de alguns dias a CPU do processo xorg é de até 100%, notei que quando eu faço "glxinfo | grep render" a saída é:
Direct rendering: yes
GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
Extended renderer info (GLX_MESA_query_renderer):
OpenGL renderer string: Gallium 0.4 on llvmpipe (LLVM 4.0, 256 bits)
GL_ARB_conditional_render_inverted, GL_ARB_conservative depth,
GL