pywinauto routinely takes 30s or more to find top_window()

Expected Behavior

Better performance. Is there a way to speed this up? Where is all the time going? Should I profile it to find out?

Actual Behavior

Takes 30s+ to find top_window.

Short Example of Code to Demonstrate the Problem

import pywinauto, time
myexe = "" # Full path to the .exe file I'm automating
myargs = "" # arguments to it
myapp = pywinauto.application.Application(backend="uia").start(f'{myexe} "{myargs}"')
start=time.perf_counter()
mywindow = myapp.top_window()
end=time.perf_counter()
print(f"Took {end-start}s to find top window.")

Always 30s+ for me and the app starts rapidly, it just sits there as I do for a half minute waiting for top_window() to return.

Specifications

• Pywinauto version: 0.6.8
• Python version and bitness: 3.83 64 bit
• Platform and OS: Windows 10

[TesterNick]

Thank you for your reply! Yes, it is specific for “uia” only. Win32 takes nanoseconds, no matter of build type (wich is about 1000 times faster than what we consider “normal” for “uia”). sys.coinit_flags = 2 does not help.

[TesterNick]

I’ve faced the same issue: top_window() for the release build of our app takes less than 1 second, but when it comes to debug build, the same operation takes about 40 sec while the app is completely responsive. I asked a programmer about differences and got the answer: “Debug build starts additional COM server (which opens a lot of interfaces). Allegedly, pywinauto tries each available interface to find the suitable one.” Switching off the COM server made the time of the two builds comparable.