# JIT Published articles for JIT. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Module Tracking in Swift Debug Info DevFeed: [Module Tracking in Swift Debug Info]() Original publisher: [Read original article]() Author: Adrian Prantl Published: 2026-09-11T15:30:00Z Content type: tutorial Language: en Sources: [Swift.org]() Topics: [debugging](), [debug](), [toolchain](), [C++]() Tags: [cmake](), [debug](), [debugger](), [debugging](), [jit](), [swift]() ### AI overview Swift 6.3 and the upcoming Swift 6.4 improve how explicitly built Swift modules are referenced in debug information. The article explains how this helps LLDB locate modules for expression evaluation, improving debugging reliability and reducing build products, while noting that custom build systems may need adjustments. ### Source excerpt When your Swift program hits a breakpoint and stops so you can inspect it, the debugger's expression evaluator has to find the exact Swift module your code was built from. Until now, that lookup wasn't always precise. The upcoming Swift 6.4 release will include changes, begun in Swift 6.3, that address this by updating how the Swift compiler references explicitly-built Swift modules in debug info. The majority of developers will automatically benefit from faster, more reliable debugging and smaller build products, without any modifications to their SwiftPM or Xcode projects. For developers who maintain their own build systems using, for example, Bazel, Buck, or CMake, some adjustments may be necessary to take advantage of these changes. This article explains how the debugger uses Swift modules. Next, it describes how Swift 6.3 changes the way modules are tracked in debug info to solve several problems with the previous representation. Finally, it shows how to adjust build systems to take advantage of the new representation and eliminate some build steps that are no longer necessary. Swift modules and expression evaluation LLDB's standout feature is its powerful expression evaluator. Because LLDB embeds the Clang and Swift compilers, it can JIT-compile any valid source code and run it in the context of your application while stopped at a breakpoint. This includes not just calling code in your application, but also defining new data types, functions, and closures. Debugging features that are usually reserved for interpreted or JIT-compiled languages like JavaScript become available to ahead-of-time-compiled languages like C++ and, of course, Swift! In order to JIT-compile user expressions that make use of data types defined in the debugged program, LLDB's embedded Swift compiler needs to import the Swift modules defining those types. In a world before explicitly-built modules, LLDB would find the base name of the main module at the current breakpoint in the debug info ## Postgres 19: How Our Advice Has Changed Since We Wrote It DevFeed: [Postgres 19: How Our Advice Has Changed Since We Wrote It]() Original publisher: [Read original article]() Author: Christopher Winslett Published: 2026-08-18T19:00:00Z Content type: article Language: en Sources: [CrunchyData Blog]() Topics: [data](), [JIT](), [Latency](), [Temporal data](), [Linux]() Tags: [advice](), [async](), [benchmarks](), [index](), [jit](), [latency](), [linux](), [maintenance](), [parallel](), [partitioning](), [postgres](), [postgres-19](), [production-postgres](), [release](), [storage](), [upgrade]() ### AI overview This article revisits earlier Crunchy Data guidance on loading, storage, indexes, and partitioning for the upcoming Postgres 19 release. It explains which changes in Postgres 18 and 19 affect that advice, including asynchronous I/O, parallel maintenance, BRIN and skip-scan behavior, partition operations, and JIT being disabled by default. The details are based on current betas and may change before general availability. ### Source excerpt Revisiting Crunchy posts on COPY, TOAST, BRIN, covering indexes, and partitioning: what we said then, which Postgres versions changed the story, and what we recommend on Postgres 19. ## How we improved APM Java startup by encoding a prefix trie as a JVM constant DevFeed: [How we improved APM Java startup by encoding a prefix trie as a JVM constant]() Original publisher: [Read original article]() Author: Stuart McCulloch Published: 2026-08-11T00:00:00Z