Book Image

Delphi High Performance - Second Edition

By : Primož Gabrijelčič
5 (1)
Book Image

Delphi High Performance - Second Edition

5 (1)
By: Primož Gabrijelčič

Overview of this book

Performance matters! Users hate to use programs that are not responsive to interactions or run too slow to be useful. While becoming a programmer is simple enough, you require dedication and hard work to achieve an advanced level of programming proficiency where you know how to write fast code. This book begins by helping you explore algorithms and algorithmic complexity and continues by describing tools that can help you find slow parts of your code. Subsequent chapters will provide you with practical ideas about optimizing code by doing less work or doing it in a smarter way. The book also teaches you how to use optimized data structures from the Spring4D library, along with exploring data structures that are not part of the standard Delphi runtime library. The second part of the book talks about parallel programming. You’ll learn about the problems that only occur in multithreaded code and explore various approaches to fixing them effectively. The concluding chapters provide instructions on writing parallel code in different ways – by using basic threading support or focusing on advanced concepts such as tasks and parallel patterns. By the end of this book, you’ll have learned to look at your programs from a totally different perspective and will be equipped to effortlessly make your code faster than it is now.
Table of Contents (15 chapters)

Async/Await

The Async/Await program from the code folder for this chapter demonstrates the use of the Async/Await pattern in OTL. It is practically identical to the PPL version from the last chapter’s code. This is not surprising, given that I had implemented the PPL version of Async/Await, mimicking the OTL version. The biggest change in the code was replacing the System.Threading unit with OtlParallel. The following code fragment shows the method that runs the LongTask method in a background thread by using the OTL Async/Await:

procedure TfrmAsyncAwait.btnLongTaskAsyncClick(
  Sender: TObject);
begin
  Log(Format('Button click in thread %d',
    [TThread.Current.ThreadID]));
  (Sender as TButton).Enabled := false;
  Async(LongTask)
  .Await(
    procedure
    begin
      Log(Format('Await in thread %d',
  ...