Fork and Join feature jdk7 number of threads
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I have been studying the new feature in JDK 7, namely Fork and Join. In the Javadoc it states that in a ForkJoinTask one can not do fork only in the context of a ForkJoinPool. But it does not mention if the fork() method call creates a new thread or not. The ForkJoinPool uses a work-stealing algorithm to balance the work between threads, but nowhere mentions how many threads are actually created. Can someone help me with this? I have a task which I should break up in a divide-et-impera manner but I am worried that ForkJoinPool creates too many threads and would decrease the performance of the execution because of the overhead of managing these threads.

Thanks!