select timeout

Problem:
Under some unclear conditions, but particularly if CPU load is too high, I get "select timeout" messages apparently due to video acquisition (v4l2)
Essai Workaround : 
-create or modify file /etc/modprobe.d/uvcvideoconf, insert line
options uvcvideo nodrop=1 trace=15 quirks=0x102 timeout=3000
-type sudo rmmod uvcvideo; sudo  modprobe uvcvideo
-reduce the number of cpu used by the program (here 2 instead of 4):
taskset -c 1,2 my_program


Works better but still fails after a while


Apparently this a bug of usb driver as far as I know unresolved  to date (06/12) even with recent kernels. Tried to close and reopen webcam every 3mn