Source code for pysph.solver.controller

''' Implement infrastructure for the solver to add various interfaces '''

from functools import wraps
import threading
try:
    from thread import LockType
except ImportError:
    from _thread import LockType
from pysph.base.particle_array import ParticleArray

import logging
logger = logging.getLogger(__name__)

[docs]class DummyComm(object): ''' A dummy MPI.Comm implementation as placeholder for for serial runs '''
[docs] def Get_size(self): ''' return the size of the comm (1) ''' return 1
[docs] def Get_rank(self): ''' return the rank of the process (0) ''' return 0
[docs] def send(self, data, pid): ''' dummy send implementation ''' self.data = data
[docs] def recv(self, pid): ''' dummy recv implementation ''' data = self.data del self.data return data
[docs] def bcast(self, data): ''' bcast (broadcast) implementation for serial run ''' return data
[docs] def gather(self, data): ''' gather implementation for serial run ''' return [data]
[docs]def synchronized(lock_or_func): ''' decorator for synchronized (thread safe) function Usage: - sync_func = synchronized(lock)(func) # sync with an existing lock - sync_func = synchronized(func) # sync with a new private lock ''' if isinstance(lock_or_func, LockType): lock = lock_or_func def synchronized_inner(func): @wraps(func) def wrapped(*args, **kwargs): with lock: return func(*args, **kwargs) return wrapped return synchronized_inner else: func = lock_or_func lock = threading.Lock() return synchronized(lock)(func)
def wrap_dispatcher(obj, meth, *args2, **kwargs2): @wraps(meth) def wrapped(*args, **kwargs): kw = {} kw.update(kwargs2) kw.update(kwargs) return meth(obj.block, *(args2+args), **kw) return wrapped
[docs]class Controller(object): ''' Controller class acts a a proxy to control the solver This is passed as an argument to the interface **Methods available**: - get -- get the value of a solver parameter - set -- set the value of a solver parameter - get_result -- return result of a queued command - pause_on_next -- pause solver thread on next iteration - wait -- wait (block) calling thread till solver is paused (call after `pause_on_next`) - cont -- continue solver thread (call after `pause_on_next`) Various other methods are also available as listed in :data:`CommandManager.dispatch_dict` which perform different functions. - The methods in CommandManager.active_methods do their operation and return the result (if any) immediately - The methods in CommandManager.lazy_methods do their later when solver thread is available and return a task-id. The result of the task can be obtained later using the blocking call `get_result()` which waits till result is available and returns the result. The availability of the result can be checked using the lock returned by `get_task_lock()` method FIXME: wait/cont currently do not work in parallel ''' def __init__(self, command_manager, block=True): super(Controller, self).__init__() self.__command_manager = command_manager self.daemon = True self.block = block self._set_methods() def _set_methods(self): for prop in self.__command_manager.solver_props: setattr(self, 'get_'+prop, wrap_dispatcher(self, self.__command_manager.dispatch, 'get', prop)) setattr(self, 'set_'+prop, wrap_dispatcher(self, self.__command_manager.dispatch, 'set', prop)) for meth in self.__command_manager.solver_methods: setattr(self, meth, wrap_dispatcher(self, self.__command_manager.dispatch, meth)) for meth in self.__command_manager.lazy_methods: setattr(self, meth, wrap_dispatcher(self, self.__command_manager.dispatch, meth)) for meth in self.__command_manager.active_methods: setattr(self, meth, wrap_dispatcher(self, self.__command_manager.dispatch, meth))
[docs] def get(self, name): ''' get a solver property; returns immediately ''' return self.__command_manager.dispatch(self.block, 'get', name)
[docs] def set(self, name, value): ''' set a solver property; returns immediately; ''' return self.__command_manager.dispatch(self.block, 'set', name, value)
[docs] def pause_on_next(self): ''' pause the solver thread on next iteration ''' return self.__command_manager.pause_on_next()
[docs] def wait(self): ''' block the calling thread until the solver thread pauses call this only after calling the `pause_on_next` method to tell the controller to pause the solver thread''' self.__command_manager.wait() return True
