Aleksey Shipilëv is a Principal Engineer with 14+ years of deep expertise in Java platform performance, JVM internals, GC, JIT, and low-level x86 micro-optimizations, currently optimizing JDK performance at AWS. He has driven performance work across Oracle, Red Hat and open-source projects, contributing to flagship OpenJDK tools such as JOL, JMH, Loom and the JDK itself, with hands-on fixes touching GC implementations (Shenandoah, ZGC), continuations, and perf tooling. He combines systems-level C/C++ and VM development with practical Java SE/EE tuning and a toolbox of scripting “glue” technologies for testing and automation. Aleksey also applies machine-learning techniques to performance testing and is known for improving benchmark reliability and measurement accuracy in industry-standard tooling. Based in Potsdam, Germany, his contributions reflect both research-caliber insight and pragmatic engineering that measurably speeds runtimes and reduces datacenter energy use.
13 years of coding experience
19 years of employment as a software developer
Master of Science (MS) Computer Science, Master of Science (MS) Computer Science at Krasnoyarsk Summer School
Computer Science, Computer Science at Station of Young Technicians
Master of Science Computer Science, Master of Science Computer Science at ITMO University
Contributions:149 reviews, 1542 commits, 165 PRs in 9 years 11 months
Contributions summary:Aleksey primarily focused on optimizing the JMH framework. They contributed to improving code quality and maintainability by refactoring code for better exception handling. The user made significant improvements related to the reliability and measurement accuracy by addressing issues around multithreading and the handling of operations per invocation and also improved the efficiency of the perfasm profiler.
Contributions:40 reviews, 209 commits, 74 PRs in 9 years 2 months
Contributions summary:Aleksey made significant contributions to the `openjdk/jol` repository, focusing on improvements to the library's functionality. Their work included implementing proper class information display for introspection, enhancing samples for JDK 6 compatibility, and addressing initialization order issues within the `VMSupport` class. They also contributed fixes for experimental JRockit VM support and improvements to various output formats. Furthermore, the user addressed security exceptions and improved the estimates and heap dump utility.
code-toolsjolopenjdkjavalayout-engine
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Aleksey Shipilëv - Principal Engineer at Amazon Web Services (AWS)