emacs-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Loading souce Elisp faster


From: Stephen J. Turnbull
Subject: Re: Loading souce Elisp faster
Date: Wed, 27 Feb 2013 11:22:10 +0900

Richard Stallman writes:

 > If we could manage to speed up the entire code conversion stage,
 > that would be a much bigger improvement, helping every user.

I suppose anything's possible, but when this issue came up for us
careful measurements showed that code conversion itself causes delays
only if the whole file is already in memory -- otherwise code
conversion throughput is at least as high as disk I/O throughput.  I
don't recall the details, that was done in the last millennium.

Again, for XEmacs comparisons of find-file-literally to anything else
(in particular, file-file) tell you very little about coding
conversion speed because find-file does a lot of processing in Lisp
that find-file-literally does not.  (files.el is nowhere near big
enough to amortize that cost; I would go for a file in the 10MB range
or bigger.)  I believe that Emacs is the same.

While presumably hooks and file handlers aren't actually called in the
tests reported in this thread, coding *detection* is costly, as it
involves a couple of extra seeks and reads on disk.  This is exactly
what the proposal to default Lisp files to UTF-8 addresses.



reply via email to

[Prev in Thread] Current Thread [Next in Thread]