I’m not sure whether it’s a bug in SDL, or if I’m missing something, but when using SDL_GL_SetSwapInterval with either -1 or 1 on Ubuntu, frame rate gets capped to 60fps despite using a 144 Hz display mode.
Since I dual boot and use cmake for the project, I booted to Windows and quickly compiled the same code. Got solid 144 fps there.
In both OSes, when I set SDL_GL_SetSwapInterval to 0, I get above 2000 fps.
My system:
Ubuntu 14.10 64-bit
Nvidia GeForce GTX 550 Ti, using proprietary 346.35 drivers, Sync to VBlank disabled, other than that - default settings.