To run a JavaScript program, the source text needs to be processed so V8 can understand it. V8 starts out by parsing the source into an abstract syntax tree (AST), a set of objects that represent the program structure. That AST gets compiled to bytecode by Ignition. The performance of these parse + compile phases is important: V8 cannot run code before compilation is done. In this series of blog posts, we focus on parsing, and the work done in V8 to ship a blazingly fast parser.

Every six weeks, we create a new branch of V8 as part of our release process. Each version is branched from V8’s Git master immediately before a Chrome Beta milestone. Today we’re pleased to announce our newest branch, V8 version 7.4, which is in beta until its release in coordination with Chrome 74 Stable in several weeks. V8 v7.4 is filled with all sorts of developer-facing goodies. This post provides a preview of some of the highlights in anticipation of the release.

V8 v7.4 now supports JavaScript execution without allocating executable memory at runtime.

In its default configuration, V8 relies heavily on the ability to allocate and modify executable memory at runtime. For example, the TurboFan optimizing compiler creates native code for hot JavaScript (JS) functions just-in-time, and most JS regular expressions are compiled down to native code by the irregexp engine. Creating executable memory at runtime is part of what makes V8 fast.

Every six weeks, we create a new branch of V8 as part of our release process. Each version is branched from V8’s Git master immediately before a Chrome Beta milestone. Today we’re pleased to announce our newest branch, V8 version 7.3, which is in beta until its release in coordination with Chrome 73 Stable in several weeks. V8 v7.3 is filled with all sorts of developer-facing goodies. This post provides a preview of some of the highlights in anticipation of the release.

Over the past years the V8 garbage collector (GC) has changed a lot. The Orinoco project has taken a sequential, stop-the-world garbage collector and transformed it into a mostly parallel and concurrent collector with incremental fallback.

Every six weeks, we create a new branch of V8 as part of our release process. Each version is branched from V8’s Git master immediately before a Chrome Beta milestone. Today we’re pleased to announce our newest branch, V8 version 7.2, which is in beta until its release in coordination with Chrome 72 Stable in several weeks. V8 v7.2 is filled with all sorts of developer-facing goodies. This post provides a preview of some of the highlights in anticipation of the release.

During his three-months internship on the V8 team, Hai Dang worked on improving the performance of [...array], [...string], [...set], [...map.keys()], and [...map.values()] (when the spread elements are at the start of the array literal). He even made Array.from(iterable) much faster as well. This article explains some of the gory details of his changes, which are included in V8 starting with v7.2.

Asynchronous processing in JavaScript traditionally had a reputation for not being particularly fast. To make matters worse, debugging live JavaScript applications — in particular Node.js servers — is no easy task, especially when it comes to async programming. Luckily the times, they are a-changin’. This article explores how we optimized async functions and promises in V8 (and to some extent in other JavaScript engines as well), and describes how we improved the debugging experience for async code.

Every six weeks, we create a new branch of V8 as part of our release process. Each version is branched from V8’s Git master immediately before a Chrome Beta milestone. Today we’re pleased to announce our newest branch, V8 version 7.1, which is in beta until its release in coordination with Chrome 71 Stable in several weeks. V8 v7.1 is filled with all sorts of developer-facing goodies. This post provides a preview of some of the highlights in anticipation of the release.

Every six weeks, we create a new branch of V8 as part of our release process. Each version is branched from V8’s Git master immediately before a Chrome Beta milestone. Today we’re pleased to announce our newest branch, V8 version 7.0, which is in beta until its release in coordination with Chrome 70 Stable in several weeks. V8 v7.0 is filled with all sorts of developer-facing goodies. This post provides a preview of some of the highlights in anticipation of the release.