Valve has released more information regarding its efforts to port zombie-killing shooter Left 4 Dead 2 and its Steam digital distribution platform to Linux - including the interesting fact that performance is better than under Windows.Comparing the 32-bit build of Ubuntu Linux 12.04 to the Windows 7 Service Pack 1 64-bit release, both running on a Core i7 3930K with an Nvidia GeForce GTX 680 and 32GB of RAM, the results were initially slightly disappointing: where the DirectX-powered Windows version of Left 4 Dead 2 managed an average of 270.6 frames per second, the OpenGL-powered Linux version managed just six frames per second.' the team explained in a blog post on the matter, stating that work then began on modifying the game to work better with OpenGL, the Linux kernel, and tweaking the graphics driver to help boost performance still further.As a result of changes made to the Source engine - including reducing overheads in calling OpenGL and switching to a Linux-friendly small-block heap memory allocation system - the performance rose significantly. Following the conclusion of testing, the Linux version of Left 4 Dead 2 was running at 315FPS compared to 270.6FPS on Windows.' the team explained. 'The improved performance for the OpenGL-based run compared to the DirectX-based run, the team claimed, is the result of a previously unnoticed overhead in Direct3D which adds a few microseconds to each batch. Although small, these delays soon add up - which explains the differing performance between the DirectX and OpenGL versions on Windows. '' the team added.Finally, the Valve Linux team explained that they have been working closely with Nvidia, AMD and Intel to boost graphics performance for their respective hardware under Linux. '' the team claimed - Torvalds' experiences to the contrary - 'With Valve proving that gaming on Linux can equal or better the Windows experience, more developers are likely to follow suit and pile in on the Steam for Linux launch.