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Iustin Pop authored
Currently we only log "Error in opcode ...", but we don't log the error itself. This is not good for debugging. Reviewed-by: ultrotter
0f6be82a
jqueue.py 37.91 KiB
#
#
# 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
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.
"""Module implementing the job queue handling.
Locking: there's a single, large lock in the L{JobQueue} class. It's
used by all other classes in this module.
@var JOBQUEUE_THREADS: the number of worker threads we start for
processing jobs
"""
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 = 25
JOBS_PER_ARCHIVE_DIRECTORY = 10000
class CancelJob(Exception):
"""Special exception to cancel a job.
"""
def TimeStampNow():
"""Returns the current timestamp.
@rtype: tuple
@return: the current time in the (seconds, microseconds) format
"""
return utils.SplitTime(time.time())
class _QueuedOpCode(object):
"""Encasulates an opcode object.
@ivar log: holds the execution log and consists of tuples
of the form C{(log_serial, timestamp, level, message)}
@ivar input: the OpCode we encapsulate
@ivar status: the current status
@ivar result: the result of the LU execution
@ivar start_timestamp: timestamp for the start of the execution
@ivar stop_timestamp: timestamp for the end of the execution
"""
def __init__(self, op):
"""Constructor for the _QuededOpCode.
@type op: L{opcodes.OpCode}
@param op: the opcode we encapsulate
"""
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):
"""Restore the _QueuedOpCode from the serialized form.
@type state: dict
@param state: the serialized state
@rtype: _QueuedOpCode
@return: a new _QueuedOpCode instance
"""
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):
"""Serializes this _QueuedOpCode.
@rtype: dict
@return: the dictionary holding the serialized state
"""
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. Locking must
be taken care of by users of this class.
@type queue: L{JobQueue}
@ivar queue: the parent queue
@ivar id: the job ID
@type ops: list
@ivar ops: the list of _QueuedOpCode that constitute the job
@type run_op_index: int
@ivar run_op_index: the currently executing opcode, or -1 if
we didn't yet start executing
@type log_serial: int
@ivar log_serial: holds the index for the next log entry
@ivar received_timestamp: the timestamp for when the job was received
@ivar start_timestmap: the timestamp for start of execution
@ivar end_timestamp: the timestamp for end of execution
@ivar change: a Condition variable we use for waiting for job changes
"""
def __init__(self, queue, job_id, ops):
"""Constructor for the _QueuedJob.
@type queue: L{JobQueue}
@param queue: our parent queue
@type job_id: job_id
@param job_id: our job id
@type ops: list
@param ops: the list of opcodes we hold, which will be encapsulated
in _QueuedOpCodes
"""
if not ops:
# TODO: use a better exception
raise Exception("No opcodes")
self.queue = queue
self.id = job_id
self.ops = [_QueuedOpCode(op) for op in ops]
self.run_op_index = -1
self.log_serial = 0
self.received_timestamp = TimeStampNow()
self.start_timestamp = None
self.end_timestamp = None
# Condition to wait for changes
self.change = threading.Condition(self.queue._lock)
@classmethod
def Restore(cls, queue, state):
"""Restore a _QueuedJob from serialized state:
@type queue: L{JobQueue}
@param queue: to which queue the restored job belongs
@type state: dict
@param state: the serialized state
@rtype: _JobQueue
@return: the restored _JobQueue instance
"""
obj = _QueuedJob.__new__(cls)
obj.queue = queue
obj.id = state["id"]
obj.run_op_index = state["run_op_index"]
obj.received_timestamp = state.get("received_timestamp", None)
obj.start_timestamp = state.get("start_timestamp", None)
obj.end_timestamp = state.get("end_timestamp", None)
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):
"""Serialize the _JobQueue instance.
@rtype: dict
@return: the serialized state
"""
return {
"id": self.id,
"ops": [op.Serialize() for op in self.ops],
"run_op_index": self.run_op_index,
"start_timestamp": self.start_timestamp,
"end_timestamp": self.end_timestamp,
"received_timestamp": self.received_timestamp,
}
def CalcStatus(self):
"""Compute the status of this job.
This function iterates over all the _QueuedOpCodes in the job and
based on their status, computes the job status.
