#
#
-# Copyright (C) 2006, 2007 Google Inc.
+# Copyright (C) 2006, 2007, 2008 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# 02110-1301, USA.
-"""Module implementing the job queue handling."""
+"""Module implementing the job queue handling.
+Locking:
+There's a single, large lock in the JobQueue class. It's used by all other
+classes in this module.
+
+"""
+
+import os
import logging
import threading
+import errno
+import re
+import time
+import weakref
from ganeti import constants
+from ganeti import serializer
from ganeti import workerpool
+from ganeti import opcodes
from ganeti import errors
from ganeti import mcpu
+from ganeti import utils
+from ganeti import jstore
+from ganeti import rpc
JOBQUEUE_THREADS = 5
+def TimeStampNow():
+ return utils.SplitTime(time.time())
+
+
class _QueuedOpCode(object):
"""Encasulates an opcode object.
- Access must be synchronized by using an external lock.
+ The 'log' attribute holds the execution log and consists of tuples
+ of the form (log_serial, timestamp, level, message).
"""
def __init__(self, op):
self.input = op
self.status = constants.OP_STATUS_QUEUED
self.result = None
+ self.log = []
+ self.start_timestamp = None
+ self.end_timestamp = None
+
+ @classmethod
+ def Restore(cls, state):
+ obj = _QueuedOpCode.__new__(cls)
+ obj.input = opcodes.OpCode.LoadOpCode(state["input"])
+ obj.status = state["status"]
+ obj.result = state["result"]
+ obj.log = state["log"]
+ obj.start_timestamp = state.get("start_timestamp", None)
+ obj.end_timestamp = state.get("end_timestamp", None)
+ return obj
+
+ def Serialize(self):
+ return {
+ "input": self.input.__getstate__(),
+ "status": self.status,
+ "result": self.result,
+ "log": self.log,
+ "start_timestamp": self.start_timestamp,
+ "end_timestamp": self.end_timestamp,
+ }
class _QueuedJob(object):
"""In-memory job representation.
- This is what we use to track the user-submitted jobs.
+ This is what we use to track the user-submitted jobs. Locking must be taken
+ care of by users of this class.
"""
- def __init__(self, ops, job_id):
+ def __init__(self, queue, job_id, ops):
if not ops:
# TODO
raise Exception("No opcodes")
+ self.queue = queue
self.id = job_id
- self._lock = threading.Lock()
-
- # _ops should not be modified again because we don't acquire the lock
- # to use it.
- self._ops = [_QueuedOpCode(op) for op in ops]
-
- def _GetStatusUnlocked(self):
+ self.ops = [_QueuedOpCode(op) for op in ops]
+ self.run_op_index = -1
+ self.log_serial = 0
+
+ # Condition to wait for changes
+ self.change = threading.Condition(self.queue._lock)
+
+ @classmethod
+ def Restore(cls, queue, state):
+ obj = _QueuedJob.__new__(cls)
+ obj.queue = queue
+ obj.id = state["id"]
+ obj.run_op_index = state["run_op_index"]
+
+ obj.ops = []
+ obj.log_serial = 0
+ for op_state in state["ops"]:
+ op = _QueuedOpCode.Restore(op_state)
+ for log_entry in op.log:
+ obj.log_serial = max(obj.log_serial, log_entry[0])
+ obj.ops.append(op)
+
+ # Condition to wait for changes
+ obj.change = threading.Condition(obj.queue._lock)
+
+ return obj
+
+ def Serialize(self):
+ return {
+ "id": self.id,
+ "ops": [op.Serialize() for op in self.ops],
+ "run_op_index": self.run_op_index,
+ }
+
+ def CalcStatus(self):
status = constants.JOB_STATUS_QUEUED
all_success = True
- for op in self._ops:
+ for op in self.ops:
if op.status == constants.OP_STATUS_SUCCESS:
continue
if op.status == constants.OP_STATUS_QUEUED:
pass
- elif op.status == constants.OP_STATUS_ERROR:
- status = constants.JOB_STATUS_ERROR
elif op.status == constants.OP_STATUS_RUNNING:
status = constants.JOB_STATUS_RUNNING
+ elif op.status == constants.OP_STATUS_ERROR:
+ status = constants.JOB_STATUS_ERROR
+ # The whole job fails if one opcode failed
+ break
+ elif op.status == constants.OP_STATUS_CANCELED:
+ status = constants.OP_STATUS_CANCELED
+ break
if all_success:
status = constants.JOB_STATUS_SUCCESS
return status
- def GetStatus(self):
- self._lock.acquire()
- try:
- return self._GetStatusUnlocked()
- finally:
- self._lock.release()
+ def GetLogEntries(self, newer_than):
+ if newer_than is None:
+ serial = -1
+ else:
+ serial = newer_than
- def Run(self, proc):
- """Job executor.