Content type: article Language: en Sources: [Datadog | The Monitor blog]() Topics: [telemetry]() Tags: [apm](), [instrumentation](), [java](), [jit](), [observability](), [open-source](), [optimization](), [performance](), [startup]() ### AI overview Datadog explains how it reduced Java APM startup overhead by encoding multiple class-name prefix matches as a JVM string constant. The approach improves class matching while preserving targeted instrumentation for observability. ### Source excerpt Learn how the Datadog APM team improved Java startup performance by encoding a prefix trie as a JVM string constant. ## Python 3.15.0 candidate 1 is here! DevFeed: [Python 3.15.0 candidate 1 is here!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-08-04T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [Maintainers](), [Compiler](), [JIT](), [Linux](), [macOS](), [Windows]() Tags: [documentation](), [jit](), [linux](), [macos](), [maintainers](), [performance](), [python](), [release](), [releases](), [windows]() ### AI overview Python 3.15.0rc1 is the first release candidate in the Python 3.15 series. The article asks third-party maintainers to test the release, publish compatible wheels, report issues, and complete documentation before the final release. ### Source excerpt Get those wheels rolling! ## ModelExpress: Distributing Model Artifacts at the Speed of Light DevFeed: [ModelExpress: Distributing Model Artifacts at the Speed of Light]() Original publisher: [Read original article]() Author: Elizabeth Goodman Published: 2026-07-24T16:45:00Z Content type: article Language: en Sources: [NVIDIA Developer](), [NVIDIA Technical Blog]() Topics: [model-deployment](), [GPU](), [P2P](), [Amazon S3](), [autoscaling](), [Caching](), [cloud-infrastructure]() Tags: [agentic-ai-generative-ai](), [ai-foundation-models](), [ai-inference](), [autoscaling](), [data-center-cloud](), [developer-tools-techniques](), [dynamo-triton](), [featured](), [gpu](), [inference](), [inference-performance](), [jit](), [llms](), [local](), [model](), [s3](), [scale](), [speed](), [streaming]() ### AI overview NVIDIA ModelExpress (MX) reduces model-serving startup time by locating compatible model weights at the fastest available source. It prioritizes direct GPU-to-GPU transfer over P2P RDMA from an existing serving replica, while using object or local storage for initial bootstrapping and fallback. The article also describes reusing JIT kernel caches and distributing reinforcement-learning weight updates. ### Source excerpt Every byte moved has a cost. As model checkpoints grow to hundreds of gigabytes or even a terabyte, that cost adds up quickly. To make things even worse, moving... ## Engineering quality compounds DevFeed: [Engineering quality compounds]() Original publisher: [Read original article]() Author: Mike Shaver, Avery Pennarun Published: 2026-07-21T13:00:00Z Content type: news Language: en Sources: [Blog on Tailscale]() Topics: [engineering-leadership](), [Architecture & Design](), [Firefox](), [systems](), [JIT](), [Linux](), [JavaScript](), [Security](), [Shopify]() Tags: [developer](), [engineering](), [engineering-leadership](), [firefox](), [javascript](), [jit](), [linux](), [news](), [platform](), [security](), [shopify](), [systems]() ### AI overview Mike Shaver joins Tailscale as VP of Engineering, bringing experience in platform engineering, Firefox, Facebook's mobile transition, security products, systems programming, and edge infrastructure. The article frames his role around scaling engineering quality while keeping Tailscale's product reliable, useful, and understandable. ### Source excerpt Mike Shaver joins Tailscale to scale engineering quality. ## Python 3.15.0 beta 4 is here! DevFeed: [Python 3.15.0 beta 4 is here!