Re: Major FPS drop in Unigine Heaven (native linux binary) under dual-monitor Xineram
Bumping up this report after re-testing with latest drivers ([s]295.17 <- it was typo[/s] 295.20). It seems that using GL_ARB_map_buffer_range in Xinerama setups still causes noticeable performance regression. Had this bug report been ever considered/took into account by nVIDIA devs?
P.S. And as a side note: looks like that current implementation of GL_ARB_map_buffer_range as it is available in linux nVIDIA drivers is pretty slow by itself, quick tests show that accessing framebuffer through FBOs (GL_ARB_pixel_buffer_object) or even using simple glReadPixels/dlDrawPixels seems to be much faster than using dynamic buffers access through GL_ARB_map_buffer_range. It's a show-stopper thing for any modern linux game (OilRush, for example) as it reduces the possible max FPS drastically.
Last edited by lexa2; 03-14-12 at 08:38 PM.
Reason: Typo correction.