+ entries = []
+ for op in self.ops:
+ entries.extend(filter(lambda entry: entry[0] > newer_than, op.log))
- This functions processes a this job in the context of given processor
- instance.
+ return entries
- Args:
- - proc: Ganeti Processor to run the job with
+
+class _JobQueueWorker(workerpool.BaseWorker):
+ def RunTask(self, job):
+ """Job executor.
+
+ This functions processes a job. It is closely tied to the _QueuedJob and
+ _QueuedOpCode classes.
"""
+ logging.debug("Worker %s processing job %s",
+ self.worker_id, job.id)
+ proc = mcpu.Processor(self.pool.queue.context)
+ queue = job.queue
try:
- count = len(self._ops)
- for idx, op in enumerate(self._ops):
- try:
- self._lock.acquire()
+ try:
+ count = len(job.ops)
+ for idx, op in enumerate(job.ops):
try:
logging.debug("Op %s/%s: Starting %s", idx + 1, count, op)
- op.status = constants.OP_STATUS_RUNNING
- finally:
- self._lock.release()
- result = proc.ExecOpCode(op.input)
+ queue.acquire()
+ try:
+ job.run_op_index = idx
+ op.status = constants.OP_STATUS_RUNNING
+ op.result = None
+ op.start_timestamp = TimeStampNow()
+ queue.UpdateJobUnlocked(job)
+
+ input_opcode = op.input
+ finally:
+ queue.release()
+
+ def _Log(*args):
+ """Append a log entry.
+
+ """
+ assert len(args) < 3
+
+ if len(args) == 1:
+ log_type = constants.ELOG_MESSAGE
+ log_msg = args[0]
+ else:
+ log_type, log_msg = args
+
+ # The time is split to make serialization easier and not lose
+ # precision.
+ timestamp = utils.SplitTime(time.time())
+
+ queue.acquire()
+ try:
+ job.log_serial += 1
+ op.log.append((job.log_serial, timestamp, log_type, log_msg))
+
+ job.change.notifyAll()
+ finally:
+ queue.release()
+
+ # Make sure not to hold lock while _Log is called
+ result = proc.ExecOpCode(input_opcode, _Log)
+
+ queue.acquire()
+ try:
+ op.status = constants.OP_STATUS_SUCCESS
+ op.result = result
+ op.end_timestamp = TimeStampNow()
+ queue.UpdateJobUnlocked(job)
+ finally:
+ queue.release()
- self._lock.acquire()
- try:
logging.debug("Op %s/%s: Successfully finished %s",
idx + 1, count, op)
- op.status = constants.OP_STATUS_SUCCESS
- op.result = result
- finally:
- self._lock.release()
- except Exception, err:
- self._lock.acquire()
- try:
- logging.debug("Op %s/%s: Error in %s", idx + 1, count, op)
- op.status = constants.OP_STATUS_ERROR
- op.result = str(err)
- finally:
- self._lock.release()
- raise
-
- except errors.GenericError, err:
- logging.error("ganeti exception %s", exc_info=err)
- except Exception, err:
- logging.error("unhandled exception %s", exc_info=err)
- except:
- logging.error("unhandled unknown exception %s", exc_info=err)
-
-
-class _JobQueueWorker(workerpool.BaseWorker):
- def RunTask(self, job):
- logging.debug("Worker %s processing job %s",
- self.worker_id, job.id)
- # TODO: feedback function
- proc = mcpu.Processor(self.pool.context, feedback=lambda x: None)
- try:
- job.Run(proc)
+ except Exception, err:
+ queue.acquire()
+ try:
+ try:
+ op.status = constants.OP_STATUS_ERROR
+ op.result = str(err)
+ op.end_timestamp = TimeStampNow()
+ logging.debug("Op %s/%s: Error in %s", idx + 1, count, op)
+ finally:
+ queue.UpdateJobUnlocked(job)
+ finally:
+ queue.release()
+ raise
+
+ except errors.GenericError, err:
+ logging.exception("Ganeti exception")
+ except:
+ logging.exception("Unhandled exception")
finally:
+ queue.acquire()
+ try:
+ try:
+ job.run_op_idx = -1
+ queue.UpdateJobUnlocked(job)
+ finally:
+ job_id = job.id
