#
# Author: Alina Quereilhac <alina.quereilhac@inria.fr>
-import functools
-import logging
-import os
-import random
-import sys
-import time
-import threading
-
from nepi.util import guid
from nepi.util.parallel import ParallelRun
-from nepi.util.timefuncs import strfnow, strfdiff, strfvalid
+from nepi.util.timefuncs import tnow, tdiffsec, stabsformat, tsformat
from nepi.execution.resource import ResourceFactory, ResourceAction, \
ResourceState, ResourceState2str
from nepi.execution.scheduler import HeapScheduler, Task, TaskStatus
from nepi.execution.trace import TraceAttr
# TODO: use multiprocessing instead of threading
-# TODO: When a failure occurrs during deployment scp and ssh processes are left running behind!!
+# TODO: Allow to reconnect to a running experiment instance! (reconnect mode vs deploy mode)
+
+import functools
+import logging
+import os
+import random
+import sys
+import time
+import threading
class ECState(object):
""" State of the Experiment Controller
"""
.. class:: Class Args :
- :param exp_id: Id of the experiment
- :type exp_id: int
- :param root_dir: Root directory of the experiment
- :type root_dir: str
+ :param exp_id: Human readable identifier for the experiment scenario.
+ It will be used in the name of the directory
+ where experiment related information is stored
+ :type exp_id: str
.. note::
- This class is the only one used by the User. Indeed, the user "talks"
- only with the Experiment Controller and this latter forward to
- the different Resources Manager the order provided by the user.
-
+ An experiment, or scenario, is defined by a concrete use, behavior,
+ configuration and interconnection of resources that describe a single
+ experiment case (We call this the experiment description).
+ A same experiment (scenario) can be run many times.
+
+ The ExperimentController (EC), is the entity responsible for
+ managing an experiment instance (run). The same scenario can be
+ recreated (and re-run) by instantiating an EC and recreating
+ the same experiment description.
+
+ In NEPI, an experiment is represented as a graph of interconnected
+ resources. A resource is a generic concept in the sense that any
+ component taking part of an experiment, whether physical of
+ virtual, is considered a resource. A resources could be a host,
+ a virtual machine, an application, a simulator, a IP address.
+
+ A ResourceManager (RM), is the entity responsible for managing a
+ single resource. ResourceManagers are specific to a resource
+ type (i.e. An RM to control a Linux application will not be
+ the same as the RM used to control a ns-3 simulation).
+ In order for a new type of resource to be supported in NEPI
+ a new RM must be implemented. NEPI already provides different
+ RMs to control basic resources, and new can be extended from
+ the existing ones.
+
+ Through the EC interface the user can create ResourceManagers (RMs),
+ configure them and interconnect them, in order to describe an experiment.
+ Describing an experiment through the EC does not run the experiment.
+ Only when the 'deploy()' method is invoked on the EC, will the EC take
+ actions to transform the 'described' experiment into a 'running' experiment.
+
+ While the experiment is running, it is possible to continue to
+ create/configure/connect RMs, and to deploy them to involve new
+ resources in the experiment (this is known as 'interactive' deployment).
+
+ An experiments in NEPI is identified by a string id,
+ which is either given by the user, or automatically generated by NEPI.
+ The purpose of this identifier is to separate files and results that
+ belong to different experiment scenarios.
+ However, since a same 'experiment' can be run many times, the experiment
+ id is not enough to identify an experiment instance (run).
+ For this reason, the ExperimentController has two identifier, the
+ exp_id, which can be re-used by different ExperimentController instances,
+ and the run_id, which unique to a ExperimentController instance, and
+ is automatically generated by NEPI.
+
"""
- def __init__(self, exp_id = None, root_dir = "/tmp"):
+ def __init__(self, exp_id = None):
super(ExperimentController, self).__init__()
- # root directory to store files
- self._root_dir = root_dir
+ # Logging
+ self._logger = logging.getLogger("ExperimentController")
- # experiment identifier given by the user
- self._exp_id = exp_id or "nepi-exp-%s" % os.urandom(8).encode('hex')
+ # Run identifier. It identifies a concrete instance (run) of an experiment.
