Make smart futures avoid polling.
[python_utils.git] / executors.py
index b446822945a73c7a896755fc4b509d24c3600f84..c11bd546cc3b1b0afcefff8c3215aab2707db147 100644 (file)
@@ -22,8 +22,8 @@ from overrides import overrides
 from ansi import bg, fg, underline, reset
 import argparse_utils
 import config
-from exec_utils import run_silently, cmd_in_background, cmd_with_timeout
 from decorator_utils import singleton
+from exec_utils import run_silently, cmd_in_background, cmd_with_timeout
 import histogram as hist
 
 logger = logging.getLogger(__name__)
@@ -230,8 +230,8 @@ class BundleDetails:
     pid: int
     start_ts: float
     end_ts: float
-    too_slow: bool
-    super_slow: bool
+    slower_than_local_p95: bool
+    slower_than_global_p95: bool
     src_bundle: BundleDetails
     is_cancelled: threading.Event
     was_cancelled: bool
@@ -419,21 +419,19 @@ class RemoteExecutorStatus:
                     if qworker is not None:
                         if sec > qworker[1]:
                             ret += f'{bg("red")}>💻p95{reset()} '
-                        elif sec > qworker[0]:
-                            ret += f'{fg("red")}>💻p50{reset()} '
-                    if qall is not None:
-                        if sec > qall[1] * 1.5:
-                            ret += f'{bg("red")}!!!{reset()}'
                             if details is not None:
-                                logger.debug(f'Flagging {details} for another backup')
-                                details.super_slow = True
-                        elif sec > qall[1]:
+                                details.slower_than_local_p95 = True
+                        else:
+                            if details is not None:
+                                details.slower_than_local_p95 = False
+
+                    if qall is not None:
+                        if sec > qall[1]:
                             ret += f'{bg("red")}>∀p95{reset()} '
                             if details is not None:
-                                logger.debug(f'Flagging {details} for a backup')
-                                details.too_slow = True
-                        elif sec > qall[0]:
-                            ret += f'{fg("red")}>∀p50{reset()}'
+                                details.slower_than_global_p95 = True
+                        else:
+                            details.slower_than_global_p95 = False
                     ret += '\n'
         return ret
 
@@ -451,7 +449,6 @@ class RemoteExecutorStatus:
 
 class RemoteWorkerSelectionPolicy(ABC):
     def register_worker_pool(self, workers):
-        random.seed()
         self.workers = workers
 
     @abstractmethod
@@ -467,12 +464,14 @@ class RemoteWorkerSelectionPolicy(ABC):
 
 
 class WeightedRandomRemoteWorkerSelectionPolicy(RemoteWorkerSelectionPolicy):
+    @overrides
     def is_worker_available(self) -> bool:
         for worker in self.workers:
             if worker.count > 0:
                 return True
         return False
 
+    @overrides
     def acquire_worker(
             self,
             machine_to_avoid = None
@@ -499,12 +498,14 @@ class RoundRobinRemoteWorkerSelectionPolicy(RemoteWorkerSelectionPolicy):
     def __init__(self) -> None:
         self.index = 0
 
+    @overrides
     def is_worker_available(self) -> bool:
         for worker in self.workers:
             if worker.count > 0:
                 return True
         return False
 
+    @overrides
     def acquire_worker(
             self,
             machine_to_avoid: str = None
@@ -551,6 +552,8 @@ class RemoteExecutor(BaseExecutor):
         )
         self.status = RemoteExecutorStatus(self.worker_count)
         self.total_bundles_submitted = 0
+        self.backup_lock = threading.Lock()
+        self.last_backup = None
 
     def is_worker_available(self) -> bool:
         return self.policy.is_worker_available()
@@ -588,37 +591,84 @@ class RemoteExecutor(BaseExecutor):
 
