[Xcb] Question about xcb performance and threading support

Benoît Minisini gambas at users.sourceforge.net
Tue Feb 17 05:17:37 PST 2009


Hi,

I have currently using valgrind / callgrind & kcachegrind with the Gambas IDE 
to try to understand why QT4.4 is slower than QT3.

I noticed in the Gambas/QT4 kcachegrind output that pthread_mutex_lock and 
pthread_mutex_unlock take respectively 1.41% and 1.52% of the execution time.

The Gambas/QT3 kcachegrind output gives approximatively the same result.

I am a bit disappointed with that: using 3% of the total execution time just 
to manage threads in a library for a completely non-threaded application.

Is there a way to optimize that? For example having a single-threaded version 
of libxcb. Or is there something more complex behind that? (I guess so...)

My system is a Mandriva 2009 with libxcb 1.1.91.

Thanks in advance for any answer.

Regards,

-- 
Benoît




More information about the Xcb mailing list