tracking tasks outside the condition

unidist/config/__init__.py

@@ -13,7 +13,7 @@
     RayObjectStoreMemory,
 )
 from .backends.dask import DaskMemoryLimit, IsDaskCluster, DaskSchedulerAddress
-from .backends.mpi import IsMpiSpawnWorkers, MpiHosts, MpiPickleThreshold, BackOff
+from .backends.mpi import IsMpiSpawnWorkers, MpiHosts, MpiPickleThreshold
 from .parameter import ValueSource
 
 __all__ = [
@@ -31,5 +31,4 @@
     "MpiHosts",
     "ValueSource",
     "MpiPickleThreshold",
-    "BackOff",
 ]

unidist/config/backends/mpi/__init__.py

@@ -4,6 +4,6 @@
 
 """Config entities specific for MPI backend which can be used for unidist behavior tuning."""
 
-from .envvars import IsMpiSpawnWorkers, MpiHosts, MpiPickleThreshold, BackOff
+from .envvars import IsMpiSpawnWorkers, MpiHosts, MpiPickleThreshold
 
-__all__ = ["IsMpiSpawnWorkers", "MpiHosts", "MpiPickleThreshold", "BackOff"]
+__all__ = ["IsMpiSpawnWorkers", "MpiHosts", "MpiPickleThreshold"]

unidist/config/backends/mpi/envvars.py

@@ -25,10 +25,3 @@ class MpiPickleThreshold(EnvironmentVariable, type=int):
 
     default = 1024**2 // 4  # 0.25 MiB
     varname = "UNIDIST_MPI_PICKLE_THRESHOLD"
-
-
-class BackOff(EnvironmentVariable, type=int):
-    """Backoff value for sleeping background threads when thread idle"""
-
-    default = 0.001
-    varname = "BackOff"

unidist/core/backends/mpi/core/communication.py

@@ -181,7 +181,7 @@ def mpi_send_object(comm, data, dest_rank):
     comm.send(data, dest=dest_rank)
 
 
-def mpi_isend_object(comm, data, dest_rank, tag=0):
+def mpi_isend_object(comm, data, dest_rank):
     """
     Send Python object to another MPI rank in a non-blocking way.
 
@@ -193,16 +193,13 @@ def mpi_isend_object(comm, data, dest_rank, tag=0):
         Data to send.
     dest_rank : int
         Target MPI process to transfer data.
-    tag : int
-        To recieve only data with a label.
-        Used when background thread polls for data with a specific label.
 
     Returns
     -------
     object
         A handler to MPI_Isend communication result.
     """
-    return comm.isend(data, dest=dest_rank, tag=tag)
+    return comm.isend(data, dest=dest_rank)
 
 
 def mpi_send_buffer(comm, buffer_size, buffer, dest_rank):

unidist/core/backends/mpi/core/controller/api.py

@@ -8,9 +8,7 @@
 import atexit
 import signal
 import asyncio
-import time
 from collections import defaultdict
-import threading
 
 try:
     import mpi4py
@@ -37,7 +35,6 @@
     MpiHosts,
     ValueSource,
     MpiPickleThreshold,
-    BackOff,
 )
 
 
@@ -52,49 +49,6 @@
 topology = dict()
 # The global variable is responsible for if MPI backend has already been initialized
 is_mpi_initialized = False
-# List is used to keep keep track of th threads started so they could be later joined
-threads = []
-BACKOFF = BackOff.get_value_source()
-# The global variable acts as a flag which when set true the function executing in background thread stops
-exit_flag = False
-
-
-class Backoff:
-    def __init__(self, seconds=BACKOFF):
-        self.tval = 0.0
-        self.tmax = max(float(seconds), 0.0)
-        self.tmin = self.tmax / (1 << 10)
-
-    def reset(self):
-        self.tval = 0.0
-
-    def sleep(self):
-        time.sleep(self.tval)
-        self.tval = min(self.tmax, max(self.tmin, self.tval * 2))
-
-
-class Poller(threading.Thread):
-    def __init__(self, thread_id, name, comm):
-        threading.Thread.__init__(self, daemon=True)
-        self.thread_id = thread_id
-        self.name = name
-        self.comm = comm
-
-    def run(self):
-        poll_tasks_completed(self.name, self.comm)
-
-
-def poll_tasks_completed(threadName, comm):
-    global exit_flag
-    scheduler = Scheduler.get_instance()
-    backoff = Backoff()
-    while not exit_flag:
-        if comm.iprobe(source=communication.MPIRank.MONITOR, tag=1):
-            task_completed_rank = comm.recv(source=communication.MPIRank.MONITOR, tag=1)
-            scheduler.decrement_tasks_on_worker(task_completed_rank)
-            backoff.reset()
-        else:
-            backoff.sleep()
 
 
 def init():
@@ -172,10 +126,6 @@ def init():
     mpi_state = communication.MPIState.get_instance(
         comm, comm.Get_rank(), comm.Get_size()
     )
-    # if rank == 0 and not threads and parent_comm == MPI.COMM_NULL:
-    #     thread = Poller(1, "Thread_Poll_Tasks", comm)
-    #     thread.start()
-    #     threads.append(thread)
 
     global topology
     if not topology:
@@ -229,11 +179,7 @@ def shutdown():
     -----
     Sends cancelation operation to all workers and monitor processes.
     """
-    global exit_flag, threads
-    exit_flag = True
     mpi_state = communication.MPIState.get_instance()
-    for thread in threads:
-        thread.join()
     # Send shutdown commands to all ranks
     for rank_id in range(communication.MPIRank.MONITOR, mpi_state.world_size):
         # We use a blocking send here because we have to wait for