Subject: bug#14616: 24.3.50; Excessive cursor movement on non-X Emacs

From: Eli Zaretskii <[email-masked]>
Date: Tue, 30 Jul 2013 19:44:44 +0300

> From: Lars Magne Ingebrigtsen <[email-masked]>
> Cc: [email-masked]
> Date: Tue, 30 Jul 2013 16:47:08 +0200
> 
> Hm...  I've just tried running it under xterm instead of the complicated
> cell phone/ssh thing, and the same excessive thing seems to happen
> there, but here I can see something being updated.  The cursor seems
> like it's being constantly redrawn -- it's "shimmering".

The cursor is not redrawn on a TTY.  What you see is, I believe, an
indication of Emacs constantly redrawing portions of the screen.  That
includes turning cursor off and on and moving it.

> Here's some of the output:
> 
> Breakpoint 3, update_frame_line (f=f@entry=0xb7fbe0, vpos=vpos@entry=23)
>     at dispnew.c:4755
> 4755	{
> $4554 = 23
> 
> Breakpoint 3, update_frame_line (f=f@entry=0xb7fbe0, vpos=24) at dispnew.c:4755
> 4755	{
> $4555 = 24

This says that we are constantly redrawing screen lines 23 and 24
(zero-based), counting from top of the frame.  Can you tell what is
(or was) displayed on those lines?  In particular, are these by chance
the mode line and the echo area, or are those in the text area of some
window?