How does managed code & one address space improve performance? I can see that system calls will get cheaper, but is that a performance bottleneck? Or are there other improvements?
Basically when you switch between processes you have to update this. In 64 bit and some 32 bit operating systems you don't need to update the TLB to make system calls, the kernel shares address space with whatever process is running.
With a single process running I don't think the overhead is anything to concern yourself with, but if you have a lot of processes running I think it can measurably affect performance.
As eggnet said, you avoid the overhead of context switches, but you also avoid the restrictions of interprocess communication. That is typically done with sockets and marshalling, which can be orders of magnitude slower and more difficult to program than simple function calls.
