Question

I’ve just upgraded to the latest git repo for emacs 24 and compiled it as per instructions:
http://www.emacswiki.org/emacs/EmacsSnapshotAndDebian

It seems rather sluggish on repaints especially when resizing buffers, either vertical or horizontal.

I’m running Ubuntu 10.04 64bit on two screens at 1920×1080 using pretty decent hardware:
i7-930, 12GB DDR3 ram, Intel SSD X25M, Nvidia 8400GS 512MB DDR2.

When resizing the window I do notice that one core will max out at 100% whilst it’s trying to repaint the screen.

Are there any optimizations which I can make during compile or to my system?

If I have a really small window for emacs then it repaints fine.
Do I need a faster graphics card? Or is this not a graphics card problem, is it something emacs is doing in the background?

Here is my config options:

Configured for `x86_64-unknown-linux-gnu'.

  Where should the build process find the source code?    /home/map7/emacs/emacs
  What operating system and machine description files should Emacs use?
        `s/gnu-linux.h' and `m/amdx86-64.h'
  What compiler should emacs be built with?               gcc -g -O2
  Should Emacs use the GNU version of malloc?             yes
      (Using Doug Lea's new malloc from the GNU C Library.)
  Should Emacs use a relocating allocator for buffers?    no
  Should Emacs use mmap(2) for buffer allocation?         no
  What window system should Emacs use?                    x11
  What toolkit should Emacs use?                          GTK
  Where do we find X Windows header files?                Standard dirs
  Where do we find X Windows libraries?                   Standard dirs
  Does Emacs use -lXaw3d?                                 no
  Does Emacs use -lXpm?                                   yes
  Does Emacs use -ljpeg?                                  yes
  Does Emacs use -ltiff?                                  yes
  Does Emacs use a gif library?                           yes -lgif
  Does Emacs use -lpng?                                   yes
  Does Emacs use -lrsvg-2?                                yes
  Does Emacs use imagemagick?                             yes
  Does Emacs use -lgpm?                                   no
  Does Emacs use -ldbus?                                  yes
  Does Emacs use -lgconf?                                 yes
  Does Emacs use -lselinux?                               no
  Does Emacs use -lgnutls?                                yes
  Does Emacs use -lxml2?                                  yes
  Does Emacs use -lfreetype?                              yes
  Does Emacs use -lm17n-flt?                              yes
  Does Emacs use -lotf?                                   yes
  Does Emacs use -lxft?                                   yes
  Does Emacs use toolkit scroll bars?                     yes

Answer 1

1. Emacs 24 is sometimes slower. But it has not yet been released.

2. Your post is from 2011/02, which is an old build. Lots has changed since then. In particular, there were lots of very heavy slowdowns of the display engine due to the development of bidirectional text (bidi). Those slowdowns have largely been taken care of.

3. Bottom line: upgrade to the latest Emacs 24 prelease (#2).