The algorithm is:
- if we find a cancelled, or finished with error, the job
status will be the same
- otherwise, the last opcode with the status one of:
- waitlock
- canceling
- running
will determine the job status
- otherwise, it means either all opcodes are queued, or success,
and the job status will be the same
@return: the job status
"""
status = constants.JOB_STATUS_QUEUED
all_success = True
for op in self.ops:
if op.status == constants.OP_STATUS_SUCCESS:
continue
all_success = False
if op.status == constants.OP_STATUS_QUEUED:
pass
elif op.status == constants.OP_STATUS_WAITLOCK:
status = constants.JOB_STATUS_WAITLOCK
elif op.status == constants.OP_STATUS_RUNNING:
status = constants.JOB_STATUS_RUNNING
elif op.status == constants.OP_STATUS_CANCELING:
status = constants.JOB_STATUS_CANCELING
break
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 GetLogEntries(self, newer_than):
"""Selectively returns the log entries.
@type newer_than: None or int
@param newer_than: if this is None, return all log enties,
otherwise return only the log entries with serial higher
than this value
@rtype: list
@return: the list of the log entries selected
"""
if newer_than is None:
serial = -1
else:
serial = newer_than
entries = []
for op in self.ops:
entries.extend(filter(lambda entry: entry[0] > serial, op.log))
return entries
class _JobQueueWorker(workerpool.BaseWorker):
"""The actual job workers.
"""
def _NotifyStart(self):
"""Mark the opcode as running, not lock-waiting.
This is called from the mcpu code as a notifier function, when the
LU is finally about to start the Exec() method. Of course, to have
end-user visible results, the opcode must be initially (before
calling into Processor.ExecOpCode) set to OP_STATUS_WAITLOCK.
"""
assert self.queue, "Queue attribute is missing"
assert self.opcode, "Opcode attribute is missing"
self.queue.acquire()
try:
assert self.opcode.status in (constants.OP_STATUS_WAITLOCK,
constants.OP_STATUS_CANCELING)
# Cancel here if we were asked to
if self.opcode.status == constants.OP_STATUS_CANCELING:
raise CancelJob()
self.opcode.status = constants.OP_STATUS_RUNNING
finally:
self.queue.release()
def RunTask(self, job):
"""Job executor.
This functions processes a job. It is closely tied to the _QueuedJob and
_QueuedOpCode classes.
@type job: L{_QueuedJob}
@param job: the job to be processed
"""
logging.info("Worker %s processing job %s",
self.worker_id, job.id)
proc = mcpu.Processor(self.pool.queue.context)
self.queue = queue = job.queue
try:
try:
count = len(job.ops)
for idx, op in enumerate(job.ops):
op_summary = op.input.Summary()
try:
logging.info("Op %s/%s: Starting opcode %s", idx + 1, count,
op_summary)
queue.acquire()
try:
if op.status == constants.OP_STATUS_CANCELED:
raise CancelJob()
assert op.status == constants.OP_STATUS_QUEUED
job.run_op_index = idx
op.status = constants.OP_STATUS_WAITLOCK
op.result = None
op.start_timestamp = TimeStampNow()
if idx == 0: # first opcode
job.start_timestamp = op.start_timestamp
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
self.opcode = op
result = proc.ExecOpCode(input_opcode, _Log, self._NotifyStart)
queue.acquire()
try:
op.status = constants.OP_STATUS_SUCCESS
op.result = result
op.end_timestamp = TimeStampNow()
queue.UpdateJobUnlocked(job)
finally:
queue.release()
logging.info("Op %s/%s: Successfully finished opcode %s",
idx + 1, count, op_summary)
except CancelJob:
# Will be handled further up
raise
except Exception, err:
queue.acquire()
try:
try:
op.status = constants.OP_STATUS_ERROR
op.result = str(err)
op.end_timestamp = TimeStampNow()
logging.info("Op %s/%s: Error in opcode %s: %s",
idx + 1, count, op_summary, err)
finally:
queue.UpdateJobUnlocked(job)
finally:
queue.release()
raise
except CancelJob:
queue.acquire()
try:
queue.CancelJobUnlocked(job)
finally:
queue.release()
except errors.GenericError, err:
logging.exception("Ganeti exception")
except:
logging.exception("Unhandled exception")
finally:
queue.acquire()
try:
try:
job.run_op_idx = -1
job.end_timestamp = TimeStampNow()
queue.UpdateJobUnlocked(job)
finally:
job_id = job.id
status = job.CalcStatus()
finally:
queue.release()
logging.info("Worker %s finished job %s, status = %s",
self.worker_id, job_id, status)
class _JobQueueWorkerPool(workerpool.WorkerPool):
"""Simple class implementing a job-processing workerpool.
