SolidJS Creator on Signals: 'Surgical, Not Brute Force'
In a recent discussion, SolidJS creator Ryan Carniato explained the performance advantage of signals-based reactivity. "Signals let you sidestep unnecessary work—it's surgical, not brute force," he said. Carniato attributed the 10-20x faster benchmarks in UI updates to signals' ability to make precise, minimal changes without traversing entire component trees, unlike traditional state models.
- Benchmarks comparing SolidJS with React's Virtual DOM have shown signals can reduce DOM mutations by up to 99.9%, lower memory usage by over 70%, and decrease update latency by as much as 94%. - Unlike React components which re-run their entire function on state changes, SolidJS components execute only once to set up the view. Subsequent updates are handled by the signal graph, which directly modifies the specific DOM elements that have changed. - The upcoming React Compiler (formerly React Forget) aims to achieve performance gains similar to signals by automatically memoizing components at build time, thus preventing unnecessary re-renders without requiring developers to adopt the signal pattern directly. - The trend towards signals is visible across the industry, with frameworks like Angular, Preact, and Qwik integrating them as a core part of their reactivity model. - Fine-grained reactivity systems are built on two core primitives: an observable (or "signal") to hold a value, and a computed (or "effect") that reacts to changes in that value. - To handle UI consistency with asynchronous operations, SolidJS uses a primitive called `Transitions`, which marks certain updates as non-urgent to prevent visual "tearing" where one piece of data updates before another. - A formal "JavaScript Signals" proposal is under consideration by ECMA TC39, which could lead to a standardized, native implementation of reactive primitives within the JavaScript language itself. - From a developer experience perspective, signals can simplify state management by eliminating the need for manual dependency arrays (like in `useEffect`) and reducing the cognitive load of tracking component re-renders.
