Procedure overhead

[Buck Calabro <Buck.Calabro@xxxxxxxxxxxx>]

>The longest time factor I had in using subprocedures
>was allowing huge strings.  And it specifically
>had to do with using XLATE.  My subprocedure
>would capitalize up to a 32,000 byte string.

I did some timings on %trim that were frightening.  I found that defining
the strings as 'varying' made a world of difference (making performance
scream!)

I ran this code:

d loopLimit       s             10u 0 inz(100000)
d start           s               z
d stop            s               z
d duration        s             10i 0

dNOP              pr

 * inline
c                   time                    start
c                   do        loopLimit
c                   enddo
c                   time                    stop
c     stop          subdur    start         duration:*ms
c     duration      dsply

 * procedure
c                   time                    start
c                   do        loopLimit
c                   callp     NOP
c                   enddo
c                   time                    stop
c     stop          subdur    start         duration:*ms
c     duration      dsply

c                   seton                                        lr

pNOP              b
dNOP              pi
p                 e

And got these results:
 21 ms
248 ms

So yes, the procedure does indeed have overhead - a full order of magnitude
worth.  But for a hundred thousand iterations on an old 620 2 tenths of a
second isn't really burdensome.  Like Bob says, if you have a terribly
time-critical function, move it inline (at least use /COPY!) but for the
vast majority of applications, I can't imagine that this miniscule amount of
overhead is going to be unreasonable, despite the large percentage change.
  --buck