jqueue.py 16.8 KB
Newer Older
Iustin Pop's avatar
Iustin Pop committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
#
#

# Copyright (C) 2006, 2007 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."""

24
import os
Michael Hanselmann's avatar
Michael Hanselmann committed
25 26
import logging
import threading
27 28
import errno
import re
29
import time
Iustin Pop's avatar
Iustin Pop committed
30

Michael Hanselmann's avatar
Michael Hanselmann committed
31
from ganeti import constants
32
from ganeti import serializer
Michael Hanselmann's avatar
Michael Hanselmann committed
33
from ganeti import workerpool
34
from ganeti import opcodes
Iustin Pop's avatar
Iustin Pop committed
35
from ganeti import errors
Michael Hanselmann's avatar
Michael Hanselmann committed
36
from ganeti import mcpu
37
from ganeti import utils
38
from ganeti import rpc
Michael Hanselmann's avatar
Michael Hanselmann committed
39 40 41 42


JOBQUEUE_THREADS = 5

Iustin Pop's avatar
Iustin Pop committed
43

Michael Hanselmann's avatar
Michael Hanselmann committed
44 45 46
class _QueuedOpCode(object):
  """Encasulates an opcode object.

47
  Access is synchronized by the '_lock' attribute.
Michael Hanselmann's avatar
Michael Hanselmann committed
48

49 50 51
  The 'log' attribute holds the execution log and consists of tuples
  of the form (timestamp, level, message).

Michael Hanselmann's avatar
Michael Hanselmann committed
52 53
  """
  def __init__(self, op):
54
    self.__Setup(op, constants.OP_STATUS_QUEUED, None, [])
55

56
  def __Setup(self, input_, status, result, log):
57
    self._lock = threading.Lock()
58
    self.input = input_
59 60
    self.status = status
    self.result = result
61
    self.log = log
62 63 64 65 66

  @classmethod
  def Restore(cls, state):
    obj = object.__new__(cls)
    obj.__Setup(opcodes.OpCode.LoadOpCode(state["input"]),
67
                state["status"], state["result"], state["log"])
68 69 70 71 72 73 74 75
    return obj

  @utils.LockedMethod
  def Serialize(self):
    return {
      "input": self.input.__getstate__(),
      "status": self.status,
      "result": self.result,
76
      "log": self.log,
77
      }
78

79 80 81 82 83 84 85
  @utils.LockedMethod
  def GetInput(self):
    """Returns the original opcode.

    """
    return self.input

86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106
  @utils.LockedMethod
  def SetStatus(self, status, result):
    """Update the opcode status and result.

    """
    self.status = status
    self.result = result

  @utils.LockedMethod
  def GetStatus(self):
    """Get the opcode status.

    """
    return self.status

  @utils.LockedMethod
  def GetResult(self):
    """Get the opcode result.

    """
    return self.result
Michael Hanselmann's avatar
Michael Hanselmann committed
107

108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128
  @utils.LockedMethod
  def Log(self, *args):
    """Append a log entry.

    """
    assert len(args) < 2

    if len(args) == 1:
      log_type = constants.ELOG_MESSAGE
      log_msg = args[0]
    else:
      log_type, log_msg = args
    self.log.append((time.time(), log_type, log_msg))

  @utils.LockedMethod
  def RetrieveLog(self, start_at=0):
    """Retrieve (a part of) the execution log.

    """
    return self.log[start_at:]

Michael Hanselmann's avatar
Michael Hanselmann committed
129 130 131 132 133 134 135

class _QueuedJob(object):
  """In-memory job representation.

  This is what we use to track the user-submitted jobs.

  """
136
  def __init__(self, storage, job_id, ops):
Michael Hanselmann's avatar
Michael Hanselmann committed
137 138 139 140
    if not ops:
      # TODO
      raise Exception("No opcodes")

141
    self.__Setup(storage, job_id, [_QueuedOpCode(op) for op in ops], -1)
Michael Hanselmann's avatar
Michael Hanselmann committed
142

143 144
  def __Setup(self, storage, job_id, ops, run_op_index):
    self._lock = threading.Lock()
145 146 147
    self.storage = storage
    self.id = job_id
    self._ops = ops
148
    self.run_op_index = run_op_index
149 150 151 152

