GDC09: Why CPUs are important to game developers

During his yesterday's tech session Leigh Davies shared several useful tips with the audience how game developers can benefit from current and future micro processors.

As I have blogged already, especially Intel Core i7 architecture provides a lot of powerful features: high bandwidth, improved SIMD instructions, Simultaneous Multi-Threading (formerly known as Hyper-Threading) and much more.

But first of all Leigh talked about Intel's tic-toc model: Since 2005 Intel is announcing every odd year a new processor generation and a die-shrink in even years as manufacturing processes are being improved constantly. Currently there is a technology shift from 45 to 32 nanometers.

During his session Leigh quoted the famous word "The free lunch is over". This statement is going back to an Harsh Sutter article where he is talking about the fact that since 2005 microprocessor's clock rates don't increase anymore significantly, but the number of processor cores do. As a result software developers have to optimize existing or new applications more and more for multi-core platforms.

So, Leigh first tip sounded like this: “Take a look at new hardware platforms as early as possible!” Only then developers can get the best out of existing architectures to optimize their applications more efficiently. So they have to take care of the available number of processor cores for example, and thus the maximum number of threads per CPU core. But also the enhancements of the SIMD instruction set SSE4.2 which is currently implemented in Core i7 micro architecture is really useful to software developers. So Leigh's second tip goes like this: “Your customers have SSE, so use it!”.

Finally Leigh's third tip had to do with the available number of processor cores per PC: “As it's quite dangerous to 'guess" the CPU cores in a single machine, go and compute it!” And there are dedicated code examples on intel.com referring to this issue.

Right after his tech session Leigh Davies took some time to answer our questions. So please click the picture to start the video clip.

For more complete information about compiler optimizations, see our Optimization Notice.