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-07-18T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [Compiler](), [observability]() Tags: [jit](), [maintainers](), [observability](), [performance](), [python](), [release](), [releases](), [testing]() ### AI overview Python 3.15.0b4 is the final planned beta release, bringing bug fixes, build improvements, documentation changes, new language and packaging features, improved observability, and a significantly upgraded JIT compiler. The article asks maintainers to test the beta and report issues before the release candidate phase. ### Source excerpt The final 3.15 beta is out! ## Eliminating Java cold starts with AWS Lambda Managed Instances DevFeed: [Eliminating Java cold starts with AWS Lambda Managed Instances]() Original publisher: [Read original article]() Author: Jay Colodner Published: 2026-07-13T20:23:19Z Content type: article Language: en Sources: [AWS Compute Blog]() Topics: [AWS Lambda](), [benchmarking](), [Amazon Web Services](), [Amazon EC2](), [Spring Boot 4](), [cpu](), [SDKs]() Tags: [aws](), [aws-lambda](), [benchmark](), [benchmarking](), [benchmarks](), [comparison](), [cpu](), [deployment](), [java](), [jit](), [latency](), [on-call](), [performance](), [spring-boot-4](), [uncategorized]() ### AI overview This article benchmarks four Java deployment modes for AWS Lambda: Standard Lambda, SnapStart, GraalVM Native Image, and Lambda Managed Instances. Using identical Spring Boot applications across CPU-bound, I/O-plus-computation, and I/O-bound workloads, it reports that Managed Instances preserve JVM state and enable JIT optimization, improving median and tail latency while reducing cold-start spikes. ### Source excerpt A single cold start can push your Java Lambda function's response time from milliseconds to seconds, enough to violate your p99 SLA, timeout a downstream service, and page your on-call. The Java Virtual Machine (JVM) performs best in long-running processes. Its Just-In-Time (JIT) compiler progressively optimizes code over thousands of invocations. Standard serverless execution environments [...] ## Python 3.15.0 beta 3 is here! DevFeed: [Python 3.15.0 beta 3 is here!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-06-23T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [Compiler](), [observability]() Tags: [bug](), [jit](), [linux](), [macos](), [maintainers](), [observability](), [python](), [releases](), [testing](), [windows]() ### AI overview Python 3.15.0 beta 3 is the third of four planned beta releases, with bug fixes, build improvements, documentation changes, and contributions from 86 contributors. The preview introduces or advances features including lazy imports, profiling tools, frame pointers for observability, UTF-8 by default, package startup configuration, and an upgraded JIT compiler. ### Source excerpt The penultimate 3.15 beta is out! ## 【eBPF 内核实现深度拆解】从验证器到 JIT，从 BTF 到调度器 DevFeed: [【eBPF 内核实现深度拆解】从验证器到 JIT，从 BTF 到调度器]() Original publisher: [Read original article]() Author: Liao Tonglang Published: 2026-06-12T00:00:00Z Content type: article Language: zh Sources: [土法炼钢 - 系统与基础设施]() Topics: [eBPF](), [Linux](), [JIT](), [Benchmark](), [clang](), [hash](), [benchmarking](), [RISC-V](), [ast-matchers]() Tags: [arm](), [array](), [benchmark](), [bpf-jit](), [bpf-maps](), [bpf-verifier](), [btf](), [clang](), [co-re](), [cpu](), [ebpf](), [fentry](), [hash](), [jit](), [kernel](), [libbpf](), [linux](), [linux-kernel](), [precision](), [risc-v](), [sched-ext](), [trampoline](), [x86](), [xdp]() ### AI overview This Chinese-language series systematically explains eBPF's Linux kernel implementation, covering the BPF instruction set and registers, verifier algorithms, JIT compilation, map data structures and concurrency, helper type checking, BTF and CO-RE relocation, libbpf loading, trampolines, and sched_ext interfaces. It is aimed at engineers who want to understand eBPF kernel source code and build production BPF programs. ### Source excerpt eBPF 内核虚拟机内部实现系统讲解：BPF 指令集与寄存器机器、验证器的抽象解释与状态裁剪、JIT 编译器后端、Map 各类型的并发与内存模型、helper 函数注册与类型检查、BTF 格式规范与 CO-RE 重定位引擎、libbpf 加载器工程、fentry/fexit 蹦床机制、sched_ext 调度器内核接口。面向想读懂 eBPF 内核源码、写生产级 BPF 程序的系统工程师。 ## Python 3.15.0 beta 2 is here! DevFeed: [Python 3.15.0 beta 2 is here!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-06-02T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [JIT](), [observability](), [Compiler]() Tags: [jit](), [maintainers](), [observability](), [performance](), [python](), [release](), [releases](), [testing]() ### AI overview Python 3.15.0b2 is the second of four planned beta releases. The preview includes new language and type-system features, profiling and observability improvements, a significantly upgraded JIT compiler, improved error messages, and updated Windows binaries. The article encourages maintainers to test the beta and report issues, while recommending that production releases wait until the first release candidate. ### Source excerpt The antepenultimate 3.15 beta is out! ## Python 3.14.5 is out! DevFeed: [Python 3.14.5 is out!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-05-10T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python 3.14](), [Python](), [Compression](), [JIT](), [Processes](), [Android](), [macOS](), [Windows]() Tags: [android](), [compression](), [features](), [jit](), [macos](), [memory](), [processes](), [python](), [python-3-14](), [release](), [releases](), [windows]() ### AI overview Python 3.14.5 is the fifth maintenance release in the Python 3.14 series, with approximately 154 bug fixes, build improvements, and documentation changes. It reverts the incremental garbage collector to the generational collector used in Python 3.13 because of reported production memory pressure. The release also updates Tcl/Tk on macOS and documents major Python 3.14 features, including free-threaded support, deferred annotation evaluation, template string literals, multiple interpreters, Zstandard support, debugging interfaces, an experimental JIT, and Android binaries. ### Source excerpt A special release with a new (old) garbage collector. ## Python 3.15.0 beta 1 is here! DevFeed: [Python 3.15.0 beta 1 is here!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-05-07T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [Linux](), [observability](), [macOS](), [Windows](), [configuration]() Tags: [jit](), [maintainers](), [observability](), [performance](), [python](), [release](), [releases](), [testing]() ### AI overview Python 3.15.0 beta 1 is the first beta release and marks the feature freeze. The article highlights new language and type-system features, profiling and observability improvements, UTF-8 as the default encoding, C API and stable ABI changes, JIT performance gains, and updated Windows binaries. It also asks maintainers to test the beta and report issues, while recommending that production releases wait for the first release candidate. ### Source excerpt The propreantepenultimate 3.15 beta is out! ## Python 3.15.0a8, 3.14.4 and 3.13.13 are out! DevFeed: [Python 3.15.0a8, 3.14.4 and 3.13.13 are out!]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-04-07T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [releases]() Tags: [api](), [bugs](), [c](), [feature](), [jit](), [linux](), [macos](), [performance](), [production](), [python](), [python-3-13](), [python-3-14](), [release](), [release-schedule](), [releases](), [windows]() ### AI overview Python announces the final planned alpha of Python 3.15 alongside maintenance releases 3.14.4 and 3.13.13. The 3.15 preview highlights planned language, typing, C API, ABI, encoding, profiling, and JIT performance changes, and is not recommended for production. ### Source excerpt A final alpha and two bug fixes are awaiting your upgrade. ## Python 3.15's JIT is now back on track DevFeed: [Python 3.15's JIT is now back on track]() Original publisher: [Read original article]() Author: Ken Jin Published: 2026-03-23T00:00:00Z Content type: article Language: en Sources: [Python Insider]() Topics: [JIT](), [Python](), [Linux](), [macOS]() Tags: [article](), [blog](), [community](), [contributors](), [jit](), [linux](), [macos](), [performance](), [python]() ### AI overview Python's CPython JIT has met its performance goals ahead of schedule for macOS AArch64 and x86_64 Linux. The article discusses preliminary Python 3.15 alpha results, the JIT's recovery from earlier slowdowns, and the community-led work and contributors behind its progress. ### Source excerpt A look at Python's JIT in 3.15a7. ## Announcing chDB 4: write Pandas, run ClickHouse, now on Hex DevFeed: [Announcing chDB 4: write Pandas, run ClickHouse, now on Hex]() Original publisher: [Read original article]() Author: Ryadh Dahimene; Auxten Wang Published: 2026-03-11T10:52:16Z Content type: release Language: en Sources: [ClickHouse Blog]() Topics: [clickhouse](), [pandas](), [Data Science](), [Optimization](), [parquet](), [API](), [Compression](), [JIT](), [Jupyter Notebook]() Tags: [clickhouse](), [code](), [data](), [data-science](), [how-to](), [jit](), [learn](), [optimization](), [parquet]() ### AI overview chDB 