4 # Copyright (C) 2006, 2007 Google Inc.
6 # This program is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 2 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful, but
12 # WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 # General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
22 """Module implementing the logic behind the cluster operations
24 This module implements the logic for doing operations in the cluster. There
25 are two kinds of classes defined:
26 - logical units, which know how to deal with their specific opcode only
27 - the processor, which dispatches the opcodes to their logical units
35 from ganeti import opcodes
36 from ganeti import constants
37 from ganeti import errors
38 from ganeti import rpc
39 from ganeti import cmdlib
40 from ganeti import locking
41 from ganeti import utils
44 class LockAcquireTimeout(Exception):
45 """Exception to report timeouts on acquiring locks.
50 def _CalculateLockAttemptTimeouts():
51 """Calculate timeouts for lock attempts.
56 # Wait for a total of at least 150s before doing a blocking acquire
57 while sum(result) < 150.0:
58 timeout = (result[-1] * 1.05) ** 1.25
60 # Cap timeout at 10 seconds. This gives other jobs a chance to run
61 # even if we're still trying to get our locks, before finally moving
62 # to a blocking acquire.
67 # Lower boundary for safety
70 result.append(timeout)
75 class LockAttemptTimeoutStrategy(object):
76 """Class with lock acquire timeout strategy.
85 _TIMEOUT_PER_ATTEMPT = _CalculateLockAttemptTimeouts()
87 def __init__(self, _time_fn=time.time, _random_fn=random.random):
88 """Initializes this class.
90 @param _time_fn: Time function for unittests
91 @param _random_fn: Random number generator for unittests
96 self._timeouts = iter(self._TIMEOUT_PER_ATTEMPT)
97 self._time_fn = _time_fn
98 self._random_fn = _random_fn
100 def NextAttempt(self):
101 """Returns the timeout for the next attempt.
105 timeout = self._timeouts.next()
106 except StopIteration:
107 # No more timeouts, do blocking acquire
110 if timeout is not None:
111 # Add a small variation (-/+ 5%) to timeout. This helps in situations
112 # where two or more jobs are fighting for the same lock(s).
113 variation_range = timeout * 0.1
114 timeout += ((self._random_fn() * variation_range) -
115 (variation_range * 0.5))
120 class OpExecCbBase: # pylint: disable-msg=W0232
121 """Base class for OpCode execution callbacks.
124 def NotifyStart(self):
125 """Called when we are about to execute the LU.
127 This function is called when we're about to start the lu's Exec() method,
128 that is, after we have acquired all locks.
132 def Feedback(self, *args):
133 """Sends feedback from the LU code to the end-user.
137 def CheckCancel(self):
138 """Check whether job has been cancelled.
143 class Processor(object):
144 """Object which runs OpCodes"""
147 opcodes.OpPostInitCluster: cmdlib.LUPostInitCluster,
148 opcodes.OpDestroyCluster: cmdlib.LUDestroyCluster,
149 opcodes.OpQueryClusterInfo: cmdlib.LUQueryClusterInfo,
150 opcodes.OpVerifyCluster: cmdlib.LUVerifyCluster,
151 opcodes.OpQueryConfigValues: cmdlib.LUQueryConfigValues,
152 opcodes.OpRenameCluster: cmdlib.LURenameCluster,
153 opcodes.OpVerifyDisks: cmdlib.LUVerifyDisks,
154 opcodes.OpSetClusterParams: cmdlib.LUSetClusterParams,
155 opcodes.OpRedistributeConfig: cmdlib.LURedistributeConfig,
156 opcodes.OpRepairDiskSizes: cmdlib.LURepairDiskSizes,
157 opcodes.OpQuery: cmdlib.LUQuery,
158 opcodes.OpQueryFields: cmdlib.LUQueryFields,
160 opcodes.OpAddNode: cmdlib.LUAddNode,
161 opcodes.OpQueryNodes: cmdlib.LUQueryNodes,
162 opcodes.OpQueryNodeVolumes: cmdlib.LUQueryNodeVolumes,
163 opcodes.OpQueryNodeStorage: cmdlib.LUQueryNodeStorage,
164 opcodes.OpModifyNodeStorage: cmdlib.LUModifyNodeStorage,
165 opcodes.OpRepairNodeStorage: cmdlib.LURepairNodeStorage,
166 opcodes.OpRemoveNode: cmdlib.LURemoveNode,
167 opcodes.OpSetNodeParams: cmdlib.LUSetNodeParams,
168 opcodes.OpPowercycleNode: cmdlib.LUPowercycleNode,
