Re: M-x compile gets progressively slower when using emacs with gdb

[Richard Stallman]

When something gets progressively slower, a useful debugging technique
is to run Emacs under GDB and stop it occasionally while it is doing
the operation when it has become quite slow.  Each time, make a C
backtrace (using the backtrace command in GDB) and a Lisp backtrace
(using the xbacktrace command).  Eventually you will see a pattern
that occurs frequently, and that will show where the slowness is.