Intel Glamor Acceleration Compared To SNA, UXA

For the Cairo Performance Demos, there's only UXA and SNA numbers since this was one of the test profiles where the Glamor-enabled Intel driver was being problematic.

With the Cairo Performance Demos, SNA tended to be noticeably faster than the UXA default in all of these Cairo library tests. Intel isn't quick though in moving from UXA to SNA since there's been user-disgruntling problems in the past when migrating from XAA to EXA and then EXA to UXA, particularly this last time when it came during the KMS migration and lots of user fall-out.

The move from UXA to SNA (or Glamor) is likely to be quite gradual based upon Intel comments in the past.

When using QGears2 with Qt4 on the XRender back-end, Glamor produced the fastest results. SNA didn't produce much change over UXA except for image scaling.