             # Look for bundles to reschedule.
             num_done = len(self.status.finished_bundle_timings)
-            if num_done > 7 or (num_done > 5 and self.is_worker_available()):
-                for worker, bundle_uuids in self.status.in_flight_bundles_by_worker.items():
-                    for uuid in bundle_uuids:
-                        bundle = self.status.bundle_details_by_uuid.get(uuid, None)
-                        if (
-                                bundle is not None and
-                                bundle.too_slow and
-                                bundle.src_bundle is None and
-                                config.config['executors_schedule_remote_backups']
-                        ):
-                            self.consider_backup_for_bundle(bundle)
-
-    def consider_backup_for_bundle(self, bundle: BundleDetails) -> None:
-        assert self.status.lock.locked()
-        if (
-            bundle.too_slow
-            and len(bundle.backup_bundles) == 0       # one backup per
-        ):
-            msg = f"*** Rescheduling {bundle} (first backup) ***"
-            logger.debug(msg)
-            self.schedule_backup_for_bundle(bundle)
-            return
-        elif (
-                bundle.super_slow
-                and len(bundle.backup_bundles) < 2    # two backups in dire situations
-                and self.status.total_idle() > 4
-        ):
-            msg = f"*** Rescheduling {bundle} (second backup) ***"
-            logger.debug(msg)
-            self.schedule_backup_for_bundle(bundle)
-            return
+            num_idle_workers = self.worker_count - self.task_count
+            now = time.time()
+            if (
+                    config.config['executors_schedule_remote_backups']
+                    and num_done > 2
+                    and num_idle_workers > 1
+                    and (self.last_backup is None or (now - self.last_backup > 1.0))
+                    and self.backup_lock.acquire(blocking=False)
+            ):
+                try:
+                    assert self.backup_lock.locked()
+
+                    bundle_to_backup = None
+                    best_score = None
+                    for worker, bundle_uuids in self.status.in_flight_bundles_by_worker.items():
+                        # Prefer to schedule backups of bundles on slower machines.
+                        base_score = 0
+                        for record in self.workers:
+                            if worker.machine == record.machine:
+                                base_score = float(record.weight)
+                                base_score = 1.0 / base_score
+                                base_score *= 200.0
+                                base_score = int(base_score)
+                                break
+
+                        for uuid in bundle_uuids:
+                            bundle = self.status.bundle_details_by_uuid.get(uuid, None)
+                            if (
+                                    bundle is not None
+                                    and bundle.src_bundle is None
+                                    and bundle.backup_bundles is not None
+                            ):
+                                score = base_score
+
+                                # Schedule backups of bundles running longer; especially those
+                                # that are unexpectedly slow.
+                                start_ts = self.status.start_per_bundle[uuid]
+                                if start_ts is not None:
+                                    runtime = now - start_ts
+                                    score += runtime
+                                    logger.debug(f'score[{bundle}] => {score}  # latency boost')
+
+                                    if bundle.slower_than_local_p95:
+                                        score += runtime / 2
+                                        logger.debug(f'score[{bundle}] => {score}  # >worker p95')
+
+                                    if bundle.slower_than_global_p95:
+                                        score += runtime / 2
+                                        logger.debug(f'score[{bundle}] => {score}  # >global p95')
+
+                                # Prefer backups of bundles that don't have backups already.
+                                backup_count = len(bundle.backup_bundles)
+                                if backup_count == 0:
+                                    score *= 2
+                                elif backup_count == 1:
+                                    score /= 2
+                                elif backup_count == 2:
+                                    score /= 8
+                                else:
+                                    score = 0
+                                logger.debug(f'score[{bundle}] => {score}  # {backup_count} dup backup factor')
+
+                                if (
+                                        score != 0
+                                        and (best_score is None or score > best_score)
+                                ):
+                                    bundle_to_backup = bundle
+                                    assert bundle is not None
+                                    assert bundle.backup_bundles is not None
+                                    assert bundle.src_bundle is None
+                                    best_score = score
+
+                    if bundle_to_backup is not None:
+                        self.last_backup = now
+                        logger.info(f'=====> SCHEDULING BACKUP {bundle_to_backup} (score={best_score:.1f}) <=====')
+                        self.schedule_backup_for_bundle(bundle_to_backup)
+                finally:
+                    self.backup_lock.release()
 
     def check_if_cancelled(self, bundle: BundleDetails) -> bool:
         with self.status.lock:
@@ -921,8 +971,8 @@ class RemoteExecutor(BaseExecutor):
             pid = 0,
             start_ts = time.time(),
             end_ts = 0.0,
-            too_slow = False,
-            super_slow = False,
+            slower_than_local_p95 = False,
+            slower_than_global_p95 = False,
             src_bundle = None,
             is_cancelled = threading.Event(),
             was_cancelled = False,
@@ -951,8 +1001,8 @@ class RemoteExecutor(BaseExecutor):
             pid = 0,
             start_ts = time.time(),
             end_ts = 0.0,
-            too_slow = False,
-            super_slow = False,
+            slower_than_local_p95 = False,
+            slower_than_global_p95 = False,
             src_bundle = src_bundle,
             is_cancelled = threading.Event(),
             was_cancelled = False,
@@ -967,6 +1017,7 @@ class RemoteExecutor(BaseExecutor):
     def schedule_backup_for_bundle(self,
                                    src_bundle: BundleDetails):
         assert self.status.lock.locked()
+        assert src_bundle is not None
         backup_bundle = self.create_backup_bundle(src_bundle)
         logger.debug(
             f'{backup_bundle.uuid}/{backup_bundle.fname}: Scheduling backup for execution...'
@@ -1095,16 +1146,6 @@ class DefaultExecutors(object):
                         count = 2,
                     ),
                 )
-            if self.ping('backup.house'):
-                logger.info('Found backup.house')
-                pool.append(
-                    RemoteWorkerRecord(
-                        username = 'scott',
-                        machine = 'backup.house',
-                        weight = 1,
-                        count = 4,
-                    ),
-                )
             if self.ping('kiosk.house'):
                 logger.info('Found kiosk.house')
                 pool.append(