[PyQt] help with performance issue
chambers at imageworks.com
Mon Apr 11 20:31:11 BST 2011
I'm hoping there is a PyQt historian out there that can answer this
question for me.
We have a major application that we've been unable to use anything
beyond Pyqt 4.3 due to what I think is a performance issue with
setVisible. I'd like to give an example but this is proprietary code
and I can't seem to get a simple example to exhibit the problem without
bringing in the kitchen sink, I'm working on it though. What I do have
is some cProfile numbers. It doesn't really matter what version of Qt
or python we use. (You can assume we've tested many of them over the
years) Currently we're using Qt 4.5.2 and python 2.6.4.
What we have is somewhat of a disclosure widget that when clicked will
show some data and/or more disclosure widgets. In 4.7, cProfile shows
PyQt spending a lot more time in '<built-in method setVisible>. In this
test, I clicked the "show" button once to show a large amount of data,
then clicked it again to hide it, so the number of calls to setVisible is 2.
Total Time: 0.6062
Total Time: 0.0435
The "total time" is time spent in a given function, excluding time spent
in sub functions. As you can see, there is a major discrepancy between
the total time in setVisible for 4.3 and 4.7. This translates into a
slight delay when we're opening just 1 level, but if we 'expand all' a
large structure, then it becomes very apparent something is wrong.
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