  @classmethod
  def Restore(cls, storage, state):
    obj = object.__new__(cls)
153 154
    op_list = [_QueuedOpCode.Restore(op_state) for op_state in state["ops"]]
    obj.__Setup(storage, state["id"], op_list, state["run_op_index"])
155 156 157 158 159 160
    return obj

  def Serialize(self):
    return {
      "id": self.id,
      "ops": [op.Serialize() for op in self._ops],
161
      "run_op_index": self.run_op_index,
162 163 164 165 166 167 168 169
      }

  def SetUnclean(self, msg):
    try:
      for op in self._ops:
        op.SetStatus(constants.OP_STATUS_ERROR, msg)
    finally:
      self.storage.UpdateJob(self)
Michael Hanselmann's avatar
Michael Hanselmann committed
170

171
  def GetStatus(self):
Michael Hanselmann's avatar
Michael Hanselmann committed
172 173 174 175
    status = constants.JOB_STATUS_QUEUED

    all_success = True
    for op in self._ops:
176 177
      op_status = op.GetStatus()
      if op_status == constants.OP_STATUS_SUCCESS:
Michael Hanselmann's avatar
Michael Hanselmann committed
178 179 180 181
        continue

      all_success = False

182
      if op_status == constants.OP_STATUS_QUEUED:
Michael Hanselmann's avatar
Michael Hanselmann committed
183
        pass
184
      elif op_status == constants.OP_STATUS_RUNNING:
Michael Hanselmann's avatar
Michael Hanselmann committed
185
        status = constants.JOB_STATUS_RUNNING
186 187 188 189
      elif op_status == constants.OP_STATUS_ERROR:
        status = constants.JOB_STATUS_ERROR
        # The whole job fails if one opcode failed
        break
Michael Hanselmann's avatar
Michael Hanselmann committed
190 191 192 193 194 195

    if all_success:
      status = constants.JOB_STATUS_SUCCESS

    return status

196 197 198 199
  @utils.LockedMethod
  def GetRunOpIndex(self):
    return self.run_op_index

Michael Hanselmann's avatar
Michael Hanselmann committed
200 201 202 203 204 205 206 207 208 209 210
  def Run(self, proc):
    """Job executor.

    This functions processes a this job in the context of given processor
    instance.

    Args:
    - proc: Ganeti Processor to run the job with

    """
    try:
211 212
      count = len(self._ops)
      for idx, op in enumerate(self._ops):
Michael Hanselmann's avatar
Michael Hanselmann committed
213
        try:
214
          logging.debug("Op %s/%s: Starting %s", idx + 1, count, op)
215 216 217 218 219 220 221

          self._lock.acquire()
          try:
            self.run_op_index = idx
          finally:
            self._lock.release()

222
          op.SetStatus(constants.OP_STATUS_RUNNING, None)
223
          self.storage.UpdateJob(self)
Michael Hanselmann's avatar
Michael Hanselmann committed
224

225
          result = proc.ExecOpCode(op.input, op.Log)
Michael Hanselmann's avatar
Michael Hanselmann committed
226

227
          op.SetStatus(constants.OP_STATUS_SUCCESS, result)
228
          self.storage.UpdateJob(self)
229 230
          logging.debug("Op %s/%s: Successfully finished %s",
                        idx + 1, count, op)
Michael Hanselmann's avatar
Michael Hanselmann committed
231
        except Exception, err:
232 233 234 235 236
          try:
            op.SetStatus(constants.OP_STATUS_ERROR, str(err))
            logging.debug("Op %s/%s: Error in %s", idx + 1, count, op)
          finally:
            self.storage.UpdateJob(self)
Michael Hanselmann's avatar
Michael Hanselmann committed
237 238 239 240 241 242 243 244 245 246 247 248 249 250 251
          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
252
    proc = mcpu.Processor(self.pool.context)
Michael Hanselmann's avatar
Michael Hanselmann committed
253 254 255 256 257 258 259 260 261 262 263 264 265 266
    try:
      job.Run(proc)
    finally:
      logging.debug("Worker %s finished job %s, status = %s",
                    self.worker_id, job.id, job.GetStatus())


class _JobQueueWorkerPool(workerpool.WorkerPool):
  def __init__(self, context):
    super(_JobQueueWorkerPool, self).__init__(JOBQUEUE_THREADS,
                                              _JobQueueWorker)
    self.context = context