+ status = job.CalcStatus()
+ finally:
+ queue.release()
logging.debug("Worker %s finished job %s, status = %s",
- self.worker_id, job.id, job.GetStatus())
+ self.worker_id, job_id, status)
class _JobQueueWorkerPool(workerpool.WorkerPool):
- def __init__(self, context):
+ def __init__(self, queue):
super(_JobQueueWorkerPool, self).__init__(JOBQUEUE_THREADS,
_JobQueueWorker)
- self.context = context
+ self.queue = queue
+
+
+class JobQueue(object):
+ _RE_JOB_FILE = re.compile(r"^job-(%s)$" % constants.JOB_ID_TEMPLATE)
+ def _RequireOpenQueue(fn):
+ """Decorator for "public" functions.
-class JobQueue:
- """The job queue.
+ This function should be used for all "public" functions. That is, functions
+ usually called from other classes.
+
+ Important: Use this decorator only after utils.LockedMethod!
+
+ Example:
+ @utils.LockedMethod
+ @_RequireOpenQueue
+ def Example(self):
+ pass
+
+ """
+ def wrapper(self, *args, **kwargs):
+ assert self._queue_lock is not None, "Queue should be open"
+ return fn(self, *args, **kwargs)
+ return wrapper
- """
def __init__(self, context):
+ self.context = context
+ self._memcache = weakref.WeakValueDictionary()
+ self._my_hostname = utils.HostInfo().name
+
+ # Locking
self._lock = threading.Lock()
- self._last_job_id = 0
- self._jobs = {}
- self._wpool = _JobQueueWorkerPool(context)
+ self.acquire = self._lock.acquire
+ self.release = self._lock.release
+
+ # Initialize
+ self._queue_lock = jstore.InitAndVerifyQueue(must_lock=True)
+
+ # Read serial file
+ self._last_serial = jstore.ReadSerial()
+ assert self._last_serial is not None, ("Serial file was modified between"
+ " check in jstore and here")
+
+ # Get initial list of nodes
+ self._nodes = set(self.context.cfg.GetNodeList())
+
+ # Remove master node
+ try:
+ self._nodes.remove(self._my_hostname)
+ except ValueError:
+ pass
+
+ # TODO: Check consistency across nodes
+
+ # Setup worker pool
+ self._wpool = _JobQueueWorkerPool(self)
+
+ # We need to lock here because WorkerPool.AddTask() may start a job while
+ # we're still doing our work.
+ self.acquire()
+ try:
+ for job in self._GetJobsUnlocked(None):
+ status = job.CalcStatus()
+
+ if status in (constants.JOB_STATUS_QUEUED, ):
+ self._wpool.AddTask(job)
+
+ elif status in (constants.JOB_STATUS_RUNNING, ):
+ logging.warning("Unfinished job %s found: %s", job.id, job)
+ try:
+ for op in job.ops:
+ op.status = constants.OP_STATUS_ERROR
+ op.result = "Unclean master daemon shutdown"
+ finally:
+ self.UpdateJobUnlocked(job)
+ finally:
+ self.release()
+
+ @utils.LockedMethod
+ @_RequireOpenQueue
+ def AddNode(self, node_name):
+ assert node_name != self._my_hostname
+
+ # Clean queue directory on added node
+ rpc.call_jobqueue_purge(node_name)
+
+ # Upload the whole queue excluding archived jobs
+ files = [self._GetJobPath(job_id) for job_id in self._GetJobIDsUnlocked()]
- def _NewJobIdUnlocked(self):
+ # Upload current serial file
+ files.append(constants.JOB_QUEUE_SERIAL_FILE)
+
+ for file_name in files:
+ # Read file content
+ fd = open(file_name, "r")
+ try:
+ content = fd.read()
+ finally:
+ fd.close()
+
+ result = rpc.call_jobqueue_update([node_name], file_name, content)
+ if not result[node_name]:
+ logging.error("Failed to upload %s to %s", file_name, node_name)
+
+ self._nodes.add(node_name)
+
+ @utils.LockedMethod
+ @_RequireOpenQueue
+ def RemoveNode(self, node_name):
+ try:
+ # The queue is removed by the "leave node" RPC call.
