Re: window-scroll-functions and performance

[Antoine Levitt]

15/08/11 22:28, Eli Zaretskii
>> From: Antoine Levitt <address@hidden>
>> Date: Mon, 15 Aug 2011 21:48:00 +0200
>> 
>> I'm trying to track down the cause of performance issues in erc. One
>> problem is with erc-scroll-to-bottom. Here's a simple test: emacs -Q,
>> M-x erc, accept the default, M-x erc-scrolltobottom-mode, C-l to force
>> scrolltobottom to act, M-x elp-instrument-package erc, press and
>> maintain "a" for a while, then M-x elp-results. erc-scrolltobottom gets
>> called a lot, and that causes noticeable slowdowns: display doesn't keep
>> up with input, and CPU consumption jumps. This gets my emacs to 100% CPU
>> just inserting text.
>
> Does the problem go away if you turn bidi-display-reordering off?

Nope. (though it does reduce CPU usage a bit - from 100% to 85 here)

> Does it go away if you use Emacs 23.3?

No, it's not a new bug.

> If the answer to any of these 2 questions is YES, please try to come
> up with a reproducible test case that doesn't involve erc, and I will
> take a look.

There does not seem to be many people using ERC on this list, and
consequently not a lot of work on it, it's a shame.