Re: Performance of coroutine resume/yield

[Brian Hook <hook_l@...>]

Okay, so it sounds like they should be fairly lightweight.  I did a 
quick test using a single coroutine that was nothing more than just an 
infinite loop with a yield, and on my Pentium-M 1.5GHz I managed to 
achieve 1.54M yields/second.

Factoring out loop overhead for the benchmark, it's closer to 1.7M 
yields/second.

I then switched to a table of 1000 coroutines instead of calling the 
same coroutine over and over, and the performance dropped (including 
table iteration) to 1.23M yields/second, but factoring out the table 
iteration it climbs back up to around 1.7M yields/second.

This is using the 5.0 prebuilt binary off of the Wiki.

So it's about 880 clock cycles per resume/yield pair, which seems 
pretty reasonable to me -- that's going to be absorbed into the noise 
compared to the actual work happening in the coroutines, but if I have 
enough idling objects I _might_ be better served having an external 
guard that prevents the resume in a no-op case.

Thanks,

Brian