From a3162633773ce5efd3b1cc459df147c93877d953 Mon Sep 17 00:00:00 2001 From: Zac Medico Date: Tue, 7 Feb 2012 11:40:55 -0800 Subject: PollScheduler: timeouts regardless of IO events Now PollScheduler will execute timeouts predictably, even when there no IO events being generated. This allows the Scheduler's display updates to be handled via timeout_add. --- pym/_emerge/JobStatusDisplay.py | 10 ++++--- pym/_emerge/PollScheduler.py | 59 ++++++++++++++++++++++++++++++++++------- pym/_emerge/Scheduler.py | 46 +++----------------------------- 3 files changed, 59 insertions(+), 56 deletions(-) diff --git a/pym/_emerge/JobStatusDisplay.py b/pym/_emerge/JobStatusDisplay.py index 877a0c963..d84d1b060 100644 --- a/pym/_emerge/JobStatusDisplay.py +++ b/pym/_emerge/JobStatusDisplay.py @@ -209,24 +209,26 @@ class JobStatusDisplay(object): def display(self): """ Display status on stdout, but only if something has - changed since the last call. + changed since the last call. This always returns True, + for continuous scheduling via timeout_add. """ if self.quiet: - return + return True current_time = time.time() time_delta = current_time - self._last_display_time if self._displayed and \ not self._changed: if not self._isatty: - return + return True if time_delta < self._min_display_latency: - return + return True self._last_display_time = current_time self._changed = False self._display_status() + return True def _display_status(self): # Don't use len(self._completed_tasks) here since that also diff --git a/pym/_emerge/PollScheduler.py b/pym/_emerge/PollScheduler.py index fd573592a..519a3700d 100644 --- a/pym/_emerge/PollScheduler.py +++ b/pym/_emerge/PollScheduler.py @@ -43,6 +43,7 @@ class PollScheduler(object): # Increment id for each new handler. self._event_handler_id = 0 self._timeout_handlers = {} + self._timeout_interval = None self._poll_obj = create_poll_instance() self._polling = False self._scheduling = False @@ -142,18 +143,51 @@ class PollScheduler(object): return True def _poll(self, timeout=None): - """ - All poll() calls pass through here. The poll events - are added directly to self._poll_event_queue. - In order to avoid endless blocking, this raises - StopIteration if timeout is None and there are - no file descriptors to poll. - """ if self._polling: return self._polling = True try: - self._do_poll(timeout=timeout) + if self._timeout_interval is None: + self._run_timeouts() + self._do_poll(timeout=timeout) + + elif timeout is None: + while True: + self._run_timeouts() + previous_count = len(self._poll_event_queue) + self._do_poll(timeout=self._timeout_interval) + if previous_count != len(self._poll_event_queue): + break + + elif timeout <= self._timeout_interval: + self._run_timeouts() + self._do_poll(timeout=timeout) + + else: + remaining_timeout = timeout + start_time = time.time() + while True: + self._run_timeouts() + # _timeout_interval can change each time + # _run_timeouts is called + min_timeout = remaining_timeout + if self._timeout_interval is not None and \ + self._timeout_interval < min_timeout: + min_timeout = self._timeout_interval + + previous_count = len(self._poll_event_queue) + self._do_poll(timeout=min_timeout) + if previous_count != len(self._poll_event_queue): + break + elapsed_time = time.time() - start_time + if elapsed_time < 0: + # The system clock has changed such that start_time + # is now in the future, so just assume that the + # timeout has already elapsed. + break + remaining_timeout = timeout - 1000 * elapsed_time + if remaining_timeout <= 0: + break finally: self._polling = False @@ -165,7 +199,6 @@ class PollScheduler(object): StopIteration if timeout is None and there are no file descriptors to poll. """ - self._run_timeouts() if not self._poll_event_handlers: self._schedule() if timeout is None and \ @@ -273,6 +306,8 @@ class PollScheduler(object): self._timeout_handler_class( interval=interval, function=function, args=args, source_id=source_id, timestamp=time.time()) + if self._timeout_interval is None or self._timeout_interval < interval: + self._timeout_interval = interval return source_id def _run_timeouts(self): @@ -320,6 +355,12 @@ class PollScheduler(object): """ timeout_handler = self._timeout_handlers.pop(reg_id, None) if timeout_handler is not None: + if timeout_handler.interval == self._timeout_interval: + if self._timeout_handlers: + self._timeout_interval = \ + min(x.interval for x in self._timeout_handlers.values()) + else: + self._timeout_interval = None return True f = self._poll_event_handler_ids.pop(reg_id, None) if f is None: diff --git a/pym/_emerge/Scheduler.py b/pym/_emerge/Scheduler.py index 5b56650f3..e6f3e0e5c 100644 --- a/pym/_emerge/Scheduler.py +++ b/pym/_emerge/Scheduler.py @@ -196,6 +196,8 @@ class Scheduler(PollScheduler): self._status_display = JobStatusDisplay( xterm_titles=('notitles' not in settings.features)) + self._timeout_add(self._max_display_latency, + self._status_display.display) self._max_load = myopts.get("--load-average") max_jobs = myopts.get("--jobs") if max_jobs is None: @@ -352,50 +354,8 @@ class Scheduler(PollScheduler): gc.collect() def _poll(self, timeout=None): - self._schedule() - - if timeout is None: - while True: - if not self._poll_event_handlers: - self._schedule() - if not self._poll_event_handlers: - raise StopIteration( - "timeout is None and there are no poll() event handlers") - previous_count = len(self._poll_event_queue) - PollScheduler._poll(self, timeout=self._max_display_latency) - self._status_display.display() - if previous_count != len(self._poll_event_queue): - break - - elif timeout <= self._max_display_latency: - PollScheduler._poll(self, timeout=timeout) - if timeout == 0: - # The display is updated by _schedule() above, so it would be - # redundant to update it here when timeout is 0. - pass - else: - self._status_display.display() - - else: - remaining_timeout = timeout - start_time = time.time() - while True: - previous_count = len(self._poll_event_queue) - PollScheduler._poll(self, - timeout=min(self._max_display_latency, remaining_timeout)) - self._status_display.display() - if previous_count != len(self._poll_event_queue): - break - elapsed_time = time.time() - start_time - if elapsed_time < 0: - # The system clock has changed such that start_time - # is now in the future, so just assume that the - # timeout has already elapsed. - break - remaining_timeout = timeout - 1000 * elapsed_time - if remaining_timeout <= 0: - break + PollScheduler._poll(self, timeout=timeout) def _set_max_jobs(self, max_jobs): self._max_jobs = max_jobs -- cgit v1.2.3-1-g7c22