169 opcodes.OpMigrateNode: cmdlib.LUMigrateNode,
170 opcodes.OpNodeEvacuationStrategy: cmdlib.LUNodeEvacuationStrategy,
172 opcodes.OpCreateInstance: cmdlib.LUCreateInstance,
173 opcodes.OpReinstallInstance: cmdlib.LUReinstallInstance,
174 opcodes.OpRemoveInstance: cmdlib.LURemoveInstance,
175 opcodes.OpRenameInstance: cmdlib.LURenameInstance,
176 opcodes.OpActivateInstanceDisks: cmdlib.LUActivateInstanceDisks,
177 opcodes.OpShutdownInstance: cmdlib.LUShutdownInstance,
178 opcodes.OpStartupInstance: cmdlib.LUStartupInstance,
179 opcodes.OpRebootInstance: cmdlib.LURebootInstance,
180 opcodes.OpDeactivateInstanceDisks: cmdlib.LUDeactivateInstanceDisks,
181 opcodes.OpReplaceDisks: cmdlib.LUReplaceDisks,
182 opcodes.OpRecreateInstanceDisks: cmdlib.LURecreateInstanceDisks,
183 opcodes.OpFailoverInstance: cmdlib.LUFailoverInstance,
184 opcodes.OpMigrateInstance: cmdlib.LUMigrateInstance,
185 opcodes.OpMoveInstance: cmdlib.LUMoveInstance,
186 opcodes.OpConnectConsole: cmdlib.LUConnectConsole,
187 opcodes.OpQueryInstances: cmdlib.LUQueryInstances,
188 opcodes.OpQueryInstanceData: cmdlib.LUQueryInstanceData,
189 opcodes.OpSetInstanceParams: cmdlib.LUSetInstanceParams,
190 opcodes.OpGrowDisk: cmdlib.LUGrowDisk,
192 opcodes.OpAddGroup: cmdlib.LUAddGroup,
193 opcodes.OpQueryGroups: cmdlib.LUQueryGroups,
194 opcodes.OpRemoveGroup: cmdlib.LURemoveGroup,
195 opcodes.OpRenameGroup: cmdlib.LURenameGroup,
197 opcodes.OpDiagnoseOS: cmdlib.LUDiagnoseOS,
199 opcodes.OpQueryExports: cmdlib.LUQueryExports,
200 opcodes.OpPrepareExport: cmdlib.LUPrepareExport,
201 opcodes.OpExportInstance: cmdlib.LUExportInstance,
202 opcodes.OpRemoveExport: cmdlib.LURemoveExport,
204 opcodes.OpGetTags: cmdlib.LUGetTags,
205 opcodes.OpSearchTags: cmdlib.LUSearchTags,
206 opcodes.OpAddTags: cmdlib.LUAddTags,
207 opcodes.OpDelTags: cmdlib.LUDelTags,
209 opcodes.OpTestDelay: cmdlib.LUTestDelay,
210 opcodes.OpTestAllocator: cmdlib.LUTestAllocator,
211 opcodes.OpTestJobqueue: cmdlib.LUTestJobqueue,
213 opcodes.OpOutOfBand: cmdlib.LUOutOfBand,
216 def __init__(self, context, ec_id):
217 """Constructor for Processor
219 @type context: GanetiContext
220 @param context: global Ganeti context
222 @param ec_id: execution context identifier
225 self.context = context
228 self.rpc = rpc.RpcRunner(context.cfg)
229 self.hmclass = HooksMaster
231 def _AcquireLocks(self, level, names, shared, timeout, priority):
232 """Acquires locks via the Ganeti lock manager.
235 @param level: Lock level
236 @type names: list or string
237 @param names: Lock names
239 @param shared: Whether the locks should be acquired in shared mode
240 @type timeout: None or float
241 @param timeout: Timeout for acquiring the locks
242 @raise LockAcquireTimeout: In case locks couldn't be acquired in specified
247 self._cbs.CheckCancel()
249 acquired = self.context.glm.acquire(level, names, shared=shared,
250 timeout=timeout, priority=priority)
253 raise LockAcquireTimeout()
257 def _ExecLU(self, lu):
258 """Logical Unit execution sequence.
261 write_count = self.context.cfg.write_count
263 hm = HooksMaster(self.rpc.call_hooks_runner, lu)
264 h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE)
265 lu.HooksCallBack(constants.HOOKS_PHASE_PRE, h_results,
268 if getattr(lu.op, "dry_run", False):
269 # in this mode, no post-hooks are run, and the config is not
270 # written (as it might have been modified by another LU, and we
271 # shouldn't do writeout on behalf of other threads
272 self.LogInfo("dry-run mode requested, not actually executing"
274 return lu.dry_run_result
277 result = lu.Exec(self.Log)
278 h_results = hm.RunPhase(constants.HOOKS_PHASE_POST)
279 result = lu.HooksCallBack(constants.HOOKS_PHASE_POST, h_results,
282 # FIXME: This needs locks if not lu_class.REQ_BGL
283 if write_count != self.context.cfg.write_count:
288 def _LockAndExecLU(self, lu, level, calc_timeout, priority):
289 """Execute a Logical Unit, with the needed locks.
