X-Git-Url: https://code.grnet.gr/git/ganeti-local/blobdiff_plain/64381ad70b72ac2638c73b0653b912f5cc8ca441..eb58f7bdc72cf84ef8f41bb727e3c81906c00357:/lib/mcpu.py?ds=sidebyside diff --git a/lib/mcpu.py b/lib/mcpu.py index a802051..933d596 100644 --- a/lib/mcpu.py +++ b/lib/mcpu.py @@ -28,33 +28,163 @@ are two kinds of classes defined: """ +import logging +import random +import time from ganeti import opcodes from ganeti import constants from ganeti import errors from ganeti import rpc from ganeti import cmdlib -from ganeti import ssconf -from ganeti import logger from ganeti import locking +class _LockAcquireTimeout(Exception): + """Internal exception to report timeouts on acquiring locks. + + """ + + +def _CalculateLockAttemptTimeouts(): + """Calculate timeouts for lock attempts. + + """ + result = [1.0] + + # Wait for a total of at least 150s before doing a blocking acquire + while sum(result) < 150.0: + timeout = (result[-1] * 1.05) ** 1.25 + + # Cap timeout at 10 seconds. This gives other jobs a chance to run + # even if we're still trying to get our locks, before finally moving + # to a blocking acquire. + if timeout > 10.0: + timeout = 10.0 + + elif timeout < 0.1: + # Lower boundary for safety + timeout = 0.1 + + result.append(timeout) + + return result + + +class _LockAttemptTimeoutStrategy(object): + """Class with lock acquire timeout strategy. + + """ + __slots__ = [ + "_attempt", + "_random_fn", + "_start_time", + "_time_fn", + "_running_timeout", + ] + + _TIMEOUT_PER_ATTEMPT = _CalculateLockAttemptTimeouts() + + def __init__(self, attempt=0, _time_fn=time.time, _random_fn=random.random): + """Initializes this class. + + @type attempt: int + @param attempt: Current attempt number + @param _time_fn: Time function for unittests + @param _random_fn: Random number generator for unittests + + """ + object.__init__(self) + + if attempt < 0: + raise ValueError("Attempt must be zero or positive") + + self._attempt = attempt + self._time_fn = _time_fn + self._random_fn = _random_fn + + try: + timeout = self._TIMEOUT_PER_ATTEMPT[attempt] + except IndexError: + # No more timeouts, do blocking acquire + timeout = None + + self._running_timeout = locking.RunningTimeout(timeout, False, + _time_fn=_time_fn) + + def NextAttempt(self): + """Returns the strategy for the next attempt. + + """ + return _LockAttemptTimeoutStrategy(attempt=self._attempt + 1, + _time_fn=self._time_fn, + _random_fn=self._random_fn) + + def CalcRemainingTimeout(self): + """Returns the remaining timeout. + + """ + timeout = self._running_timeout.Remaining() + + if timeout is not None: + # Add a small variation (-/+ 5%) to timeout. This helps in situations + # where two or more jobs are fighting for the same lock(s). + variation_range = timeout * 0.1 + timeout += ((self._random_fn() * variation_range) - + (variation_range * 0.5)) + + return timeout + + +class OpExecCbBase: # pylint: disable-msg=W0232 + """Base class for OpCode execution callbacks. + + """ + def NotifyStart(self): + """Called when we are about to execute the LU. + + This function is called when we're about to start the lu's Exec() method, + that is, after we have acquired all locks. + + """ + + def Feedback(self, *args): + """Sends feedback from the LU code to the end-user. + + """ + + def ReportLocks(self, msg): + """Report lock operations. + + """ + + class Processor(object): """Object which runs OpCodes""" DISPATCH_TABLE = { # Cluster + opcodes.OpPostInitCluster: cmdlib.LUPostInitCluster, opcodes.OpDestroyCluster: cmdlib.LUDestroyCluster, opcodes.OpQueryClusterInfo: cmdlib.LUQueryClusterInfo, opcodes.OpVerifyCluster: cmdlib.LUVerifyCluster, - opcodes.OpDumpClusterConfig: cmdlib.LUDumpClusterConfig, + opcodes.OpQueryConfigValues: cmdlib.LUQueryConfigValues, opcodes.OpRenameCluster: cmdlib.LURenameCluster, opcodes.OpVerifyDisks: cmdlib.LUVerifyDisks, opcodes.OpSetClusterParams: cmdlib.LUSetClusterParams, + opcodes.OpRedistributeConfig: cmdlib.LURedistributeConfig, + opcodes.OpRepairDiskSizes: cmdlib.LURepairDiskSizes, # node lu opcodes.OpAddNode: cmdlib.LUAddNode, opcodes.OpQueryNodes: