def __init__(self, preallocator):
"""
Here we maintain several data structures used to keep track of the
jobs present for the autograder.
Live jobs contains:
- jobs that are yet to be assigned and run
- jobs that are currently running
Dead jobs contains:
- jobs that have been completed, or have been 'deleted' when in
the live jobs queue
Unassigned jobs:
This is a FIFO queue of jobs that are pending assignment.
- We enforce the invariant that all jobs in this queue must be
present in live jobs
queueLock protects all the internal data structure of JobQueue. This
is needed since there are multiple worker threads and they might be
using the makeUnassigned api.
"""
self.liveJobs = TangoDictionary("liveJobs")
self.deadJobs = TangoDictionary("deadJobs")
self.unassignedJobs = TangoQueue("unassignedLiveJobs")
self.queueLock = threading.Lock()
self.preallocator = preallocator
self.log = logging.getLogger("JobQueue")
self.nextID = 1
def update(self, vm, num):
""" update - Updates the number of machines of a certain type
to be preallocated.
This function is called via the TangoServer HTTP interface.
It will validate the request,update the machine list, and
then spawn child threads to do the creation and destruction
of machines as necessary.
"""
self.lock.acquire()
if vm.name not in self.machines:
self.machines.set(vm.name, [[], TangoQueue(vm.name)])
self.log.debug("Creating empty pool of %s instances" % (vm.name))
self.lock.release()
delta = num - len(self.machines.get(vm.name)[0])
if delta > 0:
# We need more self.machines, spin them up.
self.log.debug("update: Creating %d new %s instances" %
(delta, vm.name))
threading.Thread(target=self.__create(vm, delta)).start()
elif delta < 0:
# We have too many self.machines, remove them from the pool
self.log.debug("update: Destroying %d preallocated %s instances" %
(-delta, vm.name))
for i in range(-1 * delta):
threading.Thread(target=self.__destroy(vm)).start()
def runQueueTests(self):
self.testQueue = TangoQueue("self.testQueue")
self.expectedSize = 0
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertTrue(self.testQueue.empty())
self.addAllToQueue()
# Test the blocking get
for x in self.test_entries:
item = self.testQueue.get()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
self.addAllToQueue()
# Test the blocking get
for x in self.test_entries:
item = self.testQueue.get_nowait()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
self.addAllToQueue()
# Remove all the even entries
for x in self.test_entries:
if (x % 2 == 0):
self.testQueue.remove(x)
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
# Test that get only returns odd keys in order
for x in self.test_entries:
if (x % 2 == 1):
item = self.testQueue.get_nowait()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
def addVM(self, vm):
""" addVM - add a particular VM instance to the pool
"""
self.lock.acquire()
# REUSEV_VMS=False code path does not call Preallcator::update to
# create machine, so manually handle it here.
if vm.name not in self.machines.keys():
self.machines.set(vm.name, [[], TangoQueue(vm.name)])
self.log.debug("Creating empty pool of %s instances" % (vm.name))
machine = self.machines.get(vm.name)
machine[0].append(vm.id)
self.machines.set(vm.name, machine)
self.lock.release()
def incrementPoolSize(self, vm, delta):
"""
Called by jobQueue to create the pool and allcoate given number of vms
"""
self.log.debug("incrementPoolSize| acquiring lock on preallocator")
with self.lock:
self.log.debug("incrementPoolSize| acquired lock on preallocator")
if vm.name not in self.machines.keys():
self.machines.set(vm.name, [[], TangoQueue(vm.name)])
# see comments in jobManager.py for the same call
self.machines.get(vm.name)[1].make_empty()
self.log.debug("Creating empty pool of %s instances" %
(vm.name))
self.log.debug("incrementPoolSize| released lock on preallocator")
self.log.debug("incrementPoolSize: add %d new %s instances" %
(delta, vm.name))
threading.Thread(target=self.__create(vm, delta)).start()
"Unable to pre-allocate a vm for job job %s:%d [try %d]"
% (job.name, job.id, job.retries))
job.appendTrace(
"%s|Dispatched job %s:%d [try %d]" %
(datetime.utcnow().ctime(), job.name, job.id, job.retries))
Worker(job, vmms, self.jobQueue, self.preallocator,
preVM).start()
except Exception as err:
self.jobQueue.makeDead(job.id, str(err))
if __name__ == "__main__":
if not Config.USE_REDIS:
print(
"You need to have Redis running to be able to initiate stand-alone\
JobManager")
else:
tango = TangoServer()
tango.log.debug("Resetting Tango VMs")
tango.resetTango(tango.preallocator.vmms)
for key in tango.preallocator.machines.keys():
tango.preallocator.machines.set(key, [[], TangoQueue(key)])
jobs = JobManager(tango.jobQueue)
print("Starting the stand-alone Tango JobManager")
jobs.run()
class JobQueue(object):
def __init__(self, preallocator):
"""
Here we maintain several data structures used to keep track of the
jobs present for the autograder.
