multiprocessor problem!!

I am trying to do two multiprocessor systems implenting two purpose individually:

1) use mutex to access a shared resource

2) use mailbox to communicate between processors

I did 1) following the Altera document "Creating Multiprocessor NIOSII tutorial" and using the hello_world_multi.c as the program(which I think available on the net). The problem is: When I run it, I cann't get the 2 processors' outputs in one Terminal in NIOS IDE, only CPU1 continously prints out , no output of CPU2. But when I use DEBUG and control the excution of the two processors manually, then everything is ok as the tutorial shows. What's the problem?

In 2) I made cpu1 post a mail, and I hope cpu2 can receive it by blocking(using pending method). But when I run the project, the cpu2 just blocks. If I use the DEBUG and control the excution, everything is OK, what's the problem?

Why during RUN and DEBUG the result were so different?

Thanks.