cmdlib.LUQueryNodes, opcodes.OpQueryNodeVolumes: cmdlib.LUQueryNodeVolumes, + opcodes.OpQueryNodeStorage: cmdlib.LUQueryNodeStorage, + opcodes.OpModifyNodeStorage: cmdlib.LUModifyNodeStorage, + opcodes.OpRepairNodeStorage: cmdlib.LURepairNodeStorage, opcodes.OpRemoveNode: cmdlib.LURemoveNode, + opcodes.OpSetNodeParams: cmdlib.LUSetNodeParams, + opcodes.OpPowercycleNode: cmdlib.LUPowercycleNode, + opcodes.OpEvacuateNode: cmdlib.LUEvacuateNode, + opcodes.OpMigrateNode: cmdlib.LUMigrateNode, # instance lu opcodes.OpCreateInstance: cmdlib.LUCreateInstance, opcodes.OpReinstallInstance: cmdlib.LUReinstallInstance, @@ -66,7 +196,10 @@ class Processor(object): opcodes.OpRebootInstance: cmdlib.LURebootInstance, opcodes.OpDeactivateInstanceDisks: cmdlib.LUDeactivateInstanceDisks, opcodes.OpReplaceDisks: cmdlib.LUReplaceDisks, + opcodes.OpRecreateInstanceDisks: cmdlib.LURecreateInstanceDisks, opcodes.OpFailoverInstance: cmdlib.LUFailoverInstance, + opcodes.OpMigrateInstance: cmdlib.LUMigrateInstance, + opcodes.OpMoveInstance: cmdlib.LUMoveInstance, opcodes.OpConnectConsole: cmdlib.LUConnectConsole, opcodes.OpQueryInstances: cmdlib.LUQueryInstances, opcodes.OpQueryInstanceData: cmdlib.LUQueryInstanceData, @@ -88,16 +221,95 @@ class Processor(object): opcodes.OpTestAllocator: cmdlib.LUTestAllocator, } - def __init__(self, context): + def __init__(self, context, ec_id): """Constructor for Processor - Args: - - feedback_fn: the feedback function (taking one string) to be run when - interesting events are happening + @type context: GanetiContext + @param context: global Ganeti context + @type ec_id: string + @param ec_id: execution context identifier + """ self.context = context - self._feedback_fn = None - self.exclusive_BGL = False + self._ec_id = ec_id + self._cbs = None + self.rpc = rpc.RpcRunner(context.cfg) + self.hmclass = HooksMaster + + def _ReportLocks(self, level, names, shared, timeout, acquired, result): + """Reports lock operations. + + @type level: int + @param level: Lock level + @type names: list or string + @param names: Lock names + @type shared: bool + @param shared: Whether the locks should be acquired in shared mode + @type timeout: None or float + @param timeout: Timeout for acquiring the locks + @type acquired: bool + @param acquired: Whether the locks have already been acquired + @type result: None or set + @param result: Result from L{locking.GanetiLockManager.acquire} + + """ + parts = [] + + # Build message + if acquired: + if result is None: + parts.append("timeout") + else: + parts.append("acquired") + else: + parts.append("waiting") + if timeout is None: + parts.append("blocking") + else: + parts.append("timeout=%0.6fs" % timeout) + + parts.append(locking.LEVEL_NAMES[level]) + + if names == locking.ALL_SET: + parts.append("ALL") + elif isinstance(names, basestring): + parts.append(names) + else: + parts.append(",".join(sorted(names))) + + if shared: + parts.append("shared") + else: + parts.append("exclusive") + + msg = "/".join(parts) + + logging.debug("LU locks %s", msg) + + if self._cbs: + self._cbs.ReportLocks(msg) + + def _AcquireLocks(self, level, names, shared, timeout): + """Acquires locks via the Ganeti lock manager. + + @type level: int + @param level: Lock level + @type names: list or string + @param names: Lock names + @type shared: bool + @param shared: Whether the locks should be acquired in shared mode + @type timeout: None or float + @param timeout: Timeout for acquiring the locks + + """ + self._ReportLocks(level, names, shared, timeout, False, None) + + acquired = self.context.glm.acquire(level, names, shared=shared, + timeout=timeout) + + self._ReportLocks(level, names, shared, timeout, True, acquired) + + return acquired def _ExecLU(self, lu): """Logical Unit execution sequence. @@ -105,15 +317,24 @@ class Processor(object): """ write_count = self.context.cfg.write_count lu.CheckPrereq() - hm = HooksMaster(rpc.call_hooks_runner, self, lu) + hm = HooksMaster(self.rpc.call_hooks_runner, lu) h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE) lu.HooksCallBack(constants.HOOKS_PHASE_PRE, h_results, - self._feedback_fn, None) + self._Feedback, None) + + if