EXA

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For the prefix, see exa.

In computing, EXA is a graphics acceleration architecture of the X.Org Server (see also X Window System) designed to replace XAA ^[1] (the XFree86 Acceleration Architecture) and to make the XRender extension more usable, with only minor changes needed to adapt XFree86 video drivers written to use XAA; it was designed by Zack Rusin and announced at LinuxTag 2005^[2] and first released with X.Org Server version 6.9/7.0.

EXA is considered a stopgap measure to improve X.Org Server performance before the server is moved entirely to OpenGL; XAA does not accelerate many 2D operations heavily used in current applications, and in particular was considered not to do enough in accelerating XRender.

EXA was adapted from KAA, the KDrive Acceleration Architecture, from the experimental Freedesktop.org Xserver. Per the initial mailing list announcement,^[3] the goals are:

1. Properly accelerate XRender;
2. Be as simple as possible.

Many XAA drivers had EXA support added for X11R6.9/7.0 and support continues to be added to more drivers. Making this transition as easy as possible was an important design consideration.^[4]

[edit] Acronym

According to the XorgGlossary,^[5] EXA is an "acceleration architecture with no well-defined acronym." Dot.kde.org called it "Eyecandy Acceleration Architecture".^[6] The driver modification guide^[4] calls it "EXcellent Architecture or Ex-kaa aXeleration Architecture or whatever."

[edit] References

1. ^ Summer coding (Zack Rusin blog entry, 3 June 2005)
2. ^ Acceleration Architecture (initial LinuxTag presentation by Zack Rusin)
3. ^ New acceleration architecture (announcement on Xorg mailing list, Zack Rusin, 25 June 2005)
4. ^ ^{a b} Adding EXA support to your X.Org video driver (Jesse Barnes)
5. ^ X.Org Wiki - Development/Documentation/Glossary
6. ^ New Acceleration Architecture for X.org (dot.kde.org, 28 June 2005)

[edit] External links

• ExaStatus (X.Org)
• Freedesktop.org