"""
def __init__(self, queue):
super(_JobQueueWorkerPool, self).__init__(JOBQUEUE_THREADS,
_JobQueueWorker)
self.queue = queue
class JobQueue(object):
"""Quue used to manaage the jobs.
@cvar _RE_JOB_FILE: regex matching the valid job file names
"""
_RE_JOB_FILE = re.compile(r"^job-(%s)$" % constants.JOB_ID_TEMPLATE)
def _RequireOpenQueue(fn):
"""Decorator for "public" functions.
This function should be used for all 'public' functions. That is,
functions usually called from other classes.
@warning: 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):
"""Constructor for JobQueue.
The constructor will initialize the job queue object and then
start loading the current jobs from disk, either for starting them
(if they were queue) or for aborting them (if they were already
running).
@type context: GanetiContext
@param context: the context object for access to the configuration
data and other ganeti objects
"""
self.context = context
self._memcache = weakref.WeakValueDictionary()
self._my_hostname = utils.HostInfo().name
# Locking
self._lock = threading.Lock()
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 = dict((n.name, n.primary_ip)
for n in self.context.cfg.GetAllNodesInfo().values()
if n.master_candidate)
# Remove master node
try:
del self._nodes[self._my_hostname]
except KeyError:
pass
# TODO: Check consistency across nodes
# Setup worker pool
self._wpool = _JobQueueWorkerPool(self)
try:
# We need to lock here because WorkerPool.AddTask() may start a job while
# we're still doing our work.
self.acquire()
try:
logging.info("Inspecting job queue")
all_job_ids = self._GetJobIDsUnlocked()
jobs_count = len(all_job_ids)
lastinfo = time.time()
for idx, job_id in enumerate(all_job_ids):
# Give an update every 1000 jobs or 10 seconds
if (idx % 1000 == 0 or time.time() >= (lastinfo + 10.0) or
idx == (jobs_count - 1)):
logging.info("Job queue inspection: %d/%d (%0.1f %%)",
idx, jobs_count - 1, 100.0 * (idx + 1) / jobs_count)
lastinfo = time.time()
job = self._LoadJobUnlocked(job_id)
# a failure in loading the job can cause 'None' to be returned
if job is None:
continue
status = job.CalcStatus()
if status in (constants.JOB_STATUS_QUEUED, ):
self._wpool.AddTask(job)
elif status in (constants.JOB_STATUS_RUNNING,
constants.JOB_STATUS_WAITLOCK,
constants.JOB_STATUS_CANCELING):
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)
logging.info("Job queue inspection finished")
finally:
self.release()
except:
self._wpool.TerminateWorkers()
raise
@utils.LockedMethod
@_RequireOpenQueue
def AddNode(self, node):
"""Register a new node with the queue.
@type node: L{objects.Node}
@param node: the node object to be added
"""
node_name = node.name
assert node_name != self._my_hostname
# Clean queue directory on added node
rpc.RpcRunner.call_jobqueue_purge(node_name)
if not node.master_candidate:
# remove if existing, ignoring errors
self._nodes.pop(node_name, None)
# and skip the replication of the job ids
return
# Upload the whole queue excluding archived jobs
files = [self._GetJobPath(job_id) for job_id in self._GetJobIDsUnlocked()]
# 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.RpcRunner.call_jobqueue_update([node_name],
[node.primary_ip],
file_name, content)
if not result[node_name]:
logging.error("Failed to upload %s to %s", file_name, node_name)
self._nodes[node_name] = node.primary_ip
@utils.LockedMethod
@_RequireOpenQueue
def RemoveNode(self, node_name):
"""Callback called when removing nodes from the cluster.
@type node_name: str
@param node_name: the name of the node to remove
"""
try:
# The queue is removed by the "leave node" RPC call.
del self._nodes[node_name]
except KeyError:
pass
def _CheckRpcResult(self, result, nodes, failmsg):
"""Verifies the status of an RPC call.
Since we aim to keep consistency should this node (the current
master) fail, we will log errors if our rpc fail, and especially
log the case when more than half of the nodes failes.
