Runtime: work around 1s delay added when using twisted reactor's callLater.
Since wxPython4, using wxReactor from non-main thread was producing
exceptions in wxWidget's C++ code. Then reactor.run() was called from
main thread, and runtime's worker was delegating calls to reactor
with callLater(0, callable).
While this worked perfectly with wxReactor, it did introduce an unexplained
1 second delay to each worker call when using nomal linux reactors
(i.e. without wxPython). As a workaround reactor runs in a thread when using
twisted without wxPython
--- a/Beremiz_service.py Wed Sep 14 15:24:33 2022 +0200
+++ b/Beremiz_service.py Wed Oct 05 16:10:17 2022 +0200
@@ -423,7 +423,12 @@
if havewx:
from twisted.internet import wxreactor
wxreactor.install()
- from twisted.internet import reactor
+ from twisted.internet import reactor
+ reactor.registerWxApp(app)
+ else:
+ # from twisted.internet import pollreactor
+ # pollreactor.install()
+ from twisted.internet import reactor
havetwisted = True
except ImportError:
@@ -432,11 +437,6 @@
pyruntimevars = {}
-if havetwisted:
- if havewx:
- reactor.registerWxApp(app)
-
-
if havewx:
wx_eval_lock = Semaphore(0)
@@ -578,26 +578,50 @@
runtime.GetPLCObjectSingleton().AutoLoad(autostart)
-if havetwisted or havewx:
-
- waker_func = wx.CallAfter if havewx else partial(reactor.callLater,0)
+if havetwisted and havewx:
+
+ waker_func = wx.CallAfter
# This orders ui loop to signal when ready on Stdout
waker_func(print,"UI thread started successfully.")
- # worker that copes with wx and (wx)reactor
+ # interleaved worker copes with wxreactor by delegating all asynchronous
+ # calls to wx's mainloop
runtime.MainWorker.interleave(waker_func, FirstWorkerJob)
try:
- if havetwisted:
- reactor.run(installSignalHandlers=False)
- else:
- app.MainLoop
+ reactor.run(installSignalHandlers=False)
except KeyboardInterrupt:
pass
runtime.MainWorker.stop()
+elif havewx:
+
+ try:
+ app.MainLoop
+ except KeyboardInterrupt:
+ pass
+
+elif havetwisted:
+
+ ui_thread_started = Lock()
+ ui_thread_started.acquire()
+
+ reactor.callLater(0, ui_thread_started.release)
+
+ ui_thread = Thread(
+ target=partial(reactor.run, installSignalHandlers=False),
+ name="UIThread")
+ ui_thread.start()
+
+ ui_thread_started.acquire()
+ print("UI thread started successfully.")
+ try:
+ # blocking worker loop
+ runtime.MainWorker.runloop(FirstWorkerJob)
+ except KeyboardInterrupt:
+ pass
else:
try:
# blocking worker loop
@@ -618,6 +642,8 @@
if havetwisted:
reactor.stop()
+ if not havewx:
+ ui_thread.join()
elif havewx:
app.ExitMainLoop()