Synchronisation in .NET– Part 1: lock(), Dictionaries and Arrays

As part of our tuning efforts at Livedrive, I ran into a deceptively simple problem that beautifully illustrates some of the scale principles I have been teaching to the SQL Server community for years.

In this series of blog entries, I will use what appears to be a simple .NET class to explore how modern CPU architectures handle high speed synchronisation. In the first part of the series, I set the stage and explore the .NET lock() method of coordinating data.

Thread Synchronization in SQL Server

Any code optimized for highly concurrent workloads must worry about thread synchronization. SQL Server is no exception, because in a database system, synchronization is one of the core functionalities you rely on the engine to provide (the noSQL crowd may ponder that a bit). In this blog post, I will describe the synchronization primitives, like locks, latches and spinlocks, used by SQL Server to coordinate access to memory regions between threads.