Slow performance using glDrawElements calls with GL_UNSIGNED_BYTE indices
Submitted by Logan McNaughton
Assigned to Default DRI bug account
Original application bug report here:
This bug happens using mupen64plus (N64 emulator) and the GLideN64 graphics plugin.
The application uses VBO streaming (https://www.khronos.org/opengl/wiki/Buffer_Object_Streaming) using ARB_buffer_storage to upload the VBO data.
Multiple users that when using Mesa + r600 driver, the performance was abysmal. It turns out that converting the glDrawElementsBaseVertex calls to glDrawArrays fixed the problem.
You can see the commit that fixed the problem here: