def __init__(self, home='.'):
"""Creates a new task processor operating out of the current working
directory. Uses processor.cfg as the config file.
home -- The directory to run the processor out of.
"""
self._home = os.path.abspath(home)
# Once we have home set up, do everything in a try and log the error if
# we get one
try:
self.config = Config(self.getPath("processor.cfg"))['processor']
allowed = [ 'taskDatabase', 'pythonPath'
, 'threaded', 'rconsole'
]
for k in self.config.keys():
if k not in allowed:
raise ValueError(
"Processor parameter '{0}' unrecognized".format(k))
connection = Connection(self.config['taskDatabase'])
connection._ensureIndexes()
self.taskConnection = connection
# Add other path elements before trying imports
for i,path in enumerate(self.config.get('pythonPath', [])):
sys.path.insert(
i
, os.path.abspath(os.path.join(home, path))
)
self._tasksAvailable = self._getTasksAvailable(self._home)
self._monitors = {}
self._cleanupThread = None
self._cleanupThread_doc = """Thread that cleans up the _LOG_DIR"""
self._startTaskQueue = Queue()
self._stopOnNoTasks = False
self._useRConsole = self.config.get('rconsole', False)
except:
self.error('During init')
raise
class Processor(object):
"""Processes tasks for the given db. Also performs certain administrative
actions (or ensures that they are performed) on the tasks database.
"""
LOGFILE = 'processor.log'
LOAD_SLEEP_SCALE = 0.1
LOAD_SLEEP_SCALE_doc = """Seconds to wait for a running task to finish
before starting a parallel task. Scaled by system load divided
by number of cores. Set to 0 for tests, which will disable both
this and LOAD_SLEEP_SCALE_NO_TASK."""
LOAD_SLEEP_SCALE_NO_TASK = 4.0
LOAD_SLEEP_SCALE_NO_TASK_doc = """LOAD_SLEEP_SCALE for when we tried to
get a task but none were waiting"""
CLEANUP_INTERVAL = 3600
CLEANUP_INTERVAL_doc = """Seconds between cleaning up logs"""
KEEP_LOGS_FOR = 30*24*60*60
KEEP_LOGS_FOR_doc = """Seconds to keep logs around for"""
_LOG_DIR = "logs/"
_LOG_DIR_doc = """Directory used for logs; only for testing. Must end
in slash."""
KILL_INTERVAL = 5
KILL_INTERVAL_doc = """Seconds between checking if we should kill a task"""
KILL_TOLERANCE = 10
KILL_TOLERANCE_doc = """Min seconds between sending a kill message to a
task. Used to prevent killing cleanup code."""
MONITOR_CHECK_INTERVAL = 0.01
MONITOR_CHECK_INTERVAL_doc = """Minimum seconds between checking if tasks
have died."""
def __init__(self, home='.'):
"""Creates a new task processor operating out of the current working
directory. Uses processor.cfg as the config file.
home -- The directory to run the processor out of.
"""
self._home = os.path.abspath(home)
# Once we have home set up, do everything in a try and log the error if
# we get one
try:
self.config = Config(self.getPath("processor.cfg"))['processor']
allowed = [ 'taskDatabase', 'pythonPath'
, 'threaded', 'rconsole'
]
for k in self.config.keys():
if k not in allowed:
raise ValueError(
"Processor parameter '{0}' unrecognized".format(k))
connection = Connection(self.config['taskDatabase'])
connection._ensureIndexes()
self.taskConnection = connection
# Add other path elements before trying imports
for i,path in enumerate(self.config.get('pythonPath', [])):
sys.path.insert(
i
, os.path.abspath(os.path.join(home, path))
)
self._tasksAvailable = self._getTasksAvailable(self._home)
self._monitors = {}
self._cleanupThread = None
self._cleanupThread_doc = """Thread that cleans up the _LOG_DIR"""
self._startTaskQueue = Queue()
self._stopOnNoTasks = False
self._useRConsole = self.config.get('rconsole', False)
except:
self.error('During init')
raise
def error(self, message):
error = traceback.format_exc()
self.log("{0} - {1}".format(message, error))
@classmethod
def fork(cls, home='.', killExisting=True):
"""Forks a new subprocess to run a Processor instance out of the
given home directory. Useful for e.g. debug environments, where the
main script should also spawn a processor but perhaps does something
else, like serving webpages.
The fork is automatically registered with an atexit to terminate the
forked Processor. Look at lamegame_tasking/bin/lgTaskProcessor for
a standalone script.
Automatically forwards site.ENABLE_USER_SITE to forked interpreter.
Returns the function that is already registered with atexit, but may
be called manually if you need to kill the fork.
killExisting, if True, will kill any processor holding
the lock that this processor will need (thus freeing the lock). Since
fork() is primarily meant for debugging code that expects the fork
to always be running with the latest version, this defaults to True.
"""
hasS = ('-s' in sys.argv)
runProcess = os.path.abspath(os.path.join(
__file__
, '../../bin/lgTaskProcessor'
))
args = [ sys.executable ]
# site.ENABLE_USER_SITE tells us if, for instance, -s was passed
if not site.ENABLE_USER_SITE:
args.append('-s')
args.extend([ runProcess, home ])
if killExisting:
args.append('-killExisting')
args = tuple(args)
proc = subprocess.Popen(args, close_fds = True)
def terminateProc():
# We have to both terminate AND wait, or we'll get defunct
# processes lying around
if proc.poll() is None:
# Process is still running
proc.terminate()
proc.wait()
atexit.register(terminateProc)
return terminateProc
def getPath(self, path):
"""Returns the absolute path for path, taking into account our
home directory.
