Beh?! Non vedo scritto qualcosa tipo: "Dovremmo iniziare a sviluppare su Linux e solo dopo portare su Windows".
2012/8/3 Open: libera aperta anonima senza censura <[email protected]>: > http://blogs.valvesoftware.com/linux/faster-zombies/ > > One factor in creating a good gaming experience is throughput. This post > discusses some of what we’ve learned about the performance of our games > running on Linux. > As any software developer can tell you, performance is a complicated > issue. In the interests of simplicity, we’ll concern ourselves with the > following high-end configuration: > > *Hardware* > > - Intel Core i7 3930k > - NVIDIA GeForce GTX 680 > - 32 GB RAM > > *Software* > > - Windows 7 Service Pack 1 64-bit > - Left 4 Dead 2 > - Ubuntu 12.04 32-bit > > We are using a 32-bit version of Linux temporarily and will run on 64-bit > Linux later. > Running Left 4 Dead 2 on Windows 7 with Direct3D drivers, we get 270.6 FPS > as a baseline. The data is generated from an internal test case. > > When we started with Linux, the initial version we got up and running was > at 6 FPS. This is typical of an initial successful port to a new platform. > Performance improvements fall into several categories: > > - Modifying our game to work better with the kernel > - Modifying our game to work better with OpenGL > - Optimizing the graphics driver > > An example of the first category would be changing our memory allocator to > use more appropriate Linux functions. This was achieved by implementing the > Source engine small block heap to work under Linux. The second category > would include reducing overhead in calling OpenGL, and extending our > renderer with new interfaces for better encapsulation of OpenGL and > Direct3D. > The third category is especially interesting because it involves working > with hardware manufacturers to identify issues in their drivers and, as a > result, improving the public driver which benefits all games. Identifying > driver stalls and adding multithreading support in the driver are two > examples of changes that were the result of this teamwork. > After this work, Left 4 Dead 2 is running at 315 FPS on Linux. That the > Linux version runs faster than the Windows version (270.6) seems a little > counter-intuitive, given the greater amount of time we have spent on the > Windows version. However, it does speak to the underlying efficiency of the > kernel and OpenGL. Interestingly, in the process of working with hardware > vendors we also sped up the OpenGL implementation on Windows. Left 4 Dead 2 > is now running at 303.4 FPS with that configuration. > OpenGL versus Direct3D on Windows 7 > > This experience lead to the question: why does an OpenGL version of our > game run faster than Direct3D on Windows 7? It appears that it’s not > related to multitasking overhead. We have been doing some fairly close > analysis and it comes down to a few additional microseconds overhead per > batch in Direct3D which does not affect OpenGL on Windows. Now that we know > the hardware is capable of more performance, we will go back and figure out > how to mitigate this effect under Direct3D. > Working with hardware vendors > > We’ve been working with NVIDIA, AMD, and Intel to improve graphic driver > performance on Linux. They have all been great to work with and have been > very committed to having engineers on-site working with our engineers, > carefully analyzing the data we see. We have had very rapid turnaround on > any bugs we find and it has been invaluable to have people who understand > the game, the renderer, the driver, and the hardware working alongside us > when attacking these performance issues. > This is a great example of the benefits that are the result of close > coordination between software and hardware developers and should provide > value to the Linux community at large. > _______________________________________________ > Open mailing list > [email protected] > http://lists.partito-pirata.it/cgi-bin/mailman/listinfo/open _______________________________________________ Open mailing list [email protected] http://lists.partito-pirata.it/cgi-bin/mailman/listinfo/open
