GIL, threads and scheduling - performance cost

[adsheehan at eircom.net]

Hi all,

Wondering if a GIL lock/unlock causes a re-schedule/contect swap when
embedding Python in a multi-threaded C/C++ app on Unix ?

If so, do I have any control or influence on this re-scheduling ?

The app suffers from serious performance degradation (compared to pure
c/C++) and high context switches that I suspect the GIL unlocking may
be aggravating ?

Thanks for any help.

Alan