4, launched with Hex integration, adds a Pandas-like DataStore API that executes familiar Pandas code on the in-process ClickHouse OLAP engine. The article explains how this approach addresses Pandas's eager execution and memory overhead by leveraging ClickHouse optimizations for analytical workflows. ### Source excerpt Today, we're launching chDB 4 together with HexEX, where it is available along with the new Pandas-like DataStore API as a native integration ## Python 3.15.0 alpha 7 DevFeed: [Python 3.15.0 alpha 7]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-03-10T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [JIT](), [releases](), [Compiler](), [Linux](), [macOS]() Tags: [jit](), [linux](), [macos](), [python](), [release](), [releases]() ### AI overview Python 3.15.0a7 is the seventh of eight planned alpha releases and provides an early developer preview of the in-development Python 3.15 series. It introduces or advances features including explicit lazy imports, a statistical sampling profiler, unpacking in comprehensions, UTF-8 as the default encoding, improved typing support, a new C API for bytes objects, upgraded JIT compilation, and improved error messages. ### Source excerpt The penultimate 3.15 alpha is out! ## Python 3.15.0 alpha 6 DevFeed: [Python 3.15.0 alpha 6]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-02-11T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [JIT](), [Compiler](), [GitHub]() Tags: [developer](), [features](), [github](), [jit](), [performance](), [python](), [release](), [release-schedule](), [releases]() ### AI overview Python 3.15.0a6 is an early developer preview and the sixth of eight planned alpha releases. It introduces or advances features including a statistical sampling profiler, unpacking in comprehensions, UTF-8 as the default encoding, a new C API for Python bytes objects, typed extra items, an upgraded JIT compiler, and improved error messages. ### Source excerpt This is an early developer preview of Python 3.15 www.python.org/downloads/release/python-3150a6/ Major new features of the 3.15 series, compared to 3.14 Pyt... ## Python 3.14.3 and 3.13.12 are now available! DevFeed: [Python 3.14.3 and 3.13.12 are now available!]() Original publisher: [Read original article]() Author: Thomas Wouters Published: 2026-02-03T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python 3.14](), [Python](), [releases](), [Compression](), [JIT](), [Syntax Highlighting](), [Process]() Tags: [compression](), [jit](), [performance](), [process](), [python](), [python-3-14](), [release](), [releases]() ### AI overview Python 3.14.3 is the third maintenance release in the Python 3.14 series, with around 299 bug fixes, build improvements, and documentation changes since Python 3.14.2. The article also highlights major Python 3.14 features, including free-threaded support, deferred annotation evaluation, template string literals, multiple interpreters, Zstandard support, improved debugging, an experimental JIT in official macOS and Windows binaries, and official Android binary releases. ### Source excerpt Python 3.14.3 is now available! This is third maintenance release of Python 3.14 Python 3.14.3 is the third maintenance release of 3.14, containing around ... ## Python 3.15.0 alpha 5 (yes, another alpha!) DevFeed: [Python 3.15.0 alpha 5 (yes, another alpha!)]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-01-14T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [releases](), [JIT](), [Compiler](), [Linux](), [macOS]() Tags: [community](), [documentation](), [feature](), [jit](), [linux](), [macos](), [performance](), [python](), [release](), [releases]() ### AI overview Python 3.15.0 alpha 5 is an extra early developer preview release, issued after an earlier alpha was built against the wrong date. The article outlines planned and implemented changes, including a new statistical sampling profiler, UTF-8 as the default encoding, a new C API for creating Python bytes objects, JIT compiler upgrades, improved error messages, and the upcoming alpha release schedule. ### Source excerpt Note: 3.15.0a4 was accidentally built against from 2025-12-23 instead of 2026-01-13, so this 3.15.0a5 is an extra release correctly built against 2026-01-14... ## Python 3.15.0 alpha 4 DevFeed: [Python 3.15.0 alpha 4]() Original