Mesa 10.5-devel Brings Some Intel Haswell HD Graphics Changes Over Mesa 10.3
The Counter-Strike: Global Offensive performance for the Intel HD Graphics 4600 was rather unchanged between Mesa 10.3.0 and 10.5-devel.
OpenArena, meanwhile, saw a slight improvement in performance with the newer Mesa Git code.
Mesa 10.3 and 10.5-devel both expose OpenGL 3.3 compliance for the Intel i965 Mesa driver, although OpenGL 4.0~4.2 support is very close in Git. For the Tesseract game, there's a performance drop using Git master.