EXA
In the
X Window System, in the
X.Org Server,
EXA is a graphics acceleration architecture to make the
XRender extension more usable, with only minor changes needed to adapt
XFree86 video drivers written to use XAA (the
XFree86 Acceleration Architecture). It was designed by
Zack Rusin, announced at
LinuxTag 2005 [
1] and first released with X.Org Server version 6.9/7.0.
EXA is designed to replace XAA, which does not accelerate many 2D operations heavily used in current applications, and in particular was considered not to do enough in accelerating XRender. EXA is considered a stopgap measure to improve X.Org Server performance before the server is moved entirely to
OpenGL.
EXA was adapted from KAA, the
Kdrive Acceleration Architecture, from the experimental
Freedesktop.org Xserver. Per the initial mailing list announcement, the goals are:
# Properly accelerate
XRender;# Be as simple as possible.
Many XAA drivers have had EXA support added for X11R6.9/7.0. Making this transition as easy as possible was an important design consideration [
2].
According to the XorgGlossary [
3],
EXA is an
"acceleration architecture with no well-defined acronym." Dot.kde.org called it "Eyecandy Acceleration Architecture" [
4]. The driver modification guide [
5] calls it "EXcellent Architecture or Ex-kaa aXeleration Architecture or whatever."
*
Acceleration Architecture (initial LinuxTag presentation by Zack Rusin)
*
Summer coding (Zack Rusin
blog entry,
3 June 2005)
*
New acceleration architecture (announcement on Xorg mailing list, Zack Rusin,
25 June 2005)
*
New Acceleration Architecture for X.org (dot.kde.org,
28 June 2005)
*
Adding EXA support to your X.Org video driver (
Jesse Barnes)
*
ExaStatus (X.Org)
*
Freedesktop.org
