Gabrijelčič - Delphi high performance: build fast Delphi applications using concurrency, parallel programming and memory management

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First published: February 2018

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ISBN 978-1-78862-545-6

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Primo Gabrijeli started coding in Pascal on 8-bit micros in the 1980s and he never looked back. In the last 20 years, he was mostly programming high-availability server applications used in the broadcasting industry. A result of this focus was the open sourced parallel programming library for DelphiOmniThreadLibrary. He's also an avid writer and has written several hundred articles, and he is a frequent speaker at Delphi conferences where he likes to talk about complicated topics, ranging from memory management to creating custom compilers.

Stefan Glienke, since his very first steps with Turbo Pascal in school, was passionate about programming. In his spare time, he worked at a software company using Visual Basic and started learning C++ and Delphi and decided to start an apprenticeship as a software developer after graduation.

Over the years, he developed an interest in software architecture and began helping fellow developers improve their skills, participating in several open source projects, such as Spring4D. He is also the author of TestInsight.

Stefan has worked as reviewer on the books Coding in Delphi and Dependency Injection in Delphi.

Bruce McGee is the founder of Glooscap Software, a software development and consulting company in Toronto, Ontario. He is also a long-time Delphi user, which he continues to work with every day.

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Performance matters!

I started programming on 8-bit micros, and boy, was that an interesting time! Memory was typically not a problem as we didn't write big programs, but they certainly weren't running fast, especially if you run them with a built-in BASIC interpreter. It is not surprising that I quickly learned assembler and spent lots of early years shifting bits and registers around. So did almost everybody else who wanted to release a commercial application written for one of those computers. There were, more or less, no games and applications written in BASIC simply because they would run too slow and nobody would use them.

Time has changed; computers are now fastincredibly fast! If you don't believe me, check the code examples for this book. A lot of times, I had to write loops that spin over many million iterations so that the result of changing the code would be noticed at all. The raw speed of processors has also changed the software development world. Low-level languages such as assembler and C mostly gave way to more abstract approachesC#, C++, Delphi, F#, Java, Python, Ruby, JavaScript, Go, and so on. The choice is yours. Almost anything you write in these languages runs fast or at least fast enough.

Computers are so fast that we sometimes forget the basic ruleperformance matters. Customers like programs that operate so fast that they don't have to think about it. If they have to wait 10 seconds for a form to appear after clicking on a button, they won't be very happy. They'll probably still use the software, though, provided that it works for them and doesn't crash. On the other hand, if you write a data processing application that needs 26 hours for a job that executes daily, you'll certainly lose them.