@param result: the data as returned from the rpc call
@type nodes: list
@param nodes: the list of nodes we made the call to
@type failmsg: str
@param failmsg: the identifier to be used for logging
"""
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 _GetNodeIp(self):
"""Helper for returning the node name/ip list.
@rtype: (list, list)
@return: a tuple of two lists, the first one with the node
names and the second one with the node addresses
"""
name_list = self._nodes.keys()
addr_list = [self._nodes[name] for name in name_list]
return name_list, addr_list
def _WriteAndReplicateFileUnlocked(self, file_name, data):
"""Writes a file locally and then replicates it to all nodes.
This function will replace the contents of a file on the local
node and then replicate it to all the other nodes we have.
@type file_name: str
@param file_name: the path of the file to be replicated
@type data: str
@param data: the new contents of the file
"""
utils.WriteFile(file_name, data=data)
names, addrs = self._GetNodeIp()
result = rpc.RpcRunner.call_jobqueue_update(names, addrs, file_name, data)
self._CheckRpcResult(result, self._nodes,
"Updating %s" % file_name)
def _RenameFilesUnlocked(self, rename):
"""Renames a file locally and then replicate the change.
This function will rename a file in the local queue directory
and then replicate this rename to all the other nodes we have.
@type rename: list of (old, new)
@param rename: List containing tuples mapping old to new names
"""
# Rename them locally
for old, new in rename:
utils.RenameFile(old, new, mkdir=True)
# ... and on all nodes
names, addrs = self._GetNodeIp()
result = rpc.RpcRunner.call_jobqueue_rename(names, addrs, rename)
self._CheckRpcResult(result, self._nodes, "Renaming files (%r)" % rename)
def _FormatJobID(self, job_id):
"""Convert a job ID to string format.
Currently this just does C{str(job_id)} after performing some
checks, but if we want to change the job id format this will
abstract this change.
@type job_id: int or long
@param job_id: the numeric job id
@rtype: str
@return: the formatted 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)
@classmethod
def _GetArchiveDirectory(cls, job_id):
"""Returns the archive directory for a job.
@type job_id: str
@param job_id: Job identifier
@rtype: str
@return: Directory name
"""
return str(int(job_id) / JOBS_PER_ARCHIVE_DIRECTORY)
def _NewSerialUnlocked(self):
"""Generates a new job identifier.
Job identifiers are unique during the lifetime of a cluster.
@rtype: str
@return: a string representing the job identifier.
"""
# 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):
"""Returns the job file for a given job id.
@type job_id: str
@param job_id: the job identifier
@rtype: str
@return: the path to the job file
"""
return os.path.join(constants.QUEUE_DIR, "job-%s" % job_id)
@classmethod
def _GetArchivedJobPath(cls, job_id):
"""Returns the archived job file for a give job id.
@type job_id: str
@param job_id: the job identifier
@rtype: str
@return: the path to the archived job file
"""
path = "%s/job-%s" % (cls._GetArchiveDirectory(job_id), job_id)
return os.path.join(constants.JOB_QUEUE_ARCHIVE_DIR, path)
@classmethod
def _ExtractJobID(cls, name):
"""Extract the job id from a filename.
@type name: str
@param name: the job filename
@rtype: job id or None
@return: the job id corresponding to the given filename,
or None if the filename does not represent a valid
job file
"""
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).
@rtype: list
@return: the list of job IDs
"""
jlist = [self._ExtractJobID(name) for name in self._ListJobFiles()]
jlist = utils.NiceSort(jlist)
return jlist
def _ListJobFiles(self):
"""Returns the list of current job files.
@rtype: list
@return: the list of job file names
"""
return [name for name in utils.ListVisibleFiles(constants.QUEUE_DIR)
if self._RE_JOB_FILE.match(name)]
def _LoadJobUnlocked(self, job_id):
"""Loads a job from the disk or memory.
Given a job id, this will return the cached job object if
existing, or try to load the job from the disk. If loading from
disk, it will also add the job to the cache.
@param job_id: the job id
@rtype: L{_QueuedJob} or None
@return: either None or the job object
"""
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()
try:
job = _QueuedJob.Restore(self, data)
except Exception, err:
new_path = self._GetArchivedJobPath(job_id)
if filepath == new_path:
# job already archived (future case)
logging.exception("Can't parse job %s", job_id)
else:
# non-archived case
logging.exception("Can't parse job %s, will archive.", job_id)
self._RenameFilesUnlocked([(filepath, new_path)])
return None
self._memcache[job_id] = job
logging.debug("Added job %s to the cache", job_id)
return job
def _GetJobsUnlocked(self, job_ids):
"""Return a list of jobs based on their IDs.