Live jobs contains:
- jobs that are yet to be assigned and run
- jobs that are currently running
Dead jobs contains:
- jobs that have been completed, or have been 'deleted' when in
the live jobs queue
Unassigned jobs:
This is a FIFO queue of jobs that are pending assignment.
- We enforce the invariant that all jobs in this queue must be
present in live jobs
queueLock protects all the internal data structure of JobQueue. This
is needed since there are multiple worker threads and they might be
using the makeUnassigned api.
"""
self.liveJobs = TangoDictionary("liveJobs")
self.deadJobs = TangoDictionary("deadJobs")
self.unassignedJobs = TangoQueue("unassignedLiveJobs")
self.queueLock = threading.Lock()
self.preallocator = preallocator
self.log = logging.getLogger("JobQueue")
self.nextID = 1
def _getNextID(self):
"""_getNextID - updates and returns the next ID to be used for a job
Jobs have ID's between 1 and MAX_JOBID.
"""
self.log.debug("_getNextID|Acquiring lock to job queue.")
self.queueLock.acquire()
self.log.debug("_getNextID|Acquired lock to job queue.")
id = self.nextID
# If there is an livejob in the queue with with nextID,
# this means that the id is already taken.
# We try to find a free id to use by looping through all
# the job ids possible and finding one that is
# not used by any of the livejobs.
# Return -1 if no such free id is found.
keys = self.liveJobs.keys()
if (str(id) in keys):
id = -1
for i in range(1, Config.MAX_JOBID + 1):
if (str(i) not in keys):
id = i
break
self.nextID += 1
if self.nextID > Config.MAX_JOBID:
# Wrap around if job ids go over max job ids avail
self.nextID = 1
self.queueLock.release()
self.log.debug("_getNextID|Released lock to job queue.")
return id
def remove(self, id):
"""remove - Remove job from live queue
"""
status = -1
self.log.debug("remove|Acquiring lock to job queue.")
self.queueLock.acquire()
self.log.debug("remove|Acquired lock to job queue.")
if id in self.liveJobs:
self.liveJobs.delete(id)
status = 0
self.unassignedJobs.remove(int(id))
self.queueLock.release()
self.log.debug("remove|Relased lock to job queue.")
if status == 0:
self.log.debug("Removed job %s from queue" % id)
else:
self.log.error("Job %s not found in queue" % id)
return status
def add(self, job):
"""add - add job to live queue
This function assigns an ID number to a *new* job and then adds it
to the queue of live jobs.
Returns the job id on success, -1 otherwise
"""
if (not isinstance(job, TangoJob)):
return -1
# Get an id for the new job
self.log.debug("add|Getting next ID")
nextId = self._getNextID()
if (nextId == -1):
self.log.info("add|JobQueue is full")
return -1
job.setId(nextId)
self.log.debug("add|Gotten next ID: " + str(job.id))
self.log.info("add|Unassigning job ID: %d" % (job.id))
# Make the job unassigned
job.makeUnassigned()
# Since we assume that the job is new, we set the number of retries
# of this job to 0
job.retries = 0
# Add the job to the queue. Careful not to append the trace until we
# know the job has actually been added to the queue.
self.log.debug("add|Acquiring lock to job queue.")
self.queueLock.acquire()
self.log.debug("add| Acquired lock to job queue.")