267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296
class JobStorageBase(object):
  def __init__(self, id_prefix):
    self.id_prefix = id_prefix

    if id_prefix:
      prefix_pattern = re.escape("%s-" % id_prefix)
    else:
      prefix_pattern = ""

    # Apart from the prefix, all job IDs are numeric
    self._re_job_id = re.compile(r"^%s\d+$" % prefix_pattern)

  def OwnsJobId(self, job_id):
    return self._re_job_id.match(job_id)

  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)

    if self.id_prefix:
      prefix = "%s-" % self.id_prefix
    else:
      prefix = ""

    return "%s%010d" % (prefix, job_id)


class DiskJobStorage(JobStorageBase):
297
  _RE_JOB_FILE = re.compile(r"^job-(%s)$" % constants.JOB_ID_TEMPLATE)
298

299 300 301
  def __init__(self, id_prefix):
    JobStorageBase.__init__(self, id_prefix)

302
    self._lock = threading.Lock()
Iustin Pop's avatar
Iustin Pop committed
303
    self._memcache = {}
304
    self._my_hostname = utils.HostInfo().name
305

306 307 308 309 310 311 312
    # Make sure our directories exists
    for path in (constants.QUEUE_DIR, constants.JOB_QUEUE_ARCHIVE_DIR):
      try:
        os.mkdir(path, 0700)
      except OSError, err:
        if err.errno not in (errno.EEXIST, ):
          raise
313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345

    # Get queue lock
    self.lock_fd = open(constants.JOB_QUEUE_LOCK_FILE, "w")
    try:
      utils.LockFile(self.lock_fd)
    except:
      self.lock_fd.close()
      raise

    # Read version
    try:
      version_fd = open(constants.JOB_QUEUE_VERSION_FILE, "r")
    except IOError, err:
      if err.errno not in (errno.ENOENT, ):
        raise

      # Setup a new queue
      self._InitQueueUnlocked()

      # Try to open again
      version_fd = open(constants.JOB_QUEUE_VERSION_FILE, "r")

    try:
      # Try to read version
      version = int(version_fd.read(128))

      # Verify version
      if version != constants.JOB_QUEUE_VERSION:
        raise errors.JobQueueError("Found version %s, expected %s",
                                   version, constants.JOB_QUEUE_VERSION)
    finally:
      version_fd.close()

346 347 348 349 350 351 352 353 354 355 356 357 358 359
    self._last_serial = self._ReadSerial()
    if self._last_serial is None:
      raise errors.ConfigurationError("Can't read/parse the job queue serial"
                                      " file")

  @staticmethod
  def _ReadSerial():
    """Try to read the job serial file.

    @rtype: None or int
    @return: If the serial can be read, then it is returned. Otherwise None
             is returned.

    """
360
    try:
361 362 363 364 365 366 367 368 369 370
      serial_fd = open(constants.JOB_QUEUE_SERIAL_FILE, "r")
      try:
        # Read last serial
        serial = int(serial_fd.read(1024).strip())
      finally:
        serial_fd.close()
    except (ValueError, EnvironmentError):
      serial = None

    return serial
371 372 373 374 375 376 377 378 379 380 381 382

  def Close(self):
    assert self.lock_fd, "Queue should be open"

    self.lock_fd.close()
    self.lock_fd = None

  def _InitQueueUnlocked(self):
    assert self.lock_fd, "Queue should be open"

    utils.WriteFile(constants.JOB_QUEUE_VERSION_FILE,
                    data="%s\n" % constants.JOB_QUEUE_VERSION)
383 384 385
    if self._ReadSerial() is None:
      utils.WriteFile(constants.JOB_QUEUE_SERIAL_FILE,
                      data="%s\n" % 0)
386

387
  def _NewSerialUnlocked(self, nodes):
388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406
    """Generates a new job identifier.

    Job identifiers are unique during the lifetime of a cluster.

    Returns: A string representing the job identifier.

