Do spurious wakeups in Java actually happen?

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The Wikipedia article on spurious wakeups has this tidbit:

The pthread_cond_wait() function in Linux is implemented using the futex system call. Each blocking system call on Linux returns abruptly with EINTR when the process receives a signal. … pthread_cond_wait() can’t restart the waiting because it may miss a real wakeup in the little time it was outside the futex system call. This race condition can only be avoided by the caller checking for an invariant. A POSIX signal will therefore generate a spurious wakeup.

Summary: If a Linux process is signaled its waiting threads will each enjoy a nice, hot spurious wakeup.

I buy it. That’s an easier pill to swallow than the typically vague “it’s for performance” reason often given.

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