GNU bug report logs - #148
[Bernardo Dal Seno]: scroll-margin and scroll-preserve-screen-position cause refresh problem

Previous Next

Full log

Message #20 received at 148 <at> emacsbugs.donarmstrong.com (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Sven Joachim <svenjoac <at> gmx.de>
Cc: 148 <at> debbugs.gnu.org
Subject: Re: bug#148: [Bernardo Dal Seno]: scroll-margin and scroll-preserve-screen-position cause refresh problem
Date: Mon, 21 Apr 2008 07:44:46 -0400

>> This behavior is not a bug in itself, it's just a symptom: it means that
>> redisplay was interrupted by user input before it had time
>> to terminate.  See redisplay-dont-pause.

> Okay, maybe the submitter of the Debian bug should set
> redisplay-dont-pause to t to work around the problem.

Yes, that should work around the problem.

>> So, the problem you're reporting is that Emacs's redisplay is too slow
>> to keep up with the scrolling (which is indeed a problem).  This may of
>> course depend on the file's content and the major-mode (since part of the
>> redisplay time might be used by font-locking, for example).

> Do you have an explanation why the combination of

> (setq scroll-margin 2)
> (setq scroll-preserve-screen-position)

> slows down redisplay so much on C-v, especially if point is in the
> middle of the window?  I've never seen the problem in the default
> settings.

I do not have an explanation, no.


        Stefan

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.