# Adds the job to the live jobs dictionary
self.liveJobs.set(job.id, job)
# Add this to the unassigned job queue too
self.unassignedJobs.put(int(job.id))
job.appendTrace("%s|Added job %s:%d to queue" %
(datetime.utcnow().ctime(), job.name, job.id))
self.log.debug("Ref: " + str(job._remoteLocation))
self.log.debug("job_id: " + str(job.id))
self.log.debug("job_name: " + str(job.name))
self.queueLock.release()
self.log.debug("add|Releasing lock to job queue.")
self.log.info("Added job %s:%s to queue, details = %s" %
(job.name, job.id, str(job.__dict__)))
return str(job.id)
def addDead(self, job):
""" addDead - add a job to the dead queue.
Called by validateJob when a job validation fails.
Returns -1 on failure and the job id on success
"""
if (not isinstance(job, TangoJob)):
return -1
# Get an id for the new job
self.log.debug("add|Getting next ID")
nextId = self._getNextID()
if (nextId == -1):
self.log.info("add|JobQueue is full")
return -1
job.setId(nextId)
self.log.debug("addDead|Gotten next ID: " + str(job.id))
self.log.info("addDead|Unassigning job %s" % str(job.id))
job.makeUnassigned()
job.retries = 0
self.log.debug("addDead|Acquiring lock to job queue.")
self.queueLock.acquire()
self.log.debug("addDead|Acquired lock to job queue.")
# We add the job into the dead jobs dictionary
self.deadJobs.set(job.id, job)
self.queueLock.release()
self.log.debug("addDead|Released lock to job queue.")
return job.id
def delJob(self, id, deadjob):
""" delJob - Implements delJob() interface call
@param id - The id of the job to remove
@param deadjob - If 0, move the job from the live queue to the
dead queue. If non-zero, remove the job from the dead queue
and discard.
"""
if deadjob == 0:
return self.makeDead(id, "Requested by operator")
else:
status = -1
self.queueLock.acquire()
self.log.debug("delJob| Acquired lock to job queue.")
if id in self.deadJobs:
self.deadJobs.delete(id)
status = 0
self.queueLock.release()
self.log.debug("delJob| Released lock to job queue.")
if status == 0:
self.log.debug("Removed job %s from dead queue" % id)
else:
self.log.error("Job %s not found in dead queue" % id)
return status
def get(self, id):
"""get - retrieve job from live queue
@param id - the id of the job to retrieve
"""
self.queueLock.acquire()
self.log.debug("get| Acquired lock to job queue.")
job = self.liveJobs.get(id)
self.queueLock.release()
self.log.debug("get| Released lock to job queue.")
return job
def assignJob(self, jobId):
""" assignJob - marks a job to be assigned
"""
self.queueLock.acquire()
self.log.debug("assignJob| Acquired lock to job queue.")
job = self.liveJobs.get(jobId)
# Remove the current job from the queue
self.unassignedJobs.remove(int(jobId))
self.log.debug("assignJob| Retrieved job.")
self.log.info("assignJob|Assigning job ID: %s" % str(job.id))
job.makeAssigned()
self.log.debug("assignJob| Releasing lock to job queue.")
self.queueLock.release()
self.log.debug("assignJob| Released lock to job queue.")
def unassignJob(self, jobId):
""" unassignJob - marks a job to be unassigned
Note: We assume here that a job is to be rescheduled or
'retried' when you unassign it. This retry is done by
the worker.
"""
self.queueLock.acquire()
self.log.debug("unassignJob| Acquired lock to job queue.")
# Get the current job
job = self.liveJobs.get(jobId)
# Increment the number of retires
if job.retries is None:
job.retries = 0
else:
job.retries += 1
Config.job_retries += 1
self.log.info("unassignJob|Unassigning job %s" % str(job.id))
job.makeUnassigned()
# Since the assumption is that the job is being retried,
# we simply add the job to the unassigned jobs queue without
# removing anything from it
self.unassignedJobs.put(int(jobId))
self.queueLock.release()
self.log.debug("unassignJob| Released lock to job queue.")
def makeDead(self, id, reason):
""" makeDead - move a job from live queue to dead queue
"""
self.log.info("makeDead| Making dead job ID: " + str(id))
self.queueLock.acquire()
self.log.debug("makeDead| Acquired lock to job queue.")