+ self._nodes.remove(node_name)
+ except KeyError:
+ pass
+
+ def _CheckRpcResult(self, result, nodes, failmsg):
+ failed = []
+ success = []
+
+ for node in nodes:
+ if result[node]:
+ success.append(node)
+ else:
+ failed.append(node)
+
+ if failed:
+ logging.error("%s failed on %s", failmsg, ", ".join(failed))
+
+ # +1 for the master node
+ if (len(success) + 1) < len(failed):
+ # TODO: Handle failing nodes
+ logging.error("More than half of the nodes failed")
+
+ def _WriteAndReplicateFileUnlocked(self, file_name, data):
+ """Writes a file locally and then replicates it to all nodes.
+
+ """
+ utils.WriteFile(file_name, data=data)
+
+ result = rpc.call_jobqueue_update(self._nodes, file_name, data)
+ self._CheckRpcResult(result, self._nodes,
+ "Updating %s" % file_name)
+
+ def _RenameFileUnlocked(self, old, new):
+ os.rename(old, new)
+
+ result = rpc.call_jobqueue_rename(self._nodes, old, new)
+ self._CheckRpcResult(result, self._nodes,
+ "Moving %s to %s" % (old, new))
+
+ def _FormatJobID(self, job_id):
+ if not isinstance(job_id, (int, long)):
+ raise errors.ProgrammerError("Job ID '%s' not numeric" % job_id)
+ if job_id < 0:
+ raise errors.ProgrammerError("Job ID %s is negative" % job_id)
+
+ return str(job_id)
+
+ def _NewSerialUnlocked(self):
"""Generates a new job identifier.
+ Job identifiers are unique during the lifetime of a cluster.
+
Returns: A string representing the job identifier.
"""
- self._last_job_id += 1
- return str(self._last_job_id)
+ # New number
+ serial = self._last_serial + 1
+
+ # Write to file
+ self._WriteAndReplicateFileUnlocked(constants.JOB_QUEUE_SERIAL_FILE,
+ "%s\n" % serial)
+
+ # Keep it only if we were able to write the file
+ self._last_serial = serial
+
+ return self._FormatJobID(serial)
+
+ @staticmethod
+ def _GetJobPath(job_id):
+ return os.path.join(constants.QUEUE_DIR, "job-%s" % job_id)
+
+ @staticmethod
+ def _GetArchivedJobPath(job_id):
+ return os.path.join(constants.JOB_QUEUE_ARCHIVE_DIR, "job-%s" % job_id)
+
+ @classmethod
+ def _ExtractJobID(cls, name):
+ m = cls._RE_JOB_FILE.match(name)
+ if m:
+ return m.group(1)
+ else:
+ return None
+
+ def _GetJobIDsUnlocked(self, archived=False):
+ """Return all known job IDs.
+
+ If the parameter archived is True, archived jobs IDs will be
+ included. Currently this argument is unused.
+
+ The method only looks at disk because it's a requirement that all
+ jobs are present on disk (so in the _memcache we don't have any
+ extra IDs).
