bug#17535: 24.3.91; Problems with profiling memory

[Stefan Monnier]

>    Position cursor on "profiler-make-profile" and type "C-h f".  Emacs
>    pops up a *Help* buffer saying:
>      profiler-make-profile is a compiled Lisp function in `profiler.el'.
>      (profiler-make-profile &key TAG VERSION TYPE LOG TIMESTAMP DIFF-P)
>      This function has a compiler macro `profiler-make-profile--cmacro'.
>      Not documented.

>    Click on the "profiler.el" link in the *Help* buffer -- Emacs
>    displays an error message saying "Unable to find location in file"

Indeed.  Looks like a problem in cl-macs.el.

> 2. How to interpret the "memory profile"?  What does a line such as
>    this in the profile mean:
>   - execute-extended-command                                  973,272  20%
>    How were the 973,272 bytes counted, and what are they 20% of?  The
>    ELisp manual, where this facility is described, does not explain
>    how to interpret the profiles, and neither can I find anything
>    about that in the doc strings.

It's the number of bytes "allocated from the system" during execution of
this function.  This "allocation" is poorly defined: we don't track
allocation of individual objects but of things like cons_blocks.

>   etc.: I see no percentage numbers except 1%, 0%, and -1%.

This is just most likely a wrap-around due to too-large integers.


        Stefan