"""
return self._home + '/' + path
def log(self, message):
now = datetime.datetime.utcnow().isoformat()
print(message)
open(self.getPath(self._LOG_DIR + self.LOGFILE), 'a').write(
"[{0}] {1}\n".format(now, message)
)
def run(self, killExisting=False):
"""Run indefinitely or (for debugging) until no tasks are available.
If killExisting is specified, then forcibly break the lock by killing
the process that currently has the lock.
"""
# .lock is automatically appended to FileLock (processor.lock)
self._lock = ProcessorLock(self._home + '/.processor.lock')
# raises ProcessorAlreadyRunningError on fail
self._lock.acquire(killExisting=killExisting)
try:
try:
os.makedirs(self._home + '/logs')
except OSError:
pass
try:
os.makedirs(self._home + '/pids')
except OSError:
pass
self.log("Tasks loaded: {0}".format(self._tasksAvailable.keys()))
# Can we use psutil?
try:
import psutil
self._psutil = psutil
except ImportError:
self.log("No stats, install psutil for stats")
self._psutil = None
# The advantage to multiprocessing is that since we are forking
# the process, our libraries don't need to load again. This
# means that the startup time for new tasks is substantially
# (~ 0.5 sec in my tests) faster.
# The disadvantage is that there's a bug in python 2.6 that
# prohibits it from working from non-main threads.
self._useMultiprocessing = (
sys.version_info[0] >= 3
or sys.version_info[1] >= 7
or threading.current_thread().name == 'MainThread'
)
# Threaded tasks execute in a slave process to the processor itself.
# There are a few reasons for this:
# 1. If code changes, and we need to reboot the processor, the
# slave process can finish running its tasks before exiting
# but the processor can restart and keep going with new tasks.
# 2. If a task misbehaves and wreaks havoc, the processor itself
# will not be affected.
self._useThreading = (
self._useMultiprocessing
and self.config.get('threaded', False)
)
if self._useThreading:
self._useMultiprocessing = False
self.log("Using threading")
self._slaves = [ None ] * multiprocessing.cpu_count()
elif self._useMultiprocessing:
self.log("Using multiprocessing")
else:
self.log("Not using multiprocessing - detected non-main thread")
self.log("Processor started - pid " + str(os.getpid()))
# Start monitoring our starting pids
self._monitorCurrentPids()
# Run the scheduler loop; start with 1 task running at a time
self._startTaskQueue.put('any')
lastScheduler = time.time()
lastMonitor = 0.0
lastMonitorCheck = 0.0
self._lastMonitorCheckKill = 0.0
lastStats = 0.0
loadMult = self.LOAD_SLEEP_SCALE
lastCleanup = 0.0
while True:
lastScheduler = self._schedulerAudit(lastScheduler)
lastMonitor = self._monitorAudit(lastMonitor)
lastMonitorCheck = self._monitorCheckAudit(lastMonitorCheck)
lastStats = self._statsAudit(lastStats)
lastCleanup = self._cleanupAudit(lastCleanup)
try:
load = os.getloadavg()[0] / multiprocessing.cpu_count()
loadSleep = min(10.0, loadMult * load)
if loadSleep > 0:
# We need to wait for either a running task to stop
# or our timeout to be met
self._startTaskQueue.get(timeout=loadSleep)
except Empty:
# Timeout, no task start tokens are available.
# Time to run scheduler again.
# For now, we can safely assume that this always means that
# any tasks running are long-running, and can grab a new
# token.
pass
# We got a token or timed out, OK to start a new task
loadMult = self.LOAD_SLEEP_SCALE
try:
result = self._consume()
except _ProcessorStop:
raise
except (Exception, OSError):
# _consume has its own error logging; just remove our
# extra sleep bonus and try again
continue
if not result:
# Failed to get a new task, avoid using cpu
if self.LOAD_SLEEP_SCALE > 0:
# Otherwise it's a test, so don't sleep
loadMult = self.LOAD_SLEEP_SCALE_NO_TASK
if len(self._monitors) == 0:
if self._stopOnNoTasks:
# This is a test, we're not running anything,
# so done
break
except _ProcessorStop:
self.error("Received _ProcessorStop")
except Exception:
self.error("Unhandled error, exiting")
finally:
self._lock.release()
def start(self):
"""Run the Processor asynchronously for test cases.
"""
self.LOAD_SLEEP_SCALE = 0.0
self._thread = InterruptableThread(target=self.run)
self._thread.start()
'''
def withProfile(self):
import cProfile
p = cProfile.Profile(builtins = False, subcalls = False)
p.runctx('self.run()', globals(), locals())
from io import BytesIO
buffer = BytesIO()
import pstats
pr = pstats.Stats(p, stream = buffer)
pr.sort_stats("cumulative")
pr.print_stats()
open('processor.profile', 'w').write(buffer.getvalue())
self._thread = InterruptableThread(target=withProfile, args=(self,))
self._thread.start()
'''
def stop(self, timeout = 5.0):
"""Halt an asynchronously started processor (only use this for tests!).
Also kills all tasks.
timeout -- Max # of seconds to run
"""
self._stopOnNoTasks = True
self._thread.join(timeout)
if self._thread.is_alive():
self._thread.raiseException(_ProcessorStop)
while self._thread.is_alive():
time.sleep(0.1)
# Now kill our tasks
pids = [ d[1] for d in self._monitors.itervalues() ]
for p in pids:
try:
os.kill(p, signal.SIGKILL)
except OSError, e:
if e.errno == 3:
# No such process
continue
raise
