Workshop: Profiling JVM Applications in Production
Profiling JVM applications it not very easy in the first place. Many profilers, such as JVisualVM and jstack, will simply lie to your face about which call stacks are hottest and where your bottlenecks lie. Profiling in production environments has even more challenges, because you have to carefully manage overhead, account for other processes running on the system, and choose non-invasive tools that don't require an application restart. This is the workshop for you -- we will learn, understand, and experiment first-hand with JVM profiling tools designed for production use.
We will build a simple checklist for verifying JVM application performance, and finding the area to focus on in a closer investigation. Then, we will experiment with two approaches for CPU profiling on Linux: the perf multi-tool, combined with perf-map-agent, and the async-profiler project, an innovative tool that brings perf together with traditional JVM profiling techniques. We will visualize stack traces using flame graphs, and understand where the CPU bottlenecks lie, through a series of hands-on labs. In the second half of this workshop, we will talk about more complicated scenarios: diagnosing errors when opening files, tracing database queries, monitoring system I/O load, understanding the reasons for excessive garbage collection, figuring out why threads are blocked off-CPU, and more.
Outline:
- Linux and JVM performance information sources: tracepoints, {k,u}probes, USDT, JMX, JVMTI, Java SA, JFR, GC/JIT logs
- Linux JVM performance checklist: top, sar, free, iostat, pidstat, vmstat, jstack, jstat (based on hsperfdata), jcmd, jattach
- Linux perf, CPU sampling, getting stack reports, problem with symbols
- Generating perf maps with perf-map-agent, inline frames, source info
- Visualizing JVM profiles with flame graphs
- JVMTI profiling with an agent & jattach: GetAllStackTraces, exceptions, class loads, monitor contention [link] etc.
- Full-stack JVM profiling with async-profiler, how it works, pros and cons
- Introduction to BPF
- BPF scenarios and the BCC toolkit, Java-specific tools, JVM USDT probes, -XX:+ExtendedDTraceProbes
- Dedicated BCC tools: fileslower, opensnoop, gethostlatency, runqlat, cpudist
- General-purpose BCC tools: trace, argdist, funccount, stackcount, funclatency
- Heap allocation profiling (based on TLAB sampling) with async-profiler vs. funccount/stackcount vs. grav
Other Workshops:
Tracks
Monday, 5 March
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Leading Edge Backend Languages
Code the future! How cutting-edge programming languages and their more-established forerunners can help solve today and tomorrow’s server-side technical problems.
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Security: Red XOR Blue Team
Security from the defender's AND the attacker's point of view
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Microservices/ Serverless: Patterns and Practices
Stories of success and failure building modern service and function-based applications, including event sourcing, reactive, decomposition, & more.
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Stream Processing in the Modern Age
Compelling applications of stream processing & recent advances in the field
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DevEx: The Next Evolution of DevOps
Removing friction from the developer experience.
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Modern CS in the Real World
Applied trends in Computer Science that are likely to affect Software Engineers today.
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Speaker AMAs (Ask Me Anything)
Tuesday, 6 March
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Next Gen Banking: It’s not all Blockchains and ICOs
Great technologies like Blockchain, smartphones and biometrics must not be limited to just faster banking, but better banking.
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Observability: Logging, Alerting and Tracing
Observability in modern large distributed computer systems
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Building Great Engineering Cultures & Organizations
Stories of cultural change in organizations
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Architectures You've Always Wondered About
Topics like next-gen architecture mixed with applied use cases found in today's large-scale systems, self-driving cars, network routing, scale, robotics, cloud deployments, and more.
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The Practice & Frontiers of AI
Learn about machine learning in practice and on the horizon
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JavaScript and Beyond: The Future of the Frontend
Exploring the great frontend frameworks that make JavaScript so popular and theg JavaScript-based languages revolutionising frontend development.
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Speaker AMAs (Ask Me Anything)
Wednesday, 7 March
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Distributed Stateful Systems
Architecting and leveraging NoSQL revisitied
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Operating Systems: LinuxKit, Unikernels, & Beyond
Applied, practical, & real-world deep-dive into industry adoption of OS, containers and virtualisation, including Linux on Windows, LinuxKit, and Unikernels
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Architecting for Failure
If you're not architecting for failure you're heading for failure
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Evolving Java and the JVM: Mobile, Micro and Modular
Although the Java language is holding strong as a developer favourite, new languages and paradigms are being embraced on JVM.
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Tech Ethics in Action
Learning from the experiences of real-world companies driving technology decisions from ethics as much as technology.
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Bare Knuckle Performance
Killing latency and getting the most out of your hardware
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Speaker AMAs (Ask Me Anything)