John <[EMAIL PROTECTED]> wrote: > >The table below shows the execution time for this code snippet as >measured by the unix command `time': > >for i in range(1000): > time.sleep(inter) > >inter execution time ideal >0 0.02 s 0 s >1e-4 4.29 s 0.1 s >1e-3 4.02 s 1 s >2e-3 4.02 s 2 s >5e-3 8.02 s 5 s > >Hence it seems like the 4 s is just overhead and that the time.sleep >method treats values below approximately 0.001 as 0. > >Is there a standard way (or slick trick) to get higher resolution? If >it is system dependent it's acceptable but not very nice :)
Consider what you're asking here. The operating system can only age the timer list and re-evaluate process ready states when a process goes into kernel mode, either by releasing the CPU or hitting the end of its time slice. In order to know that a process has reached the end of its time slice, it has to be interrupted by something, typically the timer interrupt. In order to provide 10us sleep resolution, the timer interrupt would have to fire every 10us. The overhead of handling the timer interrupt and rescheduling that often is quite significant. -- Tim Roberts, [EMAIL PROTECTED] Providenza & Boekelheide, Inc. -- http://mail.python.org/mailman/listinfo/python-list
