[Development] Build Hotspots in the Qt build process

[Shane McIntosh]

Hi Andre,

On Feb 5, 2014, at 12:11 PM, Poenitz Andre <Andre.Poenitz at digia.com> wrote:

> Shane McIntosh [mcintosh at cs.queensu.ca] wrote:
>> Hi Qt developers!
>> 
>> My name is Shane. I’m a PhD student at Queen’s University in Canada.
>> 
>> I’ve been working on an approach for detecting build hotspots, i.e.,
>> files that not only take a long time to rebuild, but also change often. 
>> We think that these files are ideal candidates for refactoring that could 
>> shave time off of incremental builds that are really impacting software teams.
> 
> That sounds like a good idea in general. 
> 
> Looking at your list at
> 
>> http://sailhome.cs.queensu.ca/~shane/content/qt_hotspots.txt
> 
> I wonder a bit how e.g. xmlpatterns can be considered a "hotspot" 
> that according to your definition "changes often". The actual 
> code has not been changed much for a while except for occasional 
> merges and the annual bumps in copyright headers.
> 
> My gut feeling is that any refactoring there is not worthwhile.

Thanks for your perspective! I’m certainly not an expert in Qt development and appreciate your perspective. This could perhaps be due to our use of the median number of changes as the threshold for rate of change. I’ll make the full dataset available when I return to my lab shortly, so we can explore together to find the most appropriate thresholds for Qt.

>> I’m happy to provide a more detailed Qt dataset when I 
>> return to my lab next week.
> 
> It would be nice to see some reason ("numbers") why files ended
> up on the list.

I’ll definitely include that data :-)

Kind regards,
-Shane