@type job_ids: list
@param job_ids: either an empty list (meaning all jobs),
or a list of job IDs
@rtype: list
@return: the list of job objects
"""
if not job_ids:
job_ids = self._GetJobIDsUnlocked()
return [self._LoadJobUnlocked(job_id) for job_id in job_ids]
@staticmethod
def _IsQueueMarkedDrain():
"""Check if the queue is marked from drain.
This currently uses the queue drain file, which makes it a
per-node flag. In the future this can be moved to the config file.
@rtype: boolean
@return: True of the job queue is marked for draining
"""
return os.path.exists(constants.JOB_QUEUE_DRAIN_FILE)
@staticmethod
def SetDrainFlag(drain_flag):
"""Sets the drain flag for the queue.
This is similar to the function L{backend.JobQueueSetDrainFlag},
and in the future we might merge them.
@type drain_flag: boolean
@param drain_flag: wheter to set or unset the drain flag
"""
if drain_flag:
utils.WriteFile(constants.JOB_QUEUE_DRAIN_FILE, data="", close=True)
else:
utils.RemoveFile(constants.JOB_QUEUE_DRAIN_FILE)
return True
@utils.LockedMethod
@_RequireOpenQueue
def SubmitJob(self, ops):
"""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.
@type ops: list
@param ops: The list of OpCodes that will become the new job.
@rtype: job ID
@return: the job ID of the newly created job
@raise errors.JobQueueDrainError: if the job is marked for draining
"""
if self._IsQueueMarkedDrain():
raise errors.JobQueueDrainError()
# Check job queue size
size = len(self._ListJobFiles())
if size >= constants.JOB_QUEUE_SIZE_SOFT_LIMIT:
# TODO: Autoarchive jobs. Make sure it's not done on every job
# submission, though.
#size = ...
pass
if size >= constants.JOB_QUEUE_SIZE_HARD_LIMIT:
raise errors.JobQueueFull()
# Get job identifier
job_id = self._NewSerialUnlocked()
job = _QueuedJob(self, job_id, ops)
# Write to disk
self.UpdateJobUnlocked(job)
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
@_RequireOpenQueue
def UpdateJobUnlocked(self, job):
"""Update a job's on disk storage.
After a job has been modified, this function needs to be called in
order to write the changes to disk and replicate them to the other
nodes.
@type job: L{_QueuedJob}
@param job: the changed 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
@rtype: tuple (job info, log entries)
@return: a tuple of the job information as required via
the fields parameter, and the log entries as a list
if the job has not changed and the timeout has expired,
we instead return a special value,
L{constants.JOB_NOTCHANGED}, which should be interpreted
as such by the clients
"""
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,
constants.JOB_STATUS_WAITLOCK):
# 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.
This will only succeed if the job has not started yet.
@type job_id: string
@param job_id: job ID of job to be cancelled.
"""
logging.info("Cancelling job %s", job_id)
job = self._LoadJobUnlocked(job_id)
if not job:
logging.debug("Job %s not found", job_id)
return (False, "Job %s not found" % job_id)
job_status = job.CalcStatus()
if job_status not in (constants.JOB_STATUS_QUEUED,
constants.JOB_STATUS_WAITLOCK):
logging.debug("Job %s is no longer in the queue", job.id)
return (False, "Job %s is no longer in the queue" % job.id)
if job_status == constants.JOB_STATUS_QUEUED:
self.CancelJobUnlocked(job)
return (True, "Job %s canceled" % job.id)
elif job_status == constants.JOB_STATUS_WAITLOCK:
# The worker will notice the new status and cancel the job
try:
for op in job.ops:
op.status = constants.OP_STATUS_CANCELING
finally:
self.UpdateJobUnlocked(job)
return (True, "Job %s will be canceled" % job.id)
@_RequireOpenQueue
def CancelJobUnlocked(self, job):
"""Marks a job as canceled.
"""
try:
for op in job.ops:
op.status = constants.OP_STATUS_CANCELED
op.result = "Job canceled by request"
finally:
self.UpdateJobUnlocked(job)
@_RequireOpenQueue
def _ArchiveJobsUnlocked(self, jobs):
"""Archives jobs.
