Foreword

I have worked in the software industry for more than 15 years, the last four years as CIO of Sabre Holdings and the prior four as CTO of Travelocity. At Sabre, on top of our large online presence through Travelocity, we transact $70 billion in annual gross travel sales through our network and serve over 200 airline customers worldwide. On a given day, we will process over 700 million transactions and handle 32,000 transactions per second at peak. Working with massive streams of data is what we do, and finding better ways to work with this data and improve throughput is my role as CIO.

Troy is our VP over Architecture at Travelocity, where I have the pleasure of watching his influence on a daily basis. His perspective on current and future problems and depth of detail are observed in his architectural decisions, and you will find this capability very evident in this book on the subject of LINQ and PLINQ.

Developer productivity is a critical aspect for every IT solution-based business, and Troy emphasizes this in every chapter of his book. Languages and language features are a means to an end, and language features like LINQ offer key advances in developer productivity. By simplifying all types of data manipulation by adding SQL-style querying within the core .NET development languages, developers can focus on solving business problems rather than learning a new query language for every data source type. Beyond developer productivity, the evolution in technology from individual processor speed improvements to multi-core processors opened up a big hole in run-time productivity as much of today’s software lacks investment in parallelism required to better utilize these new processors. Microsoft’s investment in Parallel LINQ addresses this hole, enabling much higher utilization of today’s hardware platforms.

Open-standards and open-frameworks are essential in the software industry. I’m pleased to see that Microsoft has approached C# and LINQ in an open and inclusive way, by handing C# over as an ECMA/ISO standard, allowing everyone to develop new LINQ data-sources and to extend the LINQ query language operators to suit their needs. This approach showcases the traits of many successful open-source initiatives and demonstrates the competitive advantages openness offers.

Decreasing the ramp-up speed for developers to write and exploit the virtues of many-core processors is extremely important in today’s world and will have a very big impact in technology companies that operate at the scale of Sabre. Exposing common concurrent patterns at a language level offers the best way to allow current applications to scale safely and efficiently as core-count increases. While it was always possible for a small percentage of developers to reliably code concurrency through OpenMP or hand-rolled multi-threading frameworks, parallel LINQ allows developers to take advantage of many-core scalability with far fewer concerns (thread synchronization, data segmentation, merging results, for example). This approach will allow companies to scale this capability across a much higher percentage of developers without losing focus on quality. So roll up your sleeves and enjoy the read!

—Barry Vandevier
Chief Information Officer, Sabre Holdings