[pygtk] PyGTK and threading

[Walter Leibbrandt]

Vláďa wrote:
> ... I'm absolutely new to threads, I understand what are they good for, but unfortunately I have 
> almost no idea about the consequences and the problems they bring. ...
>   
Seeing as you're "absolutely new to threads", I'll just make sure that 
you are aware of the inherent limitations of threading in Python. But 
seeing as you've read a few tutorials/articles, you probably have come 
across the plight on parallelism in Python: the GIL (Global Interpreter 
Lock). Basically what that implies is that, even though multi-threading 
is still possible, you won't gain much in the way of performance (the 
Python interpreter can still only execute one command at a time). I've 
read somewhere (can't remember where... possibly a blog) that Python 
threading is basically only useful for getting around blocking 
situations, like waiting for input.

Besides the GIL, it is very clear that Gtk+ itself was not designed to 
be used in multi-threaded applications. This has become obvious to me 
after trading in Gtk# for PyGtk and realizing that the exact same 
problems exist. That said, you might want to take a look at 
http://www.mono-project.com/Responsive_Applications. Although that 
article is written for use with Gtk#, the (supported) concepts are the 
same for PyGtk.

Personally, I have not tried to multi-thread an app with PyGtk, but I 
can assure you that it was a mess with Gtk#. :P

Good luck!

Walter

-- 
Walter Leibbrandt                  http://translate.org.za/blogs/walter
Software Developer                                  +27 12 460 1095 (w)
Translate.org.za

Recent blogs:
* Auto-completion and auto-correction for Gtk+ widgets
http://www.translate.org.za/blogs/walter/en/content/auto-completion-and-auto-correction-gtk-widgets
* Gtk+ Tip of the Day: Modifying the subject of an event being processed
* Spelt 0.1rc2 released