getattr(lu.op, "dry_run", False): + # in this mode, no post-hooks are run, and the config is not + # written (as it might have been modified by another LU, and we + # shouldn't do writeout on behalf of other threads + self.LogInfo("dry-run mode requested, not actually executing" + " the operation") + return lu.dry_run_result + try: - result = lu.Exec(self._feedback_fn) + result = lu.Exec(self._Feedback) h_results = hm.RunPhase(constants.HOOKS_PHASE_POST) result = lu.HooksCallBack(constants.HOOKS_PHASE_POST, h_results, - self._feedback_fn, result) + self._Feedback, result) finally: # FIXME: This needs locks if not lu_class.REQ_BGL if write_count != self.context.cfg.write_count: @@ -121,7 +342,7 @@ class Processor(object): return result - def _LockAndExecLU(self, lu, level): + def _LockAndExecLU(self, lu, level, calc_timeout): """Execute a Logical Unit, with the needed locks. This is a recursive function that starts locking the given level, and @@ -129,129 +350,171 @@ class Processor(object): given LU and its opcodes. """ - if level in lu.needed_locks: - # This gives a chance to LUs to make last-minute changes after acquiring - # locks at any preceding level. + adding_locks = level in lu.add_locks + acquiring_locks = level in lu.needed_locks + if level not in locking.LEVELS: + if self._cbs: + self._cbs.NotifyStart() + + result = self._ExecLU(lu) + + elif adding_locks and acquiring_locks: + # We could both acquire and add locks at the same level, but for now we + # don't need this, so we'll avoid the complicated code needed. + raise NotImplementedError("Can't declare locks to acquire when adding" + " others") + + elif adding_locks or acquiring_locks: lu.DeclareLocks(level) - needed_locks = lu.needed_locks[level] share = lu.share_locks[level] - # This is always safe to do, as we can't acquire more/less locks than - # what was requested. - lu.needed_locks[level] = self.context.glm.acquire(level, - needed_locks, - shared=share) + try: - result = self._LockAndExecLU(lu, level + 1) + assert adding_locks ^ acquiring_locks, \ + "Locks must be either added or acquired" + + if acquiring_locks: + # Acquiring locks + needed_locks = lu.needed_locks[level] + + acquired = self._AcquireLocks(level, needed_locks, share, + calc_timeout()) + + if acquired is None: + raise _LockAcquireTimeout() + + else: + # Adding locks + add_locks = lu.add_locks[level] + lu.remove_locks[level] = add_locks + + try: + self.context.glm.add(level, add_locks, acquired=1, shared=share) + except errors.LockError: + raise errors.OpPrereqError( + "Couldn't add locks (%s), probably because of a race condition" + " with another job, who added them first" % add_locks, + errors.ECODE_FAULT) + + acquired = add_locks + + try: + lu.acquired_locks[level] = acquired + + result = self._LockAndExecLU(lu, level + 1, calc_timeout) + finally: + if level in lu.remove_locks: + self.context.glm.remove(level, lu.remove_locks[level]) finally: - if lu.needed_locks[level]: + if self.context.glm.is_owned(level): self.context.glm.release(level) + else: - result = self._ExecLU(lu) + result = self._LockAndExecLU(lu, level + 1, calc_timeout) return result - def ExecOpCode(self, op, feedback_fn): + def ExecOpCode(self, op, cbs): """Execute an opcode. - Args: - op: the opcode to be executed + @type op: an OpCode instance + @param op: the opcode to be executed + @type cbs: L{OpExecCbBase} + @param cbs: Runtime callbacks """ if not isinstance(op, opcodes.OpCode): raise errors.ProgrammerError("Non-opcode instance passed" " to ExecOpcode") - self._feedback_fn = feedback_fn - lu_class = self.DISPATCH_TABLE.get(op.__class__, None) - if lu_class is None: - raise errors.OpCodeUnknown("Unknown opcode") - - if lu_class.REQ_WSSTORE: - sstore = ssconf.WritableSimpleStore() - else: - sstore = ssconf.SimpleStore() - - # Acquire the Big Ganeti Lock exclusively if this LU requires it, and in a - # shared fashion otherwise (to prevent concurrent run with an exclusive LU. - self.context.glm.acquire(locking.LEVEL_CLUSTER, [locking.BGL], - shared=not lu_class.REQ_BGL) + self._cbs = cbs try: - self.exclusive_BGL = lu_class.REQ_BGL - lu = lu_class(self, op, self.context, sstore) - lu.ExpandNames() - assert lu.needed_locks is not None, "needed_locks not set by LU" - result = self._LockAndExecLU(lu, locking.LEVEL_INSTANCE) - finally: - self.context.glm.release(locking.LEVEL_CLUSTER) - self.exclusive_BGL = False + lu_class = self.DISPATCH_TABLE.get(op.