    """
    assert self.lock_fd, "Queue should be open"

    # New number
    serial = self._last_serial + 1

    # Write to file
    utils.WriteFile(constants.JOB_QUEUE_SERIAL_FILE,
                    data="%s\n" % serial)

    # Keep it only if we were able to write the file
    self._last_serial = serial

407 408 409 410 411 412 413 414 415 416 417
    # Distribute the serial to the other nodes
    try:
      nodes.remove(self._my_hostname)
    except ValueError:
      pass

    result = rpc.call_upload_file(nodes, constants.JOB_QUEUE_SERIAL_FILE)
    for node in nodes:
      if not result[node]:
        logging.error("copy of job queue file to node %s failed", node)

418
    return self.FormatJobID(serial)
419 420 421 422

  def _GetJobPath(self, job_id):
    return os.path.join(constants.QUEUE_DIR, "job-%s" % job_id)

423 424 425
  def _GetArchivedJobPath(self, job_id):
    return os.path.join(constants.JOB_QUEUE_ARCHIVE_DIR, "job-%s" % job_id)

426 427 428 429 430 431
  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.

Iustin Pop's avatar
Iustin Pop committed
432 433 434 435
    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).

436 437
    """
    jfiles = self._ListJobFiles()
438
    jlist = [m.group(1) for m in
439 440 441
             [self._RE_JOB_FILE.match(name) for name in jfiles]]
    jlist.sort()
    return jlist
442

443 444 445 446 447 448
  def _ListJobFiles(self):
    assert self.lock_fd, "Queue should be open"

    return [name for name in utils.ListVisibleFiles(constants.QUEUE_DIR)
            if self._RE_JOB_FILE.match(name)]

449
  def _LoadJobUnlocked(self, job_id):
450 451
    assert self.lock_fd, "Queue should be open"

Iustin Pop's avatar
Iustin Pop committed
452
    if job_id in self._memcache:
453
      logging.debug("Found job %s in memcache", job_id)
Iustin Pop's avatar
Iustin Pop committed
454 455
      return self._memcache[job_id]

456
    filepath = self._GetJobPath(job_id)
457 458 459 460 461 462 463 464 465 466 467 468
    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()

Iustin Pop's avatar
Iustin Pop committed
469 470
    job = _QueuedJob.Restore(self, data)
    self._memcache[job_id] = job
471
    logging.debug("Added job %s to the cache", job_id)
Iustin Pop's avatar
Iustin Pop committed
472
    return job
473 474

  def _GetJobsUnlocked(self, job_ids):
475 476
    if not job_ids:
      job_ids = self._GetJobIDsUnlocked()
477

478
    return [self._LoadJobUnlocked(job_id) for job_id in job_ids]
479 480 481 482 483 484

  @utils.LockedMethod
  def GetJobs(self, job_ids):
    return self._GetJobsUnlocked(job_ids)

  @utils.LockedMethod
485 486 487 488
  def AddJob(self, ops, nodes):
    """Create and store on disk a new job.

    @type ops: list
489
    @param ops: The list of OpCodes that will become the new job.
490 491 492 493 494
    @type nodes: list
    @param nodes: The list of nodes to which the new job serial will be
                  distributed.

    """
495 496 497
    assert self.lock_fd, "Queue should be open"

    # Get job identifier
498
    job_id = self._NewSerialUnlocked(nodes)
499 500 501 502 503
    job = _QueuedJob(self, job_id, ops)

    # Write to disk
    self._UpdateJobUnlocked(job)

504
    logging.debug("Added new job %s to the cache", job_id)
Iustin Pop's avatar
Iustin Pop committed
505 506
    self._memcache[job_id] = job

507 508 509 510 511 512 513 514 515
    return job

  def _UpdateJobUnlocked(self, job):
    assert self.lock_fd, "Queue should be open"

    filename = self._GetJobPath(job.id)
    logging.debug("Writing job %s to %s", job.id, filename)
    utils.WriteFile(filename,
                    data=serializer.DumpJson(job.Serialize(), indent=False))
516
    self._CleanCacheUnlocked([job.id])
Iustin Pop's avatar
Iustin Pop committed
517

518
  def _CleanCacheUnlocked(self, exclude):
Iustin Pop's avatar
Iustin Pop committed
519 520 521 522 523 524
    """Clean the memory cache.

    The exceptions argument contains job IDs that should not be
    cleaned.