+
+ """
+ jlist = [self._ExtractJobID(name) for name in self._ListJobFiles()]
+ jlist.sort()
+ return jlist
+
+ def _ListJobFiles(self):
+ return [name for name in utils.ListVisibleFiles(constants.QUEUE_DIR)
+ if self._RE_JOB_FILE.match(name)]
+
+ def _LoadJobUnlocked(self, job_id):
+ job = self._memcache.get(job_id, None)
+ if job:
+ logging.debug("Found job %s in memcache", job_id)
+ return job
+
+ filepath = self._GetJobPath(job_id)
+ logging.debug("Loading job from %s", filepath)
+ try:
+ fd = open(filepath, "r")
+ except IOError, err:
+ if err.errno in (errno.ENOENT, ):
+ return None
+ raise
+ try:
+ data = serializer.LoadJson(fd.read())
+ finally:
+ fd.close()
+
+ job = _QueuedJob.Restore(self, data)
+ self._memcache[job_id] = job
+ logging.debug("Added job %s to the cache", job_id)
+ return job
+ def _GetJobsUnlocked(self, job_ids):
+ if not job_ids:
+ job_ids = self._GetJobIDsUnlocked()
+
+ return [self._LoadJobUnlocked(job_id) for job_id in job_ids]
+
+ @utils.LockedMethod
+ @_RequireOpenQueue
def SubmitJob(self, ops):
- """Add a new job to the queue.
+ """Create and store a new job.
This enters the job into our job queue and also puts it on the new
queue, in order for it to be picked up by the queue processors.
- Args:
- - ops: Sequence of opcodes
+ @type ops: list
+ @param ops: The list of OpCodes that will become the new job.
"""
# Get job identifier
- self._lock.acquire()
- try:
- job_id = self._NewJobIdUnlocked()
- finally:
- self._lock.release()
+ job_id = self._NewSerialUnlocked()
+ job = _QueuedJob(self, job_id, ops)
- job = _QueuedJob(ops, job_id)
+ # Write to disk
+ self.UpdateJobUnlocked(job)
- # Add it to our internal queue
- self._lock.acquire()
- try:
- self._jobs[job_id] = job
- finally:
- self._lock.release()
+ logging.debug("Adding new job %s to the cache", job_id)
+ self._memcache[job_id] = job
# Add to worker pool
self._wpool.AddTask(job)
- return job_id
+ return job.id
+
+ @_RequireOpenQueue
+ def UpdateJobUnlocked(self, job):
+ filename = self._GetJobPath(job.id)
+ data = serializer.DumpJson(job.Serialize(), indent=False)
+ logging.debug("Writing job %s to %s", job.id, filename)
+ self._WriteAndReplicateFileUnlocked(filename, data)
+
+ # Notify waiters about potential changes
+ job.change.notifyAll()
+
+ @utils.LockedMethod
+ @_RequireOpenQueue
+ def WaitForJobChanges(self, job_id, fields, prev_job_info, prev_log_serial,
+ timeout):
+ """Waits for changes in a job.
+
+ @type job_id: string
+ @param job_id: Job identifier
+ @type fields: list of strings
+ @param fields: Which fields to check for changes
+ @type prev_job_info: list or None
+ @param prev_job_info: Last job information returned
+ @type prev_log_serial: int
+ @param prev_log_serial: Last job message serial number
+ @type timeout: float
+ @param timeout: maximum time to wait
+
+ """
+ logging.debug("Waiting for changes in job %s", job_id)
+ end_time = time.time() + timeout
+ while True:
+ delta_time = end_time - time.time()
+ if delta_time < 0:
+ return constants.JOB_NOTCHANGED
+
+ job = self._LoadJobUnlocked(job_id)
+ if not job:
+ logging.debug("Job %s not found", job_id)
+ break
+
+ status = job.CalcStatus()
+ job_info = self._GetJobInfoUnlocked(job, fields)
+ log_entries = job.GetLogEntries(prev_log_serial)
+
+ # Serializing and deserializing data can cause type changes (e.g. from
+ # tuple to list) or precision loss. We're doing it here so that we get
+ # the same modifications as the data received from the client. Without
+ # this, the comparison afterwards might fail without the data being
+ # significantly different.
+ job_info = serializer.LoadJson(serializer.DumpJson(job_info))
+ log_entries = serializer.LoadJson(serializer.DumpJson(log_entries))
+
+ if status not in (constants.JOB_STATUS_QUEUED,
+ constants.JOB_STATUS_RUNNING):
+ # Don't even try to wait if the job is no longer running, there will be
+ # no changes.
