Author: manik.surtani(a)jboss.com Date: 2008-10-13 12:59:48 -0400 (Mon, 13 Oct 2008) New Revision: 6917 Added: core/branches/flat/src/test/java/org/jboss/starobrno/lock/ core/branches/flat/src/test/java/org/jboss/starobrno/lock/LockContainerHashingTest.java Log: hash distribution test Added: core/branches/flat/src/test/java/org/jboss/starobrno/lock/LockContainerHashingTest.java =================================================================== --- core/branches/flat/src/test/java/org/jboss/starobrno/lock/LockContainerHashingTest.java (rev 0) +++ core/branches/flat/src/test/java/org/jboss/starobrno/lock/LockContainerHashingTest.java 2008-10-13 16:59:48 UTC (rev 6917) @@ -0,0 +1,92 @@ +/* + * JBoss, Home of Professional Open Source + * Copyright 2008, Red Hat Middleware LLC, and individual contributors + * by the @authors tag. See the copyright.txt in the distribution for a + * full listing of individual contributors. + * + * This is free software; you can redistribute it and/or modify it + * under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * This software is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this software; if not, write to the Free + * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA, or see the FSF site: http://www.fsf.org. + */ +package org.jboss.starobrno.lock; + +import org.jboss.cache.util.concurrent.locks.LockContainer; +import org.jboss.cache.util.concurrent.locks.ReentrantLockContainer; +import org.testng.annotations.BeforeMethod; +import org.testng.annotations.Test; + +import java.util.ArrayList; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Random; +import java.util.concurrent.locks.Lock; + +@Test(groups = "unit") +public class LockContainerHashingTest +{ + private LockContainer<String> stripedLock; + + @BeforeMethod(alwaysRun = true) + public void setUp() + { + stripedLock = new ReentrantLockContainer<String>(500); + } + + public void testHashingDistribution() + { + // ensure even bucket distribution of lock stripes + List<String> keys = createRandomKeys(1000); + + Map<Lock, Integer> distribution = new HashMap<Lock, Integer>(); + + for (String s : keys) + { + Lock lock = stripedLock.getLock(s); + if (distribution.containsKey(lock)) + { + int count = distribution.get(lock) + 1; + distribution.put(lock, count); + } + else + { + distribution.put(lock, 1); + } + } + + System.out.println(distribution); + + // cannot be larger than the number of locks + System.out.println("dist size: " + distribution.size()); + System.out.println("num shared locks: " + stripedLock.getSize()); + assert distribution.size() <= stripedLock.getSize(); + // assume at least a 2/3rd spread + assert distribution.size() * 1.5 >= stripedLock.getSize(); + } + + private List<String> createRandomKeys(int number) + { + + List<String> f = new ArrayList<String>(number); + Random r = new Random(); + int i = number; + while (f.size() < number) + { + String s = i + "baseKey" + (10000 + i++); + f.add(s); + } + + return f; + } +}