with no serialization applied
assert rr.read() == IntType()
def test_paranoid_thrift_append_framing():
test_string_1 = StringType("hello world")
test_string_2 = StringType("ahoy ahoy, bonjour")
with EphemeralFile('w') as fp:
fn = fp.name
ThriftRecordWriter.append(fn, test_string_1)
ThriftRecordWriter.append(fn, test_string_2)
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string_1
assert rr.read() == test_string_2
def test_thrift_recordwriter_type_mismatch():
test_string = StringType("hello world")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string)
rw.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, IntType)
# This is a peculiar behavior of Thrift in that it just returns
# ThriftType() with no serialization applied
assert rr.read() == IntType()
def iter_updates(cls, filename):
try:
with open(filename) as fp:
rr = ThriftRecordReader(fp, RunnerCkpt)
for update in rr:
yield update
except (IOError, OSError, RecordIO.Error) as err:
raise cls.ErrorRecoveringState(err)
def read(args, options):
"""Replay a thermos checkpoint.
Usage: thermos read [options] checkpoint_filename
Options:
--simple Do not replay the full task state machine. Only print out the contents of
each checkpoint log message.
"""
if len(args) != 1:
app.error('Expected one checkpoint file, got %s' % len(args))
if not os.path.exists(args[0]):
app.error('Could not find %s' % args[0])
dispatcher = CheckpointDispatcher()
state = RunnerState(processes={})
with open(args[0], 'r') as fp:
try:
for record in ThriftRecordReader(fp, RunnerCkpt):
if not options.simple:
dispatcher.dispatch(state, record)
else:
print('CKPT: %s' % record)
except RecordIO.Error as err:
print("Failed to recover from %s: %s" % (fp.name, err))
return
if not options.simple:
if state is None or state.header is None:
print('Checkpoint stream CORRUPT or outdated format')
return
print('Recovered Task Header:')
print(' id: %s' % state.header.task_id)
print(' user: %s' % state.header.user)
print(' host: %s' % state.header.hostname)
print(' sandbox: %s' % state.header.sandbox)
if state.header.ports:
print(' ports: %s' %
' '.join('%s->%s' % (name, port)
for (name, port) in state.header.ports.items()))
print('Recovered Task States:')
for task_status in state.statuses:
print(
' %s [pid: %d] => %s' %
(time.asctime(time.localtime(task_status.timestamp_ms /
1000.0)), task_status.runner_pid,
TaskState._VALUES_TO_NAMES[task_status.state]))
print('Recovered Processes:')
for process, process_history in state.processes.items():
print(' %s runs: %s' % (process, len(process_history)))
for k in reversed(range(len(process_history))):
run = process_history[k]
print(
' %2d: pid=%d, rc=%s, finish:%s, state:%s' %
(k, run.pid, run.return_code if run.return_code is not None
else '', time.asctime(time.localtime(run.stop_time))
if run.stop_time else 'None',
ProcessState._VALUES_TO_NAMES.get(run.state, 'Unknown')))
def test_thriftrecordwriter_framing():
test_string_1 = StringType("hello world")
test_string_2 = StringType("ahoy ahoy, bonjour")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string_1)
rw.close()
with open(fn, 'a') as fpa:
rw = ThriftRecordWriter(fpa)
rw.write(test_string_2)
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string_1
assert rr.read() == test_string_2
def test_thriftrecordwriter_framing():
test_string_1 = StringType("hello world")
test_string_2 = StringType("ahoy ahoy, bonjour")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string_1)
rw.close()
with open(fn, 'a') as fpa:
rw = ThriftRecordWriter(fpa)
rw.write(test_string_2)
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
assert rr.read() == test_string_1
assert rr.read() == test_string_2
def has_data(self, process):
"""
Return true if we think that there are updates available from the supplied process.
"""
self._bind_processes()
# TODO(wickman) Should this raise ProcessNotFound?
if process not in self._processes:
return False
fp = self._processes[process]
rr = ThriftRecordReader(fp, RunnerCkpt)
old_pos = fp.tell()
try:
os.fstat(fp.fileno()).st_size
except OSError:
log.debug('ProcessMuxer could not fstat for process %s' % process)
return False
update = rr.try_read()
if update:
fp.seek(old_pos)
return True
return False
def has_data(self, process):
"""
Return true if we think that there are updates available from the supplied process.
