Re: c-mode eats resources?

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Paul Pogonyshev wrote:

   Apparently, C mode constantly uses processor time even nothing is
   done in the buffer.  E.g. if I open a C file in Emacs and go to a
   different desktop and start `top' there, it shows Emacs in the
   first few lines with 3--7% usage of CPU.  This cannot be right.
   Can anybody reproduce this?

Not really.  After visiting a large file in C mode, I see some CPU
time being used, probably to fontify the buffer, but it eventually
stops after using only a very few seconds total time (four for alloc.c
and maybe those four seconds were not even all used for C mode).

Did you customize font-lock related stuff to use potentially
inefficient regexps?

You could do `C-h v' on both timer-list and timer-idle-list to see
what you have running.

Sincerely,

Luc.