+ # Since a same experiment (same configuration) can be run many times,
+ # this id permits to identify concrete exoeriment run
+ self._run_id = tsformat()
+
+ # Experiment identifier. Usually assigned by the user
+ self._exp_id = exp_id or "exp-%s" % os.urandom(8).encode('hex')
# generator of globally unique ids
self._guid_generator = guid.GuidGenerator()
# Tasks
self._tasks = dict()
+ # RM groups
+ self._groups = dict()
+
+ # generator of globally unique id for groups
+ self._group_id_generator = guid.GuidGenerator()
+
# Event processing thread
self._cond = threading.Condition()
self._thread = threading.Thread(target = self._process)
# EC state
self._state = ECState.RUNNING
- # Logging
- self._logger = logging.getLogger("ExperimentController")
-
@property
def logger(self):
""" Return the logger of the Experiment Controller
@property
def exp_id(self):
- """ Return the experiment ID
+ """ Return the experiment id assigned by the user
+
+ """
+ return self._exp_id
+
+ @property
+ def run_id(self):
+ """ Return the experiment instance (run) identifier
"""
- exp_id = self._exp_id
- if not exp_id.startswith("nepi-"):
- exp_id = "nepi-" + exp_id
- return exp_id
+ return self._run_id
@property
def finished(self):
def wait_finished(self, guids):
""" Blocking method that wait until all the RM from the 'guid' list
- reach the state FINISHED
+ reached the state FINISHED ( or STOPPED, FAILED or RELEASED )
+
+ :param guids: List of guids
+ :type guids: list
+ """
+ return self.wait(guids)
+
+ def wait_started(self, guids):
+ """ Blocking method that wait until all the RM from the 'guid' list
+ reached the state STARTED ( or STOPPED, FINISHED, FAILED, RELEASED)
+ :param guids: List of guids
+ :type guids: list
+ """
+ return self.wait(guids, state = ResourceState.STARTED)
+
+ def wait_released(self, guids):
+ """ Blocking method that wait until all the RM from the 'guid' list
+ reached the state RELEASED (or FAILED)
+
+ :param guids: List of guids
+ :type guids: list
+ """
+ # TODO: solve state concurrency BUG and !!!!
+ # correct waited release state to state = ResourceState.FAILED)
+ return self.wait(guids, state = ResourceState.FINISHED)
+
+ def wait_deployed(self, guids):
+ """ Blocking method that wait until all the RM from the 'guid' list
+ reached the state READY (or any higher state)
+
+ :param guids: List of guids
+ :type guids: list
+ """
+ return self.wait(guids, state = ResourceState.READY)
+
+ def wait(self, guids, state = ResourceState.STOPPED):
+ """ Blocking method that waits until all the RM from the 'guid' list
+ reached state 'state' or until a failure occurs
+
:param guids: List of guids
:type guids: list
"""
if isinstance(guids, int):
guids = [guids]
- while not all([self.state(guid) in [ResourceState.FINISHED,
- ResourceState.STOPPED,
- ResourceState.FAILED] \
- for guid in guids]) and not self.finished:
- # We keep the sleep as large as possible to
- # decrese the number of RM state requests
- time.sleep(2)
-
+ # we randomly alter the order of the guids to avoid ordering
+ # dependencies (e.g. LinuxApplication RMs runing on the same
+ # linux host will be synchronized by the LinuxNode SSH lock)
+ random.shuffle(guids)
+
+ while True:
+ # If no more guids to wait for or an error occured, then exit
+ if len(guids) == 0 or self.finished:
+ break
+
+ # If a guid reached one of the target states, remove it from list
+ guid = guids[0]
+ rstate = self.state(guid)
+
+ if rstate >= state:
+ guids.remove(guid)
+ else:
+ # Debug...
+ self.logger.debug(" WAITING FOR guid %d - state is %s, required is >= %s " % (guid,
+ self.state(guid, hr = True), state))
+
+ # Take the opportunity to 'refresh' the states of the RMs.
+ # Query only the first up to N guids (not to overwhelm
+ # the local machine)
+ n = 100
+ lim = n if len(guids) > n else ( len(guids) -1 )
+ nguids = guids[0: lim]
+
+ # schedule state request for all guids (take advantage of
+ # scheduler multi threading).
