Douglas Hawkins

How a Compiler Works -- and Why It Matters to You

8:30 AM MDT

To write efficient SQL, you need to understand SQL execution plans. And to write efficient Java, you need to understand the JVM's execution plan.

In this talk, you'll learn how the JVM's Just-in-Time compiler analyzes Java code. Then we'll go through an example in detail to see how code optimization really works.

How (Not) To Measure and Profile Java Performance

10:30 AM MDT

Today, we all benefit from the sophistication of modern compilers and hardware, but that extra complexity can also make it difficult to reason about performance.

In this talk, we'll examine some surprising performance cases and learn how to
use profiling and benchmarking tools to better understand our modern execution environments.

JVM Mechanics

1:30 PM MDT

HotSpot promises to do wonders for us by Just-in-Time (JIT) compiling the “right” code for us, but how does it makes those decisions? And, perhaps more importantly, what happens when it's wrong?

In this talk, you'll learn through real code examples just how the JVM decides to compile your code, deoptimize your code, and stop-the-world for a GC.

Java Optimizations That Matter (and Some That Don't)

3:15 PM MDT

Early releases of Java performed poorly, but those issues largely disappeared long ago with the introduction of HotSpot. However, much of the performance advice for Java persists through hearsay from those early days.

In this talk, we'll forget the hearsay and take an objective look using benchmarking and profiling tools to find out which optimizations matter today and just as importantly those that don't.

Concurrency Concepts in Java

5:00 PM MDT

Unlike earlier languages, Java had a well-defined threading and memory model from the beginning. And over the years, Java gained new packages to help solve concurrency problems.

Despite this, Java concurrency is sometimes subtle and fraught with peril.

In this talk, you'll learn these subtleties. And finally, you'll learn how to handle concurrency by exploring the concepts behind java.util.concurrent and other concurrency libraries.

Understanding Garbage Collection

3:15 PM MDT

Most of us don't want to go back to the days of malloc and free, but the garbage collector isn't always our friend.

In this presentation, you'll learn about the different garbage collection strategies used in JVMs, how to monitor garbage collection, analyze memory dumps, and why you might want to use one collection strategy instead of another.

Architecting with Garbage Collection in Mind

5:00 PM MDT

HotSpot provides a variety of garbage collectors with a variety of strengths and weaknesses. To get the most out of our applications, we need to pick the right garbage collector and design to take advantage of its strengths and avoid its
weaknesses.

In this presentation, you'll learn about criteria for picking a garbage collector, how to measure GC performance, and how to write code that works with rather than against the GC.