Last week I attended a review session of the new JSR166 StampedLock run by Heinz Kabutz at the excellent JCrete unconference. StampedLock is an attempt to address the contention issues that arise in a system when multiple readers concurrently access shared state. StampedLock is designed to perform better than ReentrantReadWriteLock by taking an optimistic read approach. While attending the session
![Lock-Based vs Lock-Free Concurrent Algorithms](https://cdn-ak-scissors.b.st-hatena.com/image/square/84bd1df10d7a3768373647ce5d7ad81ce6d7f46c/height=288;version=1;width=512/https%3A%2F%2Fblogger.googleusercontent.com%2Fimg%2Fb%2FR29vZ2xl%2FAVvXsEgbYCB5dGeAADODQ73ElIkfi1ecNVo8KQncGgQvcPRKqTO1tLCGDrWUjFooCo3YH1_3ndX06ovaFUGZkwZxyulP3xvrFVE6LTs1T3mTAuF85Mo_Azedrs48Wybi7FinTpzScOgEDc4T6uU%2Fw1200-h630-p-k-no-nu%2F1-reader-1-writer.png)