publisher: [Read original article]() Author: Hugo van Kemenade Published: 2026-01-13T00:00:00Z Content type: release Language: en Sources: [Python Insider]() Topics: [Python](), [JIT](), [Compiler](), [releases]() Tags: [jit](), [python](), [release](), [release-schedule](), [releases]() ### AI overview Python 3.15.0 alpha 4 is an early developer preview and the fourth of seven planned alpha releases. It introduces or advances features including a statistical sampling profiler, UTF-8 as the default encoding, a new C API for creating Python bytes objects, an upgraded JIT compiler, and improved error messages. The release is not recommended for production use. ### Source excerpt Edit: This 3.15.0a4 was accidentally built against \ from 2025-12-23 instead of 2026-01-13, so 3.15.0a5 is an extra release correctly built against 2026-01-1... ## Using Ahead-of-Time Cache Optimizations in Recent JDK Releases DevFeed: [Using Ahead-of-Time Cache Optimizations in Recent JDK Releases]() Original publisher: [Read original article]() Author: Ana-Maria Mihalceanu Published: 2025-12-17T03:03:45Z Content type: tutorial Language: en Sources: [Java Advent Calendar]() Topics: [Java](), [Caching](), [JIT](), [Memory safety verification]() Tags: [2025](), [cache](), [guides](), [java](), [java-advent](), [jdk](), [jdk25](), [jit](), [jvm](), [openjdk](), [performance](), [project-leyden](), [startup]() ### AI overview This tutorial explains how to use Ahead-of-Time cache features in recent JDK releases to improve Java application startup time and warm-up performance. It covers the train, assemble, and run workflow introduced in JDK 24 and method profiling improvements in JDK 25. ### Source excerpt As the year comes to a close, turn your focus to boosting your Java application performance by applying Ahead-of-Time (AOT) cache features in recent JDK releases. This article guides you through using AOT cache optimizations in your application, thereby minimizing startup time and achieving faster peak performance. What is the Ahead-of-time cache in the jdk [...] The post Run Into the New Year with Java's Ahead-of-Time Cache Features appeared first on JVM Advent. ## Java Hello World, LLVM Edition DevFeed: [Java Hello World, LLVM Edition]() Original publisher: [Read original article]() Author: James Hamilton Published: 2025-12-07T02:02:37Z Content type: tutorial Language: en Sources: [Java Advent Calendar]() Topics: [Java](), [LLVM](), [API](), [JIT]() Tags: [2025](), [api](), [assembly](), [bytecode](), [compilers](), [java](), [java-advent](), [jdk](), [jit](), [jvm](), [llvm]() ### AI overview This tutorial shows how to use Java's Foreign Function & Memory API to call the LLVM C API, generate LLVM IR for a Hello World program, and JIT-compile it to native code. It also introduces LLVM, its IR representations, and local installation on Ubuntu or Debian. ### Source excerpt After exploring Java bytecode in previous years (2022, 2023, 2024), this year we'll take an unexpected detour for a Java advent: instead of generating Java bytecode, we'll use Java to build and execute LLVM IR, the intermediate language behind compilers like clang. Using Java's Foreign Function & Memory (FFM) API, we'll call the LLVM C [...] The post Java Hello World, LLVM Edition appeared first on JVM Advent. ## Compiling Ruby To Machine Language DevFeed: [Compiling Ruby To Machine Language]() Original publisher: [Read original article]() Author: Pat Shaughnessy Published: 2025-11-17T00:00:00Z Content type: article Language: en Sources: [Pat Shaughnessy]() Topics: [Ruby](), [JIT](), [Compiler](), [Assembly](), [Code]() Tags: [compiler](), [jit](), [machine](), [performance](), [ruby](), [rust](), [updating-ruby-under-a-microscope]() ### AI overview This excerpt explains how Ruby's YJIT compiler identifies frequently called functions and blocks, counts executions, and compiles hot YARV instruction sequences into machine language. It also describes thresholds used for small Ruby programs and Ruby on Rails web applications, along with YJIT blocks. ### Source excerpt I've started working on a new edition of Ruby Under a Microscope that covers Ruby 3.x. I'm working on this in my spare time, so it will take a while. Leave a comment or drop me a line and I'll email you when it's finished. Here's an excerpt [Next page]()