__class__, None) + if lu_class is None: + raise errors.OpCodeUnknown("Unknown opcode") - return result + timeout_strategy = _LockAttemptTimeoutStrategy() - def ChainOpCode(self, op): - """Chain and execute an opcode. + while True: + try: + acquire_timeout = timeout_strategy.CalcRemainingTimeout() - This is used by LUs when they need to execute a child LU. + # Acquire the Big Ganeti Lock exclusively if this LU requires it, + # and in a shared fashion otherwise (to prevent concurrent run with + # an exclusive LU. + if self._AcquireLocks(locking.LEVEL_CLUSTER, locking.BGL, + not lu_class.REQ_BGL, acquire_timeout) is None: + raise _LockAcquireTimeout() - Args: - - opcode: the opcode to be executed + try: + lu = lu_class(self, op, self.context, self.rpc) + lu.ExpandNames() + assert lu.needed_locks is not None, "needed_locks not set by LU" - """ - if not isinstance(op, opcodes.OpCode): - raise errors.ProgrammerError("Non-opcode instance passed" - " to ExecOpcode") + try: + return self._LockAndExecLU(lu, locking.LEVEL_INSTANCE, + timeout_strategy.CalcRemainingTimeout) + finally: + if self._ec_id: + self.context.cfg.DropECReservations(self._ec_id) - lu_class = self.DISPATCH_TABLE.get(op.__class__, None) - if lu_class is None: - raise errors.OpCodeUnknown("Unknown opcode") + finally: + self.context.glm.release(locking.LEVEL_CLUSTER) - if lu_class.REQ_BGL and not self.exclusive_BGL: - raise errors.ProgrammerError("LUs which require the BGL cannot" - " be chained to granular ones.") + except _LockAcquireTimeout: + # Timeout while waiting for lock, try again + pass - assert lu_class.REQ_BGL, "ChainOpCode is still BGL-only" + timeout_strategy = timeout_strategy.NextAttempt() - if lu_class.REQ_WSSTORE: - sstore = ssconf.WritableSimpleStore() - else: - sstore = ssconf.SimpleStore() + finally: + self._cbs = None - #do_hooks = lu_class.HPATH is not None - lu = lu_class(self, op, self.context, sstore) - lu.CheckPrereq() - #if do_hooks: - # hm = HooksMaster(rpc.call_hooks_runner, self, lu) - # h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE) - # lu.HooksCallBack(constants.HOOKS_PHASE_PRE, - # h_results, self._feedback_fn, None) - result = lu.Exec(self._feedback_fn) - #if do_hooks: - # h_results = hm.RunPhase(constants.HOOKS_PHASE_POST) - # result = lu.HooksCallBack(constants.HOOKS_PHASE_POST, - # h_results, self._feedback_fn, result) - return result + def _Feedback(self, *args): + """Forward call to feedback callback function. + + """ + if self._cbs: + self._cbs.Feedback(*args) def LogStep(self, current, total, message): """Log a change in LU execution progress. """ - logger.Debug("Step %d/%d %s" % (current, total, message)) - self._feedback_fn("STEP %d/%d %s" % (current, total, message)) + logging.debug("Step %d/%d %s", current, total, message) + self._Feedback("STEP %d/%d %s" % (current, total, message)) - def LogWarning(self, message, hint=None): + def LogWarning(self, message, *args, **kwargs): """Log a warning to the logs and the user. - """ - logger.Error(message) - self._feedback_fn(" - WARNING: %s" % message) - if hint: - self._feedback_fn(" Hint: %s" % hint) + The optional keyword argument is 'hint' and can be used to show a + hint to the user (presumably related to the warning). If the + message is empty, it will not be printed at all, allowing one to + show only a hint. - def LogInfo(self, message): + """ + assert not kwargs or (len(kwargs) == 1 and "hint" in kwargs), \ + "Invalid keyword arguments for LogWarning (%s)" % str(kwargs) + if args: + message = message % tuple(args) + if message: + logging.warning(message) + self._Feedback(" - WARNING: %s" % message) + if "hint" in kwargs: + self._Feedback(" Hint: %s" % kwargs["hint"]) + + def LogInfo(self, message, *args): """Log an informational message to the logs and the user. """ - logger.Info(message) - self._feedback_fn(" - INFO: %s" % message) + if args: + message = message % tuple(args) + logging.info(message) + self._Feedback(" - INFO: %s" % message) + + def GetECId(self): + if not self._ec_id: + errors.ProgrammerError("Tried to use execution context id when not set") + return self._ec_id class HooksMaster(object): @@ -266,9 +529,8 @@ class HooksMaster(object): which behaves the same works. """ - def __init__(self, callfn, proc, lu): + def __init__(self, callfn, lu): self.callfn = callfn - self.proc = proc self.lu = lu self.op = lu.op self.env, node_list_pre, node_list_post = self._BuildEnv() @@ -309,48 +571,65 @@ class HooksMaster(object): env = self.env.copy() env["GANETI_HOOKS_PHASE"] = phase env["GANETI_HOOKS_PATH"] = hpath - if self.lu.sstore is not None: - env["GANETI_CLUSTER"] = self.lu.sstore.GetClusterName() - env["GANETI_MASTER"] = self.lu.sstore.GetMasterNode() + if self.lu.cfg is not None: + env["GANETI_CLUSTER"] = self.lu.cfg.GetClusterName() + env["GANETI_MASTER"] = self.lu.cfg.GetMasterNode() env = dict([(str(key), str(val)) for key, val in env.iteritems()]) return self.callfn(node_list, hpath, phase, env) - def RunPhase(self, phase): + def RunPhase(self, phase, nodes=None): """Run all the scripts for a phase. This is the main function of the HookMaster. - Args: - phase: the hooks phase to run - - Returns: - the result of the hooks multi-node rpc call + @param phase: one of L{constants.HOOKS_PHASE_POST} or + L{constants.HOOKS_PHASE_PRE}; it denotes the hooks phase + @param nodes: overrides the predefined list of nodes for the given phase + @return: the processed results of the hooks multi-node rpc call + @raise errors.HooksFailure: on communication failure to the nodes + @raise errors.HooksAbort: on failure of one of the hooks """ - if not self.node_list[phase]: + if not self.node_list[phase] and not nodes: # empty node list, we should not attempt to run this as either # we're in the cluster init phase and the rpc client part can't # even attempt to run, or this LU doesn't do hooks at all return hpath = self.lu.HPATH - results = self._RunWrapper(self.node_list[phase], hpath, phase) - if phase == constants.HOOKS_PHASE_PRE: - errs = [] - if not results: - raise errors.HooksFailure("Communication failure") - for node_name in results: - res = results[node_name] - if res is False or not isinstance(res, list): - self.proc.LogWarning("Communication failure to node %s" % node_name) - continue - for script, hkr, output in res: - if hkr == constants.HKR_FAIL: - output = output.strip().encode("string_escape") + if nodes is not None: + results = self._RunWrapper(nodes, hpath, phase) + else: + results = self._RunWrapper(self.node_list[phase], hpath, phase) + errs = [] + if not results: + msg = "Communication Failure" + if phase == constants.HOOKS_PHASE_PRE: + raise errors.HooksFailure(msg) + else: + self.lu.LogWarning(msg) + return results + for node_name in results: + res = results[node_name] + if res.offline: + continue + msg = res.fail_msg + if msg: + self.lu.LogWarning("Communication failure to node %s: %s", + node_name, msg) + continue + for script, hkr, output in res.payload: + if hkr == constants.HKR_FAIL: + if phase == constants.HOOKS_PHASE_PRE: errs.append((node_name, script, output)) - if errs: - raise errors.HooksAbort(errs) + else: + if not output: + output = "(no output)" + self.lu.LogWarning("On %s script %s failed, output: %s" % + (node_name, script, output)) + if errs and phase == constants.HOOKS_PHASE_PRE: + raise errors.HooksAbort(errs) return results def RunConfigUpdate(self): @@ -362,7 +641,5 @@ class HooksMaster(object): """ phase = constants.HOOKS_PHASE_POST hpath = constants.HOOKS_NAME_CFGUPDATE - if self.lu.sstore is None: - raise errors.ProgrammerError("Null sstore on config update hook") - nodes = [self.lu.sstore.GetMasterNode()] - results = self._RunWrapper(nodes, hpath, phase) + nodes = [self.lu.cfg.GetMasterNode()] + self._RunWrapper(nodes, hpath, phase)