While the OpenGL gaming performance on XMir/Mir was recently made faster thanks to composite bypass support being committed, the feature doesn't help out non-full-screen applications for rendering faster. To see where the current 2D Linux desktop performance is on Ubuntu 13.10 when using Intel graphics and enabling XMir and the Unity System Compositor, here are some new benchmarks...
September 10, 2013
2D Performance Is Improving For Ubuntu 13.10 XMir
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