commit fe16d6d8a82e53cd62b9bdda577e79b2f6e666d9
Author: juga0 <juga(a)riseup.net>
Date: Tue Jan 8 15:59:00 2019 +0000
scanner: catch SIGINT in the main loop
also split main function into an extra main_loop function to be
able to stop the threads after they have started.
Also check end event in the mean loop and before starting to
measure a new relay.
Fixes bug #28869. Bugfix v0.1.0.
---
sbws/core/scanner.py | 115 ++++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 90 insertions(+), 25 deletions(-)
diff --git a/sbws/core/scanner.py b/sbws/core/scanner.py
index 7c2a937..166ce5d 100644
--- a/sbws/core/scanner.py
+++ b/sbws/core/scanner.py
@@ -354,6 +354,88 @@ def result_putter_error(target):
return closure
+def main_loop(args, conf, controller, relay_list, circuit_builder, result_dump,
+ relay_prioritizer, destinations, max_pending_results, pool):
+ """Starts and reuse the threads that measure the relays forever.
+
+ It starts a loop that will be run while there is not and event signaling
+ that sbws is stopping (because of SIGTERM or SIGINT).
+
+ Then, it starts a second loop with an ordered list (generator) of relays
+ to measure that might a subset of all the current relays in the Network.
+
+ For every relay, it starts a new thread which runs ``measure_relay`` to
+ measure the relay until there are ``max_pending_results`` threads.
+ After that, it will reuse a thread that has finished for every relay to
+ measure.
+ It is the the pool method ``apply_async`` which starts or reuse a thread.
+ This method returns an ``ApplyResult`` immediately, which has a ``ready``
+ methods that tells whether the thread has finished or not.
+
+ When the thread finish, ie. ``ApplyResult`` is ``ready``, it triggers
+ ``result_putter`` callback, which put the ``Result`` in ``ResultDump``
+ queue and complete immediately.
+
+ ``ResultDump`` thread (started before and out of this function) will get
+ the ``Result`` from the queue and write it to disk, so this doesn't block
+ the measurement threads.
+
+ If there was an exception not catched by ``measure_relay``, it will call
+ instead ``result_putter_error``, which logs the error and complete
+ immediately.
+
+ Before iterating over the next relay, it waits (non blocking, since it
+ happens in the main thread) until one of the ``max_pending_results``
+ threads has finished.
+
+ This is not needed, since otherwise async_result will queue the relays to
+ measure in order and won't start reusing a thread to measure a relay until
+ other thread has finished. But it makes the logic a bit more sequential.
+
+ Before the outer loop iterates, it also waits (again non blocking) that all
+ the ``Results`` are ready.
+ This avoid to start measuring the same relay which might still being
+ measured.
+
+ """
+ pending_results = []
+ # Do not start a new loop if sbws is stopping.
+ while not settings.end_event.is_set():
+ log.debug("Starting a new measurement loop.")
+ num_relays = 0
+ loop_tstart = time.time()
+ for target in relay_prioritizer.best_priority():
+ # Don't start measuring a relay if sbws is stopping.
+ if settings.end_event.is_set():
+ break
+ num_relays += 1
+ log.debug('Measuring %s %s', target.nickname,
+ target.fingerprint[0:8])
+ # callback and callback_err must be non-blocking
+ callback = result_putter(result_dump)
+ callback_err = result_putter_error(target)
+ async_result = pool.apply_async(
+ dispatch_worker_thread,
+ [args, conf, destinations, circuit_builder, relay_list,
+ target], {}, callback, callback_err)
+ pending_results.append(async_result)
+ # Instead of letting apply_async to queue the relays in order until
+ # a thread has finished, wait here until a thread has finished.
+ while len(pending_results) >= max_pending_results:
+ # sleep is non-blocking sine happens in the main process
+ time.sleep(5)
+ pending_results = [r for r in pending_results if not r.ready()]
+ while len(pending_results) > 0:
+ log.debug("There are %s pending measurements.",
+ len(pending_results))
+ # sleep is non-blocking sine happens in the main process
+ time.sleep(5)
+ pending_results = [r for r in pending_results if not r.ready()]
+ loop_tstop = time.time()
+ loop_tdelta = (loop_tstop - loop_tstart) / 60
+ log.debug("Measured %s relays in %s minutes", num_relays, loop_tdelta)
+
+
def run_speedtest(args, conf):
global rd, pool, controller
controller, _ = stem_utils.init_controller(
@@ -382,31 +464,14 @@ def run_speedtest(args, conf):
fail_hard(error_msg)
max_pending_results = conf.getint('scanner', 'measurement_threads')
pool = Pool(max_pending_results)
- pending_results = []
- while True:
- num_relays = 0
- loop_tstart = time.time()
- log.info("Starting a new loop to measure relays.")
- for target in rp.best_priority():
- num_relays += 1
- log.debug('Measuring %s %s', target.nickname,
- target.fingerprint[0:8])
- callback = result_putter(rd)
- callback_err = result_putter_error(target)
- async_result = pool.apply_async(
- dispatch_worker_thread,
- [args, conf, destinations, cb, rl, target],
- {}, callback, callback_err)
- pending_results.append(async_result)
- while len(pending_results) >= max_pending_results:
- time.sleep(5)
- pending_results = [r for r in pending_results if not r.ready()]
- while len(pending_results) > 0:
- time.sleep(5)
- pending_results = [r for r in pending_results if not r.ready()]
- loop_tstop = time.time()
- loop_tdelta = (loop_tstop - loop_tstart) / 60
- log.info("Measured %s relays in %s minutes", num_relays, loop_tdelta)
+
+ try:
+ main_loop(args, conf, controller, rl, cb, rd, rp, destinations,
+ max_pending_results, pool)
+ except KeyboardInterrupt:
+ log.info("Interrupted by the user.")
+ finally:
+ stop_threads(signal.SIGINT, None)
def gen_parser(sub):