Re: [PATCH] Console based mouse face highlighting.

[David Kastrup <dak@gnu.org>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Nick Roberts <nickrob@snap.net.nz>
>> Date: Tue, 15 May 2007 15:53:16 +1200
>> Cc: emacs-devel@gnu.org
>> 
>> Is cursor movement expensive on GNU/Linux?
>
> I don't think so, but in any case, it is IMO wrong to try to optimize
> this case before you actually see that it slows down redisplay.  I
> suggest to do it right first, and worry about speed afterwards, if
> needed.

"Expensive" is probably the wrong question.  With regard to CPU usage,
cursor movement on a tty will be negligible.  However, it may have
visual effects (depending on the terminal in question), and one of the
reasons for using a tty in the first place might be a lack of
bandwidth or high latency.  With regard to latency, one wants to avoid
"roundtrips", but those don't occur usually for text terminal control
sequences.  With regard to bandwidth, one might want to avoid
excessive cursor positioning, and also too many separate write calls.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum