Delphi High Performance: Master the art of concurrency, parallel programming, and memory management to build fast Delphi apps. 2 Ed

Cover....1

Title Page....2

Copyright and Credits....2

Contributors....4

Table of Contents....6

Preface....12

Chapter 1: About Performance....20

Technical requirements....20

What is performance?....21

Different types of speed....21

Algorithm complexity....22

Big O and Delphi data structures....26

Data structures in practice....30

Mr. Smith’s first program....35

Looking at code through Big O eyes....38

Summary....41

Chapter 2: Profiling the Code....42

Technical requirements....42

Don’t guess, measure!....43

Profiling with TStopwatch....43

Profilers....50

Summary....65

Chapter .3: Fixing the Algorithm....66

Technical requirements....67

Writing responsive user interfaces....67

Updating a progress bar....68

Bulk updates....71

Virtual display....74

Caching....80

Memoization....81

Dynamic cache....83

Speeding up SlowCode....88

Summary....91

Chapter 4: Don’t Reinvent, Reuse....92

Technical requirements....93

Spring for Delphi....93

Enumerations, collections, and lists....94

IEnumerable....96

ICollection....105

IList....106

Other interfaces....109

TEnumerable....109

Stacks and queues....111

Trees....120

Red-black trees....123

Sets and dictionaries....131

ISet....132

IMultiSet....134

IDictionary....136

IBiDiDictionary....139

Summary....143

Chapter 5: Fine-Tuning the Code....144

Technical requirements....145

Delphi compiler settings....145

Code inlining control....146

Optimization....147

Record field alignment....148

Assertions....151

Overflow checking....151

Range checking....152

Extracting common expressions....153

The helpful CPU window....155

Behind the scenes....157

A plethora of types....158

Simple types....159

Strings....159

Arrays....162

Records....165

Classes....176

Interfaces....177

Optimizing method calls....178

Parameter passing....178

Method inlining....186

The magic of pointers....189

Going the assembler way....193

Returning to SlowCode....196

Summary....197

Chapter 6: Memory Management....198

Technical requirements....199

Optimizing strings and array allocations....199

Memory management functions....203

Dynamic record allocation....205

FastMM4 internals....210

Memory allocation in a parallel world....213

Replacing the default memory manager....216

Logging memory manager....217

FastMM4 with release stack....222

FastMM5....225

TBBMalloc....225

Comparing memory managers....227

There is no silver bullet....228

Fine-tuning SlowCode....230

Summary....232

Chapter 7: Getting Started with the Parallel World....234

Technical requirements....235

Processes and threads....235

Multithreading....235

Multitasking....236

When to parallelize code....237

The most common problems....237

Never access the UI from a background thread....238

Simultaneous reading and writing....241

Sharing a variable....243

Hidden behavior....247

Synchronization....249

Critical sections....250

Other locking mechanisms....256

A short note on coding style....262

Shared data with built-in locking....263

Interlocked operations....264

Object life cycle....268

Communication....271

Windows messages....272

Synchronize and Queue....276

Polling....277

Performance....279

Third-party libraries....280

Summary....281

Chapter 8: Working with Parallel Tools....284

Technical requirements....284

TThread....285

Automatic life cycle management....288

Advanced TThread....290

Setting up a communication channel....292

Sending messages from a thread....296

Using TCommThread....298

Implementing a timer....300

Synchronizing with multiple workers....304

WaitForMultipleObjects....306

Condition variables....310

Comparing both approaches....315

Summary....315

Chapter 9: Exploring Parallel Practices....318

Technical requirements....319

Tasks and patterns....319

Variable capturing....320

Tasks....322

Exceptions in tasks....324

Parallelizing a loop....327

Thread pooling....330

Async/Await....332

Join....335

Join/Await....337

Future....342

Parallel for....344

Pipelines....349

Web spider....350

The filter stage....356

The downloader stage....358

The parser stage....359

Summary....362

Chapter 10: More Parallel Patterns....364

Technical requirements....364

Using OmniThreadLibrary....365

Blocking collections....366

Using blocking collections with TThread-based threads....368

Async/Await....371

Join....372

Future....376

Parallel Task....377

Background Worker....381

Initial query....384

Pipeline....389

Creating the pipeline....391

Stages....393

Displaying the result and shutting down....397

Map....398

Timed Task....400

Summary....404

Chapter 11: Using External Libraries....406

Technical requirements....406

Linking with object files....407

Object file formats....409

Object file linking in practice....410

Using C++ libraries....415

Writing exported functions....418

Using a proxy DLL in Delphi....420

Summary....424

Chapter 12: Best Practices....426

About performance....427

Profiling the code....427

Fixing the algorithm....428

Don’t reinvent, reuse....429

Fine-tuning the code....430

Memory management....431

Getting started with the parallel world....432

Working with parallel tools....435

Exploring parallel practices....436

More parallel patterns....437

Using external libraries....438

Final words....439

Index....440

Other Books You May Enjoy....448

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.

What You Will Learn:

• Get to grips with algorithmic complexity and learn how to recognize it
• Use tools to determine program runtime behavior
• Speed up programs by doing less instead of more
• Discover the internal workings of Delphi data structures
• Gain an understanding of Delphi's memory manager
• Find out how to write low-level parallel programs with TThread
• Use parallel patterns from the PPL and OTL libraries to write fast code
• Include external code, written in C or C++, in Delphi programs

Who this book is for:

This book is for all Delphi programmers. Whether you're a beginner or an accomplished programmer, you will find something interesting. Even though the focus is on the latest Delphi release, the code uses only standard Delphi syntax without syntactic additions from the latest releases, and most of it should compile and run in any Delphi from XE7 onward. If you're using an older version of Delphi, don't despair! Most of the concepts in this book do not depend on a specific Delphi version and will be useful for everyone.