+ for guid in nguids:
+ callback = functools.partial(self.state, guid)
+ self.schedule("0s", callback)
+
+ # If the guid is not in one of the target states, wait and
+ # continue quering. We keep the sleep big to decrease the
+ # number of RM state queries
+ time.sleep(4)
+
def get_task(self, tid):
""" Get a specific task
:param tid: Id of the task
:type tid: int
- :rtype: unknow
+ :rtype: Task
"""
return self._tasks.get(tid)
:param guid: Id of the task
:type guid: int
- :rtype: ResourceManager
+ :rtype: ResourceManager
"""
return self._resources.get(guid)
def resources(self):
""" Returns the list of all the Resource Manager Id
- :rtype: set
+ :rtype: set
+
"""
return self._resources.keys()
:param rtype: Type of the RM
:type rtype: str
- :return : Id of the RM
- :rtype: int
+ :return: Id of the RM
+ :rtype: int
"""
# Get next available guid
guid = self._guid_generator.next(guid)
:param guid: Guid of the RM
:type guid: int
- :return : List of attributes
+ :return: List of attributes
:rtype: list
"""
rm = self.get_resource(guid)
:param guid2: Second guid to connect
:type guid: ResourceManager
-
"""
rm1 = self.get_resource(guid1)
rm2 = self.get_resource(guid2)
- rm1.connect(guid2)
- rm2.connect(guid1)
+ rm1.register_connection(guid2)
+ rm2.register_connection(guid1)
- def register_condition(self, group1, action, group2, state,
+ def register_condition(self, guids1, action, guids2, state,
time = None):
- """ Registers an action START or STOP for all RM on group1 to occur
- time 'time' after all elements in group2 reached state 'state'.
+ """ Registers an action START or STOP for all RM on guids1 to occur
+ time 'time' after all elements in guids2 reached state 'state'.
- :param group1: List of guids of RMs subjected to action
- :type group1: list
+ :param guids1: List of guids of RMs subjected to action
+ :type guids1: list
:param action: Action to register (either START or STOP)
:type action: ResourceAction
- :param group2: List of guids of RMs to we waited for
- :type group2: list
+ :param guids2: List of guids of RMs to we waited for
+ :type guids2: list
:param state: State to wait for on RMs (STARTED, STOPPED, etc)
:type state: ResourceState
- :param time: Time to wait after group2 has reached status
+ :param time: Time to wait after guids2 has reached status
:type time: string
"""
- if isinstance(group1, int):
- group1 = [group1]
- if isinstance(group2, int):
- group2 = [group2]
+ if isinstance(guids1, int):
+ guids1 = [guids1]
+ if isinstance(guids2, int):
+ guids2 = [guids2]
- for guid1 in group1:
+ for guid1 in guids1:
rm = self.get_resource(guid1)
- rm.register_condition(action, group2, state, time)
+ rm.register_condition(action, guids2, state, time)
- def register_trace(self, guid, name):
+ def enable_trace(self, guid, name):
""" Enable trace
:param name: Name of the trace
:type name: str
"""
rm = self.get_resource(guid)
- rm.register_trace(name)
+ rm.enable_trace(name)
+
+ def trace_enabled(self, guid, name):
+ """ Returns True if trace is enabled
+
+ :param name: Name of the trace
+ :type name: str
+ """
+ rm = self.get_resource(guid)
+ return rm.trace_enabled(name)
def trace(self, guid, name, attr = TraceAttr.ALL, block = 512, offset = 0):
""" Get information on collected trace
"""
rm = self.get_resource(guid)
+ state = rm.state
+
if hr:
- return ResourceState2str.get(rm.state)
+ return ResourceState2str.get(state)
- return rm.state
+ return state
def stop(self, guid):
""" Stop a specific RM defined by its 'guid'
rm = self.get_resource(guid)
return rm.start()
- def set_with_conditions(self, name, value, group1, group2, state,
+ def set_with_conditions(self, name, value, guids1, guids2, state,
time = None):
""" Set value 'value' on attribute with name 'name' on all RMs of
- group1 when 'time' has elapsed since all elements in group2
+ guids1 when 'time' has elapsed since all elements in guids2
have reached state 'state'.
