generateMetadata() in root layout.tsx is called on every navigation

[kevinmitch14]

Link to the code that reproduces this issue

https://github.com/kevinmitch14/reproduction-app

To Reproduce

Go to page /1 and continue to navigate through pages via Link (1, 2, 3, 4...)

Current vs. Expected behavior

Behaviour:
When using fetch, results in generateMetadata() are the same on every refresh/navigation.
When not using fetch() or adding a an artificial delay, the computation is done on every page navigation.

Expectations:
generateMetadata() in layout.tsx is not called on every navigation. Similar to how layout.tsx does not re-render/re-fetch on navigation.

Context: I want to display a metadata icon based on the route. I need to fetch the image from a remote DB. This image does not change, it only needs to be fetched in root layout. I am not using fetch

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.0.0: Fri Sep 15 14:41:43 PDT 2023; root:xnu-10002.1.13~1/RELEASE_ARM64_T6000
Binaries:
  Node: 20.9.0
  npm: 10.1.0
  Yarn: 1.22.19
  pnpm: 8.15.1
Relevant Packages:
  next: 14.1.1-canary.57 // Latest available version is detected (14.1.1-canary.57).
  eslint-config-next: N/A
  react: 18.2.0
  react-dom: 18.2.0
  typescript: 5.1.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Metadata (metadata, generateMetadata, next/head)

Which stage(s) are affected? (Select all that apply)

next dev (local), next start (local)

Additional context

I also have another issue filed at #62162. Would be good to clarify if cache() is relevant to generateMetadata(). It seems it is from the docs, but it is not clear if generateMetadata() has access to the cache context.

[ViKi10000]

can i work on this?