291 This is a recursive function that starts locking the given level, and
292 proceeds up, till there are no more locks to acquire. Then it executes the
293 given LU and its opcodes.
296 adding_locks = level in lu.add_locks
297 acquiring_locks = level in lu.needed_locks
298 if level not in locking.LEVELS:
300 self._cbs.NotifyStart()
302 result = self._ExecLU(lu)
304 elif adding_locks and acquiring_locks:
305 # We could both acquire and add locks at the same level, but for now we
306 # don't need this, so we'll avoid the complicated code needed.
307 raise NotImplementedError("Can't declare locks to acquire when adding"
310 elif adding_locks or acquiring_locks:
311 lu.DeclareLocks(level)
312 share = lu.share_locks[level]
315 assert adding_locks ^ acquiring_locks, \
316 "Locks must be either added or acquired"
320 needed_locks = lu.needed_locks[level]
322 acquired = self._AcquireLocks(level, needed_locks, share,
323 calc_timeout(), priority)
326 add_locks = lu.add_locks[level]
327 lu.remove_locks[level] = add_locks
330 self.context.glm.add(level, add_locks, acquired=1, shared=share)
331 except errors.LockError:
332 raise errors.OpPrereqError(
333 "Couldn't add locks (%s), probably because of a race condition"
334 " with another job, who added them first" % add_locks,
340 lu.acquired_locks[level] = acquired
342 result = self._LockAndExecLU(lu, level + 1, calc_timeout, priority)
344 if level in lu.remove_locks:
345 self.context.glm.remove(level, lu.remove_locks[level])
347 if self.context.glm.is_owned(level):
348 self.context.glm.release(level)
351 result = self._LockAndExecLU(lu, level + 1, calc_timeout, priority)
355 def ExecOpCode(self, op, cbs, timeout=None, priority=None):
356 """Execute an opcode.
358 @type op: an OpCode instance
359 @param op: the opcode to be executed
360 @type cbs: L{OpExecCbBase}
361 @param cbs: Runtime callbacks
362 @type timeout: float or None
363 @param timeout: Maximum time to acquire all locks, None for no timeout
364 @type priority: number or None
365 @param priority: Priority for acquiring lock(s)
366 @raise LockAcquireTimeout: In case locks couldn't be acquired in specified
370 if not isinstance(op, opcodes.OpCode):
371 raise errors.ProgrammerError("Non-opcode instance passed"
374 lu_class = self.DISPATCH_TABLE.get(op.__class__, None)
376 raise errors.OpCodeUnknown("Unknown opcode")
379 calc_timeout = lambda: None
381 calc_timeout = utils.RunningTimeout(timeout, False).Remaining
385 # Acquire the Big Ganeti Lock exclusively if this LU requires it,
386 # and in a shared fashion otherwise (to prevent concurrent run with
388 self._AcquireLocks(locking.LEVEL_CLUSTER, locking.BGL,
389 not lu_class.REQ_BGL, calc_timeout(),
392 lu = lu_class(self, op, self.context, self.rpc)
394 assert lu.needed_locks is not None, "needed_locks not set by LU"
397 return self._LockAndExecLU(lu, locking.LEVEL_INSTANCE, calc_timeout,
401 self.context.cfg.DropECReservations(self._ec_id)
403 self.context.glm.release(locking.LEVEL_CLUSTER)
407 def Log(self, *args):
408 """Forward call to feedback callback function.
412 self._cbs.Feedback(*args)
414 def LogStep(self, current, total, message):
415 """Log a change in LU execution progress.
418 logging.debug("Step %d/%d %s", current, total, message)
419 self.Log("STEP %d/%d %s" % (current, total, message))
421 def LogWarning(self, message, *args, **kwargs):
422 """Log a warning to the logs and the user.
424 The optional keyword argument is 'hint' and can be used to show a
425 hint to the user (presumably related to the warning). If the
426 message is empty, it will not be printed at all, allowing one to
430 assert not kwargs or (len(kwargs) == 1 and "hint" in kwargs), \
431 "Invalid keyword arguments for LogWarning (%s)" % str(kwargs)
433 message = message % tuple(args)
435 logging.warning(message)
436 self.Log(" - WARNING: %s" % message)
438 self.Log(" Hint: %s" % kwargs["hint"])
440 def LogInfo(self, message, *args):
441 """Log an informational message to the logs and the user.