+ break
+
+ if (prev_job_info != job_info or
+ (log_entries and prev_log_serial != log_entries[0][0])):
+ break
+
+ logging.debug("Waiting again")
+
+ # Release the queue lock while waiting
+ job.change.wait(delta_time)
+
+ logging.debug("Job %s changed", job_id)
+
+ return (job_info, log_entries)
+
+ @utils.LockedMethod
+ @_RequireOpenQueue
+ def CancelJob(self, job_id):
+ """Cancels a job.
+
+ @type job_id: string
+ @param job_id: Job ID of job to be cancelled.
+
+ """
+ logging.debug("Cancelling job %s", job_id)
+
+ job = self._LoadJobUnlocked(job_id)
+ if not job:
+ logging.debug("Job %s not found", job_id)
+ return
+
+ if job.CalcStatus() not in (constants.JOB_STATUS_QUEUED,):
+ logging.debug("Job %s is no longer in the queue", job.id)
+ return
+
+ try:
+ for op in job.ops:
+ op.status = constants.OP_STATUS_ERROR
+ op.result = "Job cancelled by request"
+ finally:
+ self.UpdateJobUnlocked(job)
+ @utils.LockedMethod
+ @_RequireOpenQueue
def ArchiveJob(self, job_id):
- raise NotImplementedError()
+ """Archives a job.
- def CancelJob(self, job_id):
- raise NotImplementedError()
+ @type job_id: string
+ @param job_id: Job ID of job to be archived.
+
+ """
+ logging.debug("Archiving job %s", job_id)
+
+ job = self._LoadJobUnlocked(job_id)
+ if not job:
+ logging.debug("Job %s not found", job_id)
+ return
+
+ if job.CalcStatus() not in (constants.JOB_STATUS_CANCELED,
+ constants.JOB_STATUS_SUCCESS,
+ constants.JOB_STATUS_ERROR):
+ logging.debug("Job %s is not yet done", job.id)
+ return
+
+ old = self._GetJobPath(job.id)
+ new = self._GetArchivedJobPath(job.id)
- def _GetJobInfo(self, job, fields):
+ self._RenameFileUnlocked(old, new)
+
+ logging.debug("Successfully archived job %s", job.id)
+
+ def _GetJobInfoUnlocked(self, job, fields):
row = []
for fname in fields:
if fname == "id":
row.append(job.id)
elif fname == "status":
- row.append(job.GetStatus())
- elif fname == "result":
- # TODO
- row.append(map(lambda op: op.result, job._ops))
+ row.append(job.CalcStatus())
+ elif fname == "ops":
+ row.append([op.input.__getstate__() for op in job.ops])
+ elif fname == "opresult":
+ row.append([op.result for op in job.ops])
+ elif fname == "opstatus":
+ row.append([op.status for op in job.ops])
else:
raise errors.OpExecError("Invalid job query field '%s'" % fname)
return row
+ @utils.LockedMethod
+ @_RequireOpenQueue
def QueryJobs(self, job_ids, fields):
"""Returns a list of jobs in queue.
- fields: Names of fields to return
"""
- self._lock.acquire()
- try:
- if not job_ids:
- job_ids = self._jobs.keys()
-
- # TODO: define sort order?
- job_ids.sort()
+ jobs = []
- jobs = []
-
- for job_id in job_ids:
- job = self._jobs.get(job_id, None)
- if job is None:
- jobs.append(None)
- else:
- jobs.append(self._GetJobInfo(job, fields))
+ for job in self._GetJobsUnlocked(job_ids):
+ if job is None:
+ jobs.append(None)
+ else:
+ jobs.append(self._GetJobInfoUnlocked(job, fields))
- return jobs
- finally:
- self._lock.release()
+ return jobs
+ @utils.LockedMethod
+ @_RequireOpenQueue
def Shutdown(self):
"""Stops the job queue.
"""
self._wpool.TerminateWorkers()
+
+ self._queue_lock.Close()
+ self._queue_lock = None
projects / ganeti-local / blobdiff