Improved memory efficiency for WebAssembly Workers
FinalizationRegistry ↗ is now available in Workers. You can opt-in using the enable_weak_ref compatibility flag.
This can reduce memory leaks when using WebAssembly-based Workers, which includes Python Workers and Rust Workers. The FinalizationRegistry works by enabling toolchains such as Emscripten ↗ and wasm-bindgen ↗ to automatically free WebAssembly heap allocations. If you are using WASM and seeing Exceeded Memory errors and cannot determine a cause using memory profiling, you may want to enable the FinalizationRegistry.
For more information refer to the enable_weak_ref compatibility flag documentation.
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