    """
525
    assert isinstance(exclude, list)
Iustin Pop's avatar
Iustin Pop committed
526
    for job in self._memcache.values():
527
      if job.id in exclude:
Iustin Pop's avatar
Iustin Pop committed
528 529 530
        continue
      if job.GetStatus() not in (constants.JOB_STATUS_QUEUED,
                                 constants.JOB_STATUS_RUNNING):
531
        logging.debug("Cleaning job %s from the cache", job.id)
Iustin Pop's avatar
Iustin Pop committed
532 533 534 535
        try:
          del self._memcache[job.id]
        except KeyError:
          pass
536 537 538 539 540 541 542 543 544

  @utils.LockedMethod
  def UpdateJob(self, job):
    return self._UpdateJobUnlocked(job)

  def ArchiveJob(self, job_id):
    raise NotImplementedError()


Michael Hanselmann's avatar
Michael Hanselmann committed
545 546 547
class JobQueue:
  """The job queue.

548
  """
Michael Hanselmann's avatar
Michael Hanselmann committed
549 550
  def __init__(self, context):
    self._lock = threading.Lock()
551
    self._jobs = DiskJobStorage("")
Michael Hanselmann's avatar
Michael Hanselmann committed
552 553
    self._wpool = _JobQueueWorkerPool(context)

554 555 556 557
    for job in self._jobs.GetJobs(None):
      status = job.GetStatus()
      if status in (constants.JOB_STATUS_QUEUED, ):
        self._wpool.AddTask(job)
Michael Hanselmann's avatar
Michael Hanselmann committed
558

559 560 561
      elif status in (constants.JOB_STATUS_RUNNING, ):
        logging.warning("Unfinished job %s found: %s", job.id, job)
        job.SetUnclean("Unclean master daemon shutdown")
Michael Hanselmann's avatar
Michael Hanselmann committed
562

563
  @utils.LockedMethod
564
  def SubmitJob(self, ops, nodes):
Michael Hanselmann's avatar
Michael Hanselmann committed
565 566 567 568 569
    """Add a new job to the queue.

    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.

570 571 572 573 574
    @type ops: list
    @param ops: the sequence of opcodes that will become the new job
    @type nodes: list
    @param nodes: the list of nodes to which the queue should be
                  distributed
Michael Hanselmann's avatar
Michael Hanselmann committed
575 576

    """
577
    job = self._jobs.AddJob(ops, nodes)
Michael Hanselmann's avatar
Michael Hanselmann committed
578 579 580 581

    # Add to worker pool
    self._wpool.AddTask(job)

582
    return job.id
Michael Hanselmann's avatar
Michael Hanselmann committed
583 584 585 586 587 588 589 590 591 592 593 594 595 596

  def ArchiveJob(self, job_id):
    raise NotImplementedError()

  def CancelJob(self, job_id):
    raise NotImplementedError()

  def _GetJobInfo(self, job, fields):
    row = []
    for fname in fields:
      if fname == "id":
        row.append(job.id)
      elif fname == "status":
        row.append(job.GetStatus())
597 598 599
      elif fname == "ops":
        row.append([op.GetInput().__getstate__() for op in job._ops])
      elif fname == "opresult":
600
        row.append([op.GetResult() for op in job._ops])
601 602
      elif fname == "opstatus":
        row.append([op.GetStatus() for op in job._ops])
603 604 605 606 607 608 609 610 611 612 613 614
      elif fname == "ticker":
        ji = job.GetRunOpIndex()
        if ji < 0:
          lmsg = None
        else:
          lmsg = job._ops[ji].RetrieveLog(-1)
          # message might be empty here
          if lmsg:
            lmsg = lmsg[0]
          else:
            lmsg = None
        row.append(lmsg)
Michael Hanselmann's avatar
Michael Hanselmann committed
615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630
      else:
        raise errors.OpExecError("Invalid job query field '%s'" % fname)
    return row

  def QueryJobs(self, job_ids, fields):
    """Returns a list of jobs in queue.

    Args:
    - job_ids: Sequence of job identifiers or None for all
    - fields: Names of fields to return

    """
    self._lock.acquire()
    try:
      jobs = []

631
      for job in self._jobs.GetJobs(job_ids):
Michael Hanselmann's avatar
Michael Hanselmann committed
632 633 634 635 636 637 638 639 640
        if job is None:
          jobs.append(None)
        else:
          jobs.append(self._GetJobInfo(job, fields))

      return jobs
    finally:
      self._lock.release()

641
  @utils.LockedMethod
Michael Hanselmann's avatar
Michael Hanselmann committed
642 643 644 645 646
  def Shutdown(self):
    """Stops the job queue.

    """
    self._wpool.TerminateWorkers()
647
    self._jobs.Close()