def get_prop_names(self): return list(self.__command_manager.solver_props)
[docs] def cont(self): ''' continue solver thread after it has been paused by `pause_on_next` call this only after calling the `pause_on_next` method ''' return self.__command_manager.cont()
[docs] def get_result(self, task_id): ''' get the result of a previously queued command ''' return self.__command_manager.get_result(task_id)
[docs] def set_blocking(self, block): ''' set the blocking mode to True/False In blocking mode (block=True) all methods other than getting of solver properties block until the command is executed by the solver and return the results. The blocking time can vary depending on the time taken by solver per iteration and the command_interval In non-blocking mode, these methods queue the command for later and return a string corresponding to the task_id of the operation. The result can be later obtained by a (blocking) call to get_result with the task_id as argument ''' if block != self.block: self.block = block self._set_methods() return self.block
[docs] def get_blocking(self): ''' get the blocking mode ( True/False ) ''' return self.block
def ping(self): return True
[docs]def on_root_proc(f): ''' run the decorated function only on the root proc ''' @wraps(f) def wrapper(self, *args, **kwds): if self.comm.Get_rank()==0: return f(self, *args, **kwds) return wrapper
[docs]def in_parallel(f): ''' return a list of results of running decorated function on all procs ''' @wraps(f) def wrapper(self, *args, **kwds): return self.comm.gather(f(self, *args, **kwds)) return wrapper
[docs]class CommandManager(object): ''' Class to manage and synchronize commands from various Controllers ''' solver_props = set(('t', 'tf', 'dt', 'count', 'pfreq', 'fname', 'detailed_output', 'output_directory', 'command_interval')) solver_methods = set(('dump_output',)) lazy_methods = set(('get_particle_array_names', 'get_named_particle_array', 'get_particle_array_combined', 'get_particle_array_from_procs')) active_methods = set(('get_status', 'get_task_lock', 'set_log_level')) def __init__(self, solver, comm=None): if comm is not None: self.comm = comm self.rank = comm.Get_rank() else: try: self.comm = solver.particles.cell_manager.parallel_controller.comm except AttributeError: self.comm = DummyComm() self.rank = 0 logger.debug('CommandManager: using comm: %s'%self.comm) self.solver = solver self.interfaces = [] self.func_dict = {} self.rlock = threading.RLock() self.res_lock = threading.Lock() self.plock = threading.Condition() self.qlock = threading.Condition() # queue lock self.queue = [] self.queue_dict = {} self.queue_lock_map = {} self.results = {} self.pause = set([])
[docs] @on_root_proc def add_interface(self, callable, block=True): ''' Add a callable interface to the controller The callable must accept an Controller instance argument. The callable is called in a new thread of its own and it can do various actions with methods defined on the Controller instance passed to it The new created thread is set to daemon mode and returned ''' logger.debug('adding_interface: %s'%callable) control = Controller(self, block) thr = threading.Thread(target=callable, args=(control,)) thr.daemon = True thr.start() return thr
[docs] def add_function(self, callable, interval=1): ''' add a function to to be called every `interval` iterations ''' l = self.func_dict[interval] = self.func_dict.get(interval, []) l.append(callable)
[docs] def execute_commands(self, solver): ''' called by the solver after each timestep ''' # TODO: first synchronize all the controllers in different processes # using mpi self.sync_commands() with self.qlock: self.run_queued_commands() if self.rank == 0: logger.debug('control handler: count=%d'%solver.count) for interval in self.func_dict: if solver.count%interval == 0: for func in self.func_dict[interval]: func(solver) self.wait_for_cmd()
[docs] def wait_for_cmd(self): ''' wait for command from any interface ''' with self.qlock: while self.pause: with self.plock: self.plock.notify_all() self.qlock.wait() self.run_queued_commands()
[docs] def sync_commands(self): ''' send the pending commands to all the procs in parallel run ''' self.queue_dict, self.queue, self.pause = self.comm.bcast((self.queue_dict, self.queue, self.pause))
