Today I learned about a very interesting (undocumented) compiler flag in Visual Studio 2005. With the simple addition of
/MP to the C++ Additional Options for your project, the compiler will take advantage of multiple processors. Obviously you need a multi-processor machine for this to work.
So how much difference are we talking? The project I’m currently working on took 5:00 to build on my FX-70 machine at work. Adding this flag dropped the number to 1:53. In compiling our full solution (7 projects), setting the number of parallel project builds to 2 and adding the /MP flag took 14 minutes 20 seconds (an overall improvement of 3 minutes from having 3 project builds an no /MP flag). The IDE remained responsive during the build (the first thing I had to test).
Definitely made my day better!