:param name: Name of attribute to set in RM
:param value: Value of attribute to set in RM
:type name: string
- :param group1: List of guids of RMs subjected to action
- :type group1: list
+ :param guids1: List of guids of RMs subjected to action
+ :type guids1: list
:param action: Action to register (either START or STOP)
:type action: ResourceAction
- :param group2: List of guids of RMs to we waited for
- :type group2: list
+ :param guids2: List of guids of RMs to we waited for
+ :type guids2: list
:param state: State to wait for on RMs (STARTED, STOPPED, etc)
:type state: ResourceState
- :param time: Time to wait after group2 has reached status
+ :param time: Time to wait after guids2 has reached status
:type time: string
"""
- if isinstance(group1, int):
- group1 = [group1]
- if isinstance(group2, int):
- group2 = [group2]
+ if isinstance(guids1, int):
+ guids1 = [guids1]
+ if isinstance(guids2, int):
+ guids2 = [guids2]
- for guid1 in group1:
+ for guid1 in guids1:
rm = self.get_resource(guid)
- rm.set_with_conditions(name, value, group2, state, time)
+ rm.set_with_conditions(name, value, guids2, state, time)
def stop_with_conditions(self, guid):
""" Stop a specific RM defined by its 'guid' only if all the conditions are true
"""
rm = self.get_resource(guid)
- return rm.start_with_condition()
+ return rm.start_with_conditions()
- def deploy(self, group = None, wait_all_ready = True):
- """ Deploy all resource manager in group
+ def deploy(self, guids = None, wait_all_ready = True, group = None):
+ """ Deploy all resource manager in guids list
- :param group: List of guids of RMs to deploy
- :type group: list
+ :param guids: List of guids of RMs to deploy
+ :type guids: list
:param wait_all_ready: Wait until all RMs are ready in
order to start the RMs
:type guid: int
+ :param group: Id of deployment group in which to deploy RMs
+ :type group: int
+
"""
self.logger.debug(" ------- DEPLOY START ------ ")
+ if not guids:
+ # If no guids list was indicated, all 'NEW' RMs will be deployed
+ guids = []
+ for guid in self.resources:
+ if self.state(guid) == ResourceState.NEW:
+ guids.append(guid)
+
+ if isinstance(guids, int):
+ guids = [guids]
+
+ # Create deployment group
+ new_group = False
if not group:
- group = self.resources
+ new_group = True
+ group = self._group_id_generator.next(guid)
- if isinstance(group, int):
- group = [group]
+ if group not in self._groups:
+ self._groups[group] = []
- # Before starting deployment we disorder the group list with the
+ self._groups[group].extend(guids)
+
+ # Before starting deployment we disorder the guids list with the
# purpose of speeding up the whole deployment process.
- # It is likely that the user inserted in the 'group' list closely
+ # It is likely that the user inserted in the 'guids' list closely
# resources one after another (e.g. all applications
# connected to the same node can likely appear one after another).
# This can originate a slow down in the deployment since the N
# be taken up by the same family of resources waiting for the
# same conditions (e.g. LinuxApplications running on a same
# node share a single lock, so they will tend to be serialized).
- # If we disorder the group list, this problem can be mitigated.
- #random.shuffle(group)
+ # If we disorder the guids list, this problem can be mitigated.
+ random.shuffle(guids)
def wait_all_and_start(group):
reschedule = False
- for guid in group:
- rm = self.get_resource(guid)
- if rm.state < ResourceState.READY:
+
+ # Get all guids in group
+ guids = self._groups[group]
+
+ for guid in guids:
+ if self.state(guid) < ResourceState.READY:
reschedule = True
break
self.schedule("1s", callback)
else:
# If all resources are read, we schedule the start
- for guid in group:
+ for guid in guids:
rm = self.get_resource(guid)
self.schedule("0s", rm.start_with_conditions)
- if wait_all_ready:
- # Schedule the function that will check all resources are
- # READY, and only then it will schedule the start.
- # This is aimed to reduce the number of tasks looping in the scheduler.
- # Intead of having N start tasks, we will have only one
+ if wait_all_ready and new_group:
+ # Schedule a function to check that all resources are
+ # READY, and only then schedule the start.
+ # This aimes at reducing the number of tasks looping in the
+ # scheduler.
+ # Intead of having N start tasks, we will have only one for
+ # the whole group.
callback = functools.partial(wait_all_and_start, group)
self.schedule("1s", callback)
- for guid in group:
+ for guid in guids:
rm = self.get_resource(guid)
+ rm.deployment_group = group
self.schedule("0s", rm.deploy)
if not wait_all_ready:
# schedule a stop. Otherwise the RM will stop immediately
self.schedule("2s", rm.stop_with_conditions)
+ def release(self, guids = None):
+ """ Release al RMs on the guids list or
+ all the resources if no list is specified
- def release(self, group = None):
- """ Release the elements of the list 'group' or
- all the resources if any group is specified
-
- :param group: List of RM
- :type group: list
+ :param guids: List of RM guids
+ :type guids: list
"""
- if not group:
- group = self.resources
+ if not guids:
+ guids = self.resources
- threads = []
- for guid in group:
+ for guid in guids:
rm = self.get_resource(guid)
- thread = threading.Thread(target=rm.release)
- threads.append(thread)
- thread.setDaemon(True)
- thread.start()
-
- while list(threads) and not self.finished:
- thread = threads[0]
- # Time out after 5 seconds to check EC not terminated
- thread.join(5)
- if not thread.is_alive():
- threads.remove(thread)
+ self.schedule("0s", rm.release)
+
+ self.wait_released(guids)
def shutdown(self):
""" Shutdown the Experiment Controller.