def run_queued_commands(self): while self.queue: lock_id = self.queue.pop(0) meth, args, kwargs = self.queue_dict[lock_id] with self.res_lock: try: self.results[lock_id] = self.run_command(meth, args, kwargs) finally: del self.queue_dict[lock_id] if self.comm.Get_rank()==0: self.queue_lock_map[lock_id].release() def run_command(self, cmd, args=[], kwargs={}): res = self.dispatch_dict[cmd](self, *args, **kwargs) logger.debug('controller: running_command: %s %s %s %s'%( cmd, args, kwargs, res)) return res
[docs] def pause_on_next(self): ''' pause and wait for command on the next control interval ''' if self.comm.Get_size() > 1: logger.debug('pause/continue not yet supported in parallel runs') return False with self.plock: self.pause.add(threading.current_thread().ident) self.plock.notify() return True
def wait(self): with self.plock: self.plock.wait()
[docs] def cont(self): ''' continue after a pause command ''' if self.comm.Get_size() > 1: logger.debug('pause/continue noy yet supported in parallel runs') return with self.plock: self.pause.remove(threading.current_thread().ident) self.plock.notify() with self.qlock: self.qlock.notify_all()
[docs] def get_result(self, lock_id): ''' get the result of a previously queued command ''' lock_id = int(lock_id) lock = self.queue_lock_map[lock_id] with lock: with self.res_lock: ret = self.results[lock_id] del self.results[lock_id] del self.queue_lock_map[lock_id] return ret
[docs] def get_task_lock(self, lock_id): ''' get the Lock instance associated with a command ''' return self.queue_lock_map[int(lock_id)]
[docs] def get_prop(self, name): ''' get a solver property ''' return getattr(self.solver, name)
[docs] def set_prop(self, name, value): ''' set a solver property ''' return setattr(self.solver, name, value)
[docs] def solver_method(self, name, *args, **kwargs): ''' execute a method on the solver ''' ret = getattr(self.solver, name)(*args, **kwargs) ret = self.comm.gather(ret) return ret
[docs] def get_particle_array_names(self): ''' get the names of the particle arrays ''' return [pa.name for pa in self.solver.particles]
def get_named_particle_array(self, name, props=None): for pa in self.solver.particles: if pa.name == name: if props: return [getattr(pa, p) for p in props if hasattr(pa, p)] else: return pa
[docs] def get_particle_array_index(self, name): ''' get the index of the named particle array ''' for i,pa in enumerate(self.solver.particles): if pa.name == name: return i
[docs] def get_particle_array_from_procs(self, idx, procs=None): ''' get particle array at index from all processes specifying processes is currently not implemented ''' if procs is None: procs = list(range(self.comm.size)) pa = self.solver.particles[idx] pas = self.comm.gather(pa) return pas
[docs] def get_particle_array_combined(self, idx, procs=None): ''' get a single particle array with combined data from all procs specifying processes is currently not implemented ''' if procs is None: procs = list(range(self.comm.size)) pa = self.solver.particles[idx] pas = self.comm.gather(pa) pa = ParticleArray(name=pa.name) for p in pas: pa.append_parray(p) return pa
[docs] def get_status(self): ''' get the status of the controller ''' return 'commands queued: %d'%len(self.queue)
[docs] def set_log_level(self, level): ''' set the logging level ''' logger.setLevel(level)
dispatch_dict = {'get':get_prop, 'set':set_prop} for meth in solver_methods: dispatch_dict[meth] = solver_method for meth in lazy_methods: dispatch_dict[meth] = locals()[meth] for meth in active_methods: dispatch_dict[meth] = locals()[meth]
[docs] @synchronized def dispatch(self, block, meth, *args, **kwargs): ''' execute/queue a command with specified arguments ''' if meth in self.dispatch_dict: if meth=='get' or meth=='set': prop = args[0] if prop not in self.solver_props: raise RuntimeError('Invalid dispatch on method: %s with ' 'non-existant property: %s '%(meth,prop)) if block or meth=='get' or meth in self.active_methods: logger.debug('controller: immediate dispatch(): %s %s %s'%( meth, args, kwargs)) return self.dispatch_dict[meth](self, *args, **kwargs) else: lock = threading.Lock() lock.acquire() lock_id = id(lock) with self.qlock: self.queue_lock_map[lock_id] = lock self.queue_dict[lock_id] = (meth, args, kwargs) self.queue.append(lock_id) logger.debug('controller: dispatch(%d): %s %s %s'%( lock_id, meth, args, kwargs)) return str(lock_id) else: raise RuntimeError('Invalid dispatch on method: '+meth)