@type jobs: list of L{_QueuedJob}
@param jobs: Job objects
@rtype: int
@return: Number of archived jobs
"""
archive_jobs = []
rename_files = []
for job in jobs:
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)
continue
archive_jobs.append(job)
old = self._GetJobPath(job.id)
new = self._GetArchivedJobPath(job.id)
rename_files.append((old, new))
# TODO: What if 1..n files fail to rename?
self._RenameFilesUnlocked(rename_files)
logging.debug("Successfully archived job(s) %s",
", ".join(job.id for job in archive_jobs))
return len(archive_jobs)
@utils.LockedMethod
@_RequireOpenQueue
def ArchiveJob(self, job_id):
"""Archives a job.
This is just a wrapper over L{_ArchiveJobsUnlocked}.
@type job_id: string
@param job_id: Job ID of job to be archived.
@rtype: bool
@return: Whether job was archived
"""
logging.info("Archiving job %s", job_id)
job = self._LoadJobUnlocked(job_id)
if not job:
logging.debug("Job %s not found", job_id)
return False
return self._ArchiveJobsUnlocked([job]) == 1
@utils.LockedMethod
@_RequireOpenQueue
def AutoArchiveJobs(self, age, timeout):
"""Archives all jobs based on age.
The method will archive all jobs which are older than the age
parameter. For jobs that don't have an end timestamp, the start
timestamp will be considered. The special '-1' age will cause
archival of all jobs (that are not running or queued).
@type age: int
@param age: the minimum age in seconds
"""
logging.info("Archiving jobs with age more than %s seconds", age)
now = time.time()
end_time = now + timeout
archived_count = 0
last_touched = 0
all_job_ids = self._GetJobIDsUnlocked(archived=False)
pending = []
for idx, job_id in enumerate(all_job_ids):
last_touched = idx
# Not optimal because jobs could be pending
# TODO: Measure average duration for job archival and take number of
# pending jobs into account.
if time.time() > end_time:
break
# Returns None if the job failed to load
job = self._LoadJobUnlocked(job_id)
if job:
if job.end_timestamp is None:
if job.start_timestamp is None:
job_age = job.received_timestamp
else:
job_age = job.start_timestamp
else:
job_age = job.end_timestamp
if age == -1 or now - job_age[0] > age:
pending.append(job)
# Archive 10 jobs at a time
if len(pending) >= 10:
archived_count += self._ArchiveJobsUnlocked(pending)
pending = []
if pending:
archived_count += self._ArchiveJobsUnlocked(pending)
return (archived_count, len(all_job_ids) - last_touched - 1)
def _GetJobInfoUnlocked(self, job, fields):
"""Returns information about a job.
@type job: L{_QueuedJob}
@param job: the job which we query
@type fields: list
@param fields: names of fields to return
@rtype: list
@return: list with one element for each field
@raise errors.OpExecError: when an invalid field
has been passed
"""
row = []
for fname in fields:
if fname == "id":
row.append(job.id)
elif fname == "status":
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])
elif fname == "oplog":
row.append([op.log for op in job.ops])
elif fname == "opstart":
row.append([op.start_timestamp for op in job.ops])
elif fname == "opend":
row.append([op.end_timestamp for op in job.ops])
elif fname == "received_ts":
row.append(job.received_timestamp)
elif fname == "start_ts":
row.append(job.start_timestamp)
elif fname == "end_ts":
row.append(job.end_timestamp)
elif fname == "summary":
row.append([op.input.Summary() 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.
This is a wrapper of L{_GetJobsUnlocked}, which actually does the
processing for each job.
@type job_ids: list
@param job_ids: sequence of job identifiers or None for all
@type fields: list
@param fields: names of fields to return
@rtype: list
@return: list one element per job, each element being list with
the requested fields
"""
jobs = []
for job in self._GetJobsUnlocked(job_ids):
if job is None:
jobs.append(None)
else:
jobs.append(self._GetJobInfoUnlocked(job, fields))
return jobs
@utils.LockedMethod
@_RequireOpenQueue
def Shutdown(self):
"""Stops the job queue.
This shutdowns all the worker threads an closes the queue.
"""
self._wpool.TerminateWorkers()
self._queue_lock.Close()
self._queue_lock = None