:return : The Id of the task
"""
- timestamp = strfvalid(date)
-
+ timestamp = stabsformat(date)
task = Task(timestamp, callback)
task = self._scheduler.schedule(task)
if track:
self._tasks[task.id] = task
-
+
# Notify condition to wake up the processing thread
self._notify()
def _process(self):
""" Process scheduled tasks.
+ .. note::
+
The _process method is executed in an independent thread held by the
ExperimentController for as long as the experiment is running.
Tasks are scheduled by invoking the schedule method with a target callback.
- The schedule method is givedn a execution time which controls the
+ The schedule method is given a execution time which controls the
order in which tasks are processed.
Tasks are processed in parallel using multithreading.
The environmental variable NEPI_NTHREADS can be used to control
the number of threads used to process tasks. The default value is 50.
+ Exception handling:
+
+ To execute tasks in parallel, an ParallelRunner (PR) object, holding
+ a pool of threads (workers), is used.
+ For each available thread in the PR, the next task popped from
+ the scheduler queue is 'put' in the PR.
+ Upon receiving a task to execute, each PR worker (thread) invokes the
+ _execute method of the EC, passing the task as argument.
+ This method, calls task.callback inside a try/except block. If an
+ exception is raised by the tasks.callback, it will be trapped by the
+ try block, logged to standard error (usually the console), and the EC
+ state will be set to ECState.FAILED.
+ The invocation of _notify immediately after, forces the processing
+ loop in the _process method, to wake up if it was blocked waiting for new
+ tasks to arrived, and to check the EC state.
+ As the EC is in FAILED state, the processing loop exits and the
+ 'finally' block is invoked. In the 'finally' block, the 'sync' method
+ of the PR is invoked, which forces the PR to raise any unchecked errors
+ that might have been raised by the workers.
+
"""
nthreads = int(os.environ.get("NEPI_NTHREADS", "50"))
try:
while not self.finished:
self._cond.acquire()
+
task = self._scheduler.next()
- self._cond.release()
if not task:
- # It there are not tasks in the tasks queue we need to
- # wait until a call to schedule wakes us up
- self._cond.acquire()
+ # No task to execute. Wait for a new task to be scheduled.
self._cond.wait()
- self._cond.release()
- else:
- # If the task timestamp is in the future the thread needs to wait
- # until time elapse or until another task is scheduled
- now = strfnow()
+ else:
+ # The task timestamp is in the future. Wait for timeout
+ # or until another task is scheduled.
+ now = tnow()
if now < task.timestamp:
- # Calculate time difference in seconds
- timeout = strfdiff(task.timestamp, now)
+ # Calculate timeout in seconds
+ timeout = tdiffsec(task.timestamp, now)
+
# Re-schedule task with the same timestamp
self._scheduler.schedule(task)
- # Sleep until timeout or until a new task awakes the condition
- self._cond.acquire()
+
+ task = None
+
+ # Wait timeout or until a new task awakes the condition
self._cond.wait(timeout)
- self._cond.release()
- else:
- # Process tasks in parallel
- runner.put(self._execute, task)
+
+ self._cond.release()
+
+ if task:
+ # Process tasks in parallel
+ runner.put(self._execute, task)
except:
import traceback
err = traceback.format_exc()
- self._logger.error("Error while processing tasks in the EC: %s" % err)
+ self.logger.error("Error while processing tasks in the EC: %s" % err)
self._state = ECState.FAILED
finally:
+ self.logger.debug("Exiting the task processing loop ... ")
runner.sync()
+ runner.destroy()
def _execute(self, task):
""" Executes a single task.
- If the invokation of the task callback raises an
- exception, the processing thread of the ExperimentController
- will be stopped and the experiment will be aborted.
-
:param task: Object containing the callback to execute
:type task: Task
+ .. note::
+
+ If the invokation of the task callback raises an
+ exception, the processing thread of the ExperimentController
+ will be stopped and the experiment will be aborted.
+
"""
# Invoke callback
task.status = TaskStatus.DONE
task.result = err
task.status = TaskStatus.ERROR
- self._logger.error("Error occurred while executing task: %s" % err)
+ self.logger.error("Error occurred while executing task: %s" % err)
# Set the EC to FAILED state (this will force to exit the task
# processing thread)