Woa... Way not enough information. What OS is the code running on? I assume we're talkin itheads? Are you using join() or detach()? Are the worker threads doing system calls? Writing to disk? What do you mean by interupted?

In general the worker threads have to finish, ie. exit normally, before join() and detach() can clean up.

From perlthrtut

"Similarly, mixing signals and threads should not be attempted."