What are the 1> and 2> in the Visual Studio build window? The number some time goes higher. Processes? Threads? Nesting? I never seen them before and they started showing up on my new machine which now is dual core.
They are thread numbers. On multiprocessor machines, VS distributes the build among several threads, and numbers each one. When a thread finishes it can be killed off and a new one started, which is why you see increasing numbers in there.
If you find it annoying that the output from these threads is all mingled together, use the "Build order" option in the "Show output from" dropdown to show each thread's output in one piece.
It's parallel project builds in VS. >1 all the output from one project and >2 is the output from another project being build.
The option is controled in Tools / Options / Projects and Solutions / Build and Run / Maximum number of parallel project builds. The default on install is normally the number of CPU's are in your system.
If your solution has more than 1 project then up to x number of projects are build in parallel. The projects built in parallel also depends on project dependances as well i.e. dependant projects will not build in parallel.