Building schema step taking significantly longer under gatsby 3 than gatsby 2.3

Description

Data source: Contentful

The Building Schema step is taking longer than expected to finish often more than 90 seconds this is significantly longer than the same data source under gatsby 2

Steps to reproduce

Check out https://github.com/grgcnnr/gatsby-ctf-build-schema-test (contentful access token is hard coded into config) npm install gatsby build

Expected result

Previous schema build steps under gatsby 2.3x were taking approximately 20 seconds

I would hope similar performance would be achievable

Actual result

Building Schema step consistently takes more than 80 seconds.

Environment

Minimum repro:

    OS: macOS 11.3.1
    CPU: (12) x64 Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 14.16.1 - ~/.nvm/versions/node/v14.16.1/bin/node
    npm: 6.14.12 - ~/.nvm/versions/node/v14.16.1/bin/npm
  Languages:
    Python: 2.7.16 - /usr/bin/python
  Browsers:
    Chrome: 90.0.4430.212
    Edge: 90.0.818.62
    Safari: 14.1
  npmPackages:
    gatsby: ^3.4.1 => 3.4.1
    gatsby-plugin-gatsby-cloud: ^2.4.1 => 2.4.1
    gatsby-plugin-image: ^1.4.0 => 1.4.0
    gatsby-plugin-manifest: ^3.4.0 => 3.4.0
    gatsby-plugin-offline: ^4.4.0 => 4.4.0
    gatsby-plugin-react-helmet: ^4.4.0 => 4.4.0
    gatsby-plugin-sharp: ^3.4.1 => 3.4.1
    gatsby-source-contentful: ^5.5.0 => 5.5.0
    gatsby-source-filesystem: ^3.4.0 => 3.4.0
    gatsby-transformer-sharp: ^3.4.0 => 3.4.0
  npmGlobalPackages:
    gatsby-cli: 3.5.0

[axe312ger]

@grgcnnr I am preparing a new major version which should reduce schema generation overhead drastically, especially for complex/large projects. Feel free to follow #31385 to get updated as soon the canary is ready 😃

[axe312ger]

I know it is easier to say as to do 🙈