"""
self._bind_processes()
# TODO(wickman) Should this raise ProcessNotFound?
if process not in self._processes:
return False
fp = self._processes[process]
rr = ThriftRecordReader(fp, RunnerCkpt)
old_pos = fp.tell()
try:
expected_new_pos = os.fstat(fp.fileno()).st_size
except OSError as e:
log.debug('ProcessMuxer could not fstat for process %s' % process)
return False
update = rr.try_read()
if update:
fp.seek(old_pos)
return True
return False
def test_thriftrecordreader_iteration():
test_string_1 = StringType("hello world")
test_string_2 = StringType("ahoy ahoy, bonjour")
with EphemeralFile('w') as fp:
fn = fp.name
rw = ThriftRecordWriter(fp)
rw.write(test_string_1)
rw.write(test_string_2)
rw.close()
with open(fn) as fpr:
rr = ThriftRecordReader(fpr, StringType)
records = []
for record in rr:
records.append(record)
assert records == [test_string_1, test_string_2]
def main(args):
values = app.get_options()
if len(args) > 0:
print >> sys.stderr, "ERROR: unrecognized arguments: %s\n" % (
" ".join(args))
app.help()
sys.exit(1)
if not values.ckpt:
print >> sys.stderr, "ERROR: must supply --checkpoint"
app.help()
sys.exit(1)
fp = file(values.ckpt, "r")
rr = ThriftRecordReader(fp, RunnerCkpt)
wrs = RunnerState(processes={})
dispatcher = CheckpointDispatcher()
try:
for wts in rr:
print 'Recovering: ', wts
if values.assemble is True:
dispatcher.dispatch(wrs, wts)
except RecordIO.Error as err:
print 'Error recovering checkpoint stream: %s' % err
return
print '\n\n\n'
if values.assemble:
print 'Recovered Task Header'
pprint.pprint(wrs.header, indent=4)
print '\nRecovered Task States'
for task_status in wrs.statuses:
print ' %s [pid: %d] => %s' % (
time.asctime(time.localtime(task_status.timestamp_ms /
1000.0)), task_status.runner_pid,
TaskState._VALUES_TO_NAMES[task_status.state])
print '\nRecovered Processes'
pprint.pprint(wrs.processes, indent=4)
def inspect(self, task_id):
"""
Reconstructs the checkpoint stream and returns a CheckpointInspection.
"""
dispatcher = CheckpointDispatcher()
state = RunnerState(processes={})
muxer = ProcessMuxer(self._path.given(task_id=task_id))
runner_processes = []
coordinator_processes = set()
processes = set()
def consume_process_record(record):
if not record.process_status:
return
try:
user_uid = pwd.getpwnam(state.header.user).pw_uid
except KeyError:
log.error('Could not find user: %s' % state.header.user)
return
if record.process_status.state == ProcessState.FORKED:
coordinator_processes.add(
(record.process_status.coordinator_pid, user_uid,
record.process_status.fork_time))
elif record.process_status.state == ProcessState.RUNNING:
processes.add((record.process_status.pid, user_uid,
record.process_status.start_time))
# replay runner checkpoint
runner_pid = None
runner_latest_update = 0
try:
with open(
self._path.given(
task_id=task_id).getpath('runner_checkpoint')) as fp:
with closing(ThriftRecordReader(fp, RunnerCkpt)) as ckpt:
for record in ckpt:
dispatcher.dispatch(state, record)
runner_latest_update = max(
runner_latest_update,
self.get_timestamp(record.process_status))
# collect all bound runners
if record.task_status:
if record.task_status.runner_pid != runner_pid:
runner_processes.append(
(record.task_status.runner_pid,
record.task_status.runner_uid
or 0, record.task_status.timestamp_ms))
runner_pid = record.task_status.runner_pid
elif record.process_status:
consume_process_record(record)
except (IOError, OSError, RecordIO.Error) as err:
log.debug('Error inspecting task runner checkpoint: %s' % err)
return
# register existing processes in muxer
for process_name in state.processes:
muxer.register(process_name)
# read process checkpoints
process_latest_update = runner_latest_update
for record in muxer.select():
process_latest_update = max(
process_latest_update,
self.get_timestamp(record.process_status))
consume_process_record(record)
return CheckpointInspection(
runner_latest_update=runner_latest_update,
process_latest_update=process_latest_update,
runner_processes=runner_processes,
coordinator_processes=coordinator_processes,
processes=processes)
def test_thrift_invalid_codec_with_nonclass():
with EphemeralFile('w') as fp:
with pytest.raises(ThriftRecordIO.InvalidThriftException):
ThriftRecordReader(fp, 5)
def test_thrift_invalid_codec_with_object_instead_of_class():
with EphemeralFile('w') as fp:
with pytest.raises(ThriftRecordIO.InvalidThriftException):
ThriftRecordReader(fp, StringType())