Vue version

3.5.32

Link to minimal reproduction

https://github.com/bgarcias-cp/nuxt-v4-memory-leak

Steps to reproduce

Steps to reproduce the memory leak:

1. Clone the repo and install dependencies.
2. Build the project: npm run build.
3. Launch the server: node --inspect .output/server/index.mjs.
4. Run load test: autocannon -c 10 -d 20 http://localhost:3000/.

Result:
Memory footprint grows from 13.7 MB to 122 MB. The leak persists even after garbage collection.

There are numerous string objects holding references to EffectScope, specifically originating from reactivity.cjs.prod.js and runtime-core.cjs.prod.js

What is expected?

Memory usage should remain stable after the load test finishes, and any temporary objects should be cleared by the garbage collector, returning the heap size to near-baseline levels.

What is actually happening?

uring the load test, memory usage scales linearly with the number of requests, increasing from 13.7 MB to 122 MB. Analysis of the heap snapshot reveals a large accumulation of string objects that maintain active references to EffectScope. These references are traced back to reactivity.cjs.prod.js:15 and runtime-core.cjs.prod.js:6450, suggesting that scopes are not being properly disposed of after the request lifecycle, even when the garbage collector is manually triggered.

System Info

System:
    OS: macOS 15.7.4
    CPU: (10) arm64 Apple M2 Pro
    Memory: 95.27 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.20.0 - /Users/b.garcias_cyberpuert/.nvm/versions/node/v20.20.0/bin/node
    npm: 10.8.2 - /Users/b.garcias_cyberpuert/.nvm/versions/node/v20.20.0/bin/npm
    pnpm: 10.33.0 - /Users/b.garcias_cyberpuert/.nvm/versions/node/v20.20.0/bin/pnpm
  Browsers:
    Chrome: 147.0.7727.55
    Firefox: 147.0.1
    Firefox Developer Edition: 149.0
    Safari: 18.6
  npmPackages:
    vue: 3.5.32 => 3.5.32

Any additional comments?

No response