Re: Memory again

[Eli Zaretskii]

> Date: Wed, 07 Dec 2011 12:15:35 +0400
> From: Dmitry Antipov <address@hidden>
> 
> On 12/07/2011 11:52 AM, Eli Zaretskii wrote:
> 
> > You are, in fact, saying that fontifying a 60-MByte compilation buffer
> > creates text properties and other supporting data structures that can
> > accrue to a total of 2G bytes.  I find this extremely hard to believe.
> > A simple calculation will show that a file that has 1 million lines
> > with 5 different faces (warning, line number, column number,
> > underline, default) per line needs only a few million intervals -- how
> > can this require 2G bytes of memory?
> 
> Start fresh Emacs instance, make sure you're in *scratch*. Type M-x
> compilation-minor-mode, then eval (staying in *scratch*, of course):
> 
> (let ((x 0)) (while (< x 1000000) (insert "test:1:oops\n") (setq x (1+ x))))
> 
> Wait for completion, then see RSS. Next, kill *scratch*, M-x garbage-collect
> and see RSS again.

How is this different from compiling a C file with 1000000 #warning
directives?  What am I missing?