I am experimenting to write a little search engine in perl. It uses mysql tables as "stacks" for the URLs it has to visit on the curent level, for the links it found to the next level and for storing CRCs of visited URLs. I do test runs with a version running 10 parallel threads.

After some minutes it suddently terminates with this strange message:
Alarm clock

But I didn't request such a feature! What can I do or did I do wrong? What kind of things cause this error and program termination? If I knew that, it would make fixing the program a lot easier. Thanks for any help!

I used these perl modules: DBI, threads, threads::shared, all newest versions from portage.

If you would like to look at the code:
http://pastebin.com/392151

In reply to "Alarm clock" termination by nyk

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