Re: igc, macOS avoiding signals

[Eli Zaretskii <eliz@gnu.org>]

> From: Gerd Möllmann <gerd.moellmann@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>,  Pip Cet <pipcet@protonmail.com>,
>   spd@toadstyle.org,  emacs-devel@gnu.org
> Date: Sat, 04 Jan 2025 09:02:20 +0100
> 
> Another thought that crossed my mind. Not that I have an idea
> how to use that, but maybe someone else has?
> 
> With the existing arrangement, a count in the profiler log means time.
> It's count * sampling-interval since SIGPROFs arrive in fixed
> intervals, ignoring details.
> 
> With the new arrangement, the intervals between samples are generally
> not fixed length. Sampling is done when we get to it. Of course when
> we get to it often enough, we are approximating fixed intervals, but
> in general a count doesn't necessarily measure time, or only to a
> degree.
> 
> Can we use that somehow?

Why does time matter?  A profile shows the percentage of the samples
that we found ourselves in every function.  Time is never of any
importance, AFAIU.  That's why the frequency of SIGPROF does not
matter very much, except for very low percent values.  IOW, the
frequency of SIGPROF can explain why we miss some functions, but
that's all.