[TUHS] Early Unix function calls: expensive?

Warren Toomey wkt at tuhs.org
Mon Jan 4 09:35:43 AEST 2016

I just re-found a quote about Unix processes that I'd "lost". It's by
Steve Johnson:

    Dennis Ritchie encouraged modularity by telling all and sundry that
    function calls were really, really cheap in C. Everybody started
    writing small functions and modularizing. Years later we found out
    that function calls were still expensive on the PDP-11, and VAX code
    was often spending 50% of its time in the CALLS instruction. Dennis
    had lied to us! But it was too late; we were all hooked...

Steve, can you recollect when you said this, was it just a quote for
Eric's book or did it come from elsewhere?

Does anybodu have a measure of the expense of function calls under Unix
on either platform?

Cheers, Warren

More information about the TUHS mailing list