status = -1
# Check to make sure that the job is in the live jobs queue
if id in self.liveJobs:
self.log.info("makeDead| Found job ID: %s in the live queue" %
(id))
status = 0
job = self.liveJobs.get(id)
self.log.info("Terminated job %s:%s: %s" %
(job.name, job.id, reason))
# Add the job to the dead jobs dictionary
self.deadJobs.set(id, job)
# Remove the job from the live jobs dictionary
self.liveJobs.delete(id)
# Remove the job from the unassigned live jobs queue
self.unassignedJobs.remove(int(id))
job.appendTrace("%s|%s" % (datetime.utcnow().ctime(), reason))
self.queueLock.release()
self.log.debug("makeDead| Released lock to job queue.")
return status
def getInfo(self):
info = {}
info['size'] = len(self.liveJobs.keys())
info['size_deadjobs'] = len(self.deadJobs.keys())
info['size_unassignedjobs'] = self.unassignedJobs.qsize()
return info
def reset(self):
""" reset - resets and clears all the internal dictionaries
and queues
"""
self.liveJobs._clean()
self.deadJobs._clean()
self.unassignedJobs._clean()
def getNextPendingJob(self):
"""Gets the next unassigned live job. Note that this is a
blocking function and we will block till there is an available
job.
"""
# Blocks till the next item is added
id = self.unassignedJobs.get()
self.log.debug("_getNextPendingJob|Acquiring lock to job queue.")
self.queueLock.acquire()
self.log.debug("_getNextPendingJob|Acquired lock to job queue.")
# Get the corresponding job
job = self.liveJobs.get(id)
if job is None:
raise Exception("Cannot find unassigned job in live jobs")
self.log.debug("getNextPendingJob| Releasing lock to job queue.")
self.queueLock.release()
self.log.debug("getNextPendingJob| Released lock to job queue.")
return job
def reuseVM(self, job):
"""Helps a job reuse a vm. This is called if CONFIG.REUSE_VM is
set to true.
"""
# Create a pool if necessary
# This is when there is no existing pool for the vm name required.
if self.preallocator.poolSize(job.vm.name) == 0:
self.preallocator.update(job.vm, Config.POOL_SIZE)
# If the job hasn't been assigned to a worker yet, we try to
# allocate a new vm for this job
if (job.isNotAssigned()):
# Note: This could return None, when all VMs are being used
return self.preallocator.allocVM(job.vm.name)
else:
# In the case where a job is already assigned, it should have
# a vm, and we just return that vm here
if job.vm:
return job.vm
else:
raise Exception("Job assigned without vm")
def destroyRedisPools():
for key in server.preallocator.machines.keys():
print "clean up pool", key
server.preallocator.machines.set(key, [[], TangoQueue(key)])
server.preallocator.machines.get(key)[1].make_empty()
class TestQueue(unittest.TestCase):
def setUp(self):
if Config.USE_REDIS:
__db = redis.StrictRedis(Config.REDIS_HOSTNAME,
Config.REDIS_PORT,
db=0)
__db.flushall()
self.test_entries = [i for i in range(10)]
def addAllToQueue(self):
# Add all items into the queue
for x in self.test_entries:
self.testQueue.put(x)
self.expectedSize += 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
def runQueueTests(self):
self.testQueue = TangoQueue("self.testQueue")
self.expectedSize = 0
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertTrue(self.testQueue.empty())
self.addAllToQueue()
# Test the blocking get
for x in self.test_entries:
item = self.testQueue.get()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
self.addAllToQueue()
# Test the blocking get
for x in self.test_entries:
item = self.testQueue.get_nowait()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
self.addAllToQueue()
# Remove all the even entries
for x in self.test_entries:
if (x % 2 == 0):
self.testQueue.remove(x)
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
# Test that get only returns odd keys in order
for x in self.test_entries:
if (x % 2 == 1):
item = self.testQueue.get_nowait()
self.expectedSize -= 1
self.assertEqual(self.testQueue.qsize(), self.expectedSize)
self.assertEqual(item, x)
def test_nativeQueue(self):
Config.USE_REDIS = False
self.runQueueTests()
def test_remoteQueue(self):
Config.USE_REDIS = True
self.runQueueTests()