445 message = message % tuple(args)
446 logging.info(message)
447 self.Log(" - INFO: %s" % message)
451 errors.ProgrammerError("Tried to use execution context id when not set")
455 class HooksMaster(object):
458 This class distributes the run commands to the nodes based on the
461 In order to remove the direct dependency on the rpc module, the
462 constructor needs a function which actually does the remote
463 call. This will usually be rpc.call_hooks_runner, but any function
464 which behaves the same works.
467 def __init__(self, callfn, lu):
471 self.env, node_list_pre, node_list_post = self._BuildEnv()
472 self.node_list = {constants.HOOKS_PHASE_PRE: node_list_pre,
473 constants.HOOKS_PHASE_POST: node_list_post}
476 """Compute the environment and the target nodes.
478 Based on the opcode and the current node list, this builds the
479 environment for the hooks and the target node list for the run.
483 "PATH": "/sbin:/bin:/usr/sbin:/usr/bin",
484 "GANETI_HOOKS_VERSION": constants.HOOKS_VERSION,
485 "GANETI_OP_CODE": self.op.OP_ID,
486 "GANETI_OBJECT_TYPE": self.lu.HTYPE,
487 "GANETI_DATA_DIR": constants.DATA_DIR,
490 if self.lu.HPATH is not None:
491 lu_env, lu_nodes_pre, lu_nodes_post = self.lu.BuildHooksEnv()
494 env["GANETI_" + key] = lu_env[key]
496 lu_nodes_pre = lu_nodes_post = []
498 return env, frozenset(lu_nodes_pre), frozenset(lu_nodes_post)
500 def _RunWrapper(self, node_list, hpath, phase):
501 """Simple wrapper over self.callfn.
503 This method fixes the environment before doing the rpc call.
506 env = self.env.copy()
507 env["GANETI_HOOKS_PHASE"] = phase
508 env["GANETI_HOOKS_PATH"] = hpath
509 if self.lu.cfg is not None:
510 env["GANETI_CLUSTER"] = self.lu.cfg.GetClusterName()
511 env["GANETI_MASTER"] = self.lu.cfg.GetMasterNode()
513 env = dict([(str(key), str(val)) for key, val in env.iteritems()])
515 return self.callfn(node_list, hpath, phase, env)
517 def RunPhase(self, phase, nodes=None):
518 """Run all the scripts for a phase.
520 This is the main function of the HookMaster.
522 @param phase: one of L{constants.HOOKS_PHASE_POST} or
523 L{constants.HOOKS_PHASE_PRE}; it denotes the hooks phase
524 @param nodes: overrides the predefined list of nodes for the given phase
525 @return: the processed results of the hooks multi-node rpc call
526 @raise errors.HooksFailure: on communication failure to the nodes
527 @raise errors.HooksAbort: on failure of one of the hooks
530 if not self.node_list[phase] and not nodes:
531 # empty node list, we should not attempt to run this as either
532 # we're in the cluster init phase and the rpc client part can't
533 # even attempt to run, or this LU doesn't do hooks at all
535 hpath = self.lu.HPATH
536 if nodes is not None:
537 results = self._RunWrapper(nodes, hpath, phase)
539 results = self._RunWrapper(self.node_list[phase], hpath, phase)
542 msg = "Communication Failure"
543 if phase == constants.HOOKS_PHASE_PRE:
544 raise errors.HooksFailure(msg)
546 self.lu.LogWarning(msg)
548 for node_name in results:
549 res = results[node_name]
554 self.lu.LogWarning("Communication failure to node %s: %s",
557 for script, hkr, output in res.payload:
558 if hkr == constants.HKR_FAIL:
559 if phase == constants.HOOKS_PHASE_PRE:
560 errs.append((node_name, script, output))
563 output = "(no output)"
564 self.lu.LogWarning("On %s script %s failed, output: %s" %
565 (node_name, script, output))
566 if errs and phase == constants.HOOKS_PHASE_PRE:
567 raise errors.HooksAbort(errs)
570 def RunConfigUpdate(self):
571 """Run the special configuration update hook
573 This is a special hook that runs only on the master after each
574 top-level LI if the configuration has been updated.
577 phase = constants.HOOKS_PHASE_POST
578 hpath = constants.HOOKS_NAME_CFGUPDATE
579 nodes = [self.lu.cfg.GetMasterNode()]
580 self._RunWrapper(nodes, hpath, phase)