private void runAll(Thread[] threads) {
        for (Thread t : threads) {
            t.start();
        }
        for (Thread t : threads) {
            try {
                t.join();
            } catch (InterruptedException e) {
                // nop
            }
        }
    }
Smoke test for multi producer data structure.

<p>
TODO sorely needs nastier cases
</p>

@author <a href="mailto:steinar@yahoo-inc.com">Steinar Knutsen</a>
vespajlib/src/test/java/com/yahoo/concurrent/ThreadLocalDirectoryTestCase.java