Why doesn Vista handle concurrency?
Vista strives to provide the minimal building block for transactions. Many applications are single-threaded and hence need no concurrency control. Applications that do need concurrency control can layer a locking mechanism on top of Vista. Vista’s fast transactions minimize lock hold times and hence make this job easier. We just don’t want to penalize single-threaded applications (that don’t need to lock data). • Why isn’t group commit good enough? Group commit is a technique for improving throughput. Vista improves latency, which is a more general way of improving throughput. Group commit works only if there are concurrent, independent transactions. Vista works even for applications with serial or dependent transactions. Finally, Vista is 100 times faster than a system with group commit. • Does Vista work for working sets larger than main memory? Vista operates correctly with data sets that are larger than main memory. As with any transaction system or database, Vista performs poorly
