feat(gatsby): add DANGEROUSLY_DISABLE_OOM

[wardpeet]

Description

This adds a process.env variable called DANGEROUSLY_DISABLE_OOM to disable saving the redux state to disk. This helps with going out of memory in the bootstrap phase. The downside is that your build will be much slower as it will always build from a clean dir.

We won't put this variable inside our docs as it's a feature we don't want to highlight or people to use.

Related Issues

#12485

[KyleAMathews]

Is this intended as a temporary hack? E.g. once v8.seralize stuff gets figured out we remove this?

[muescha]

i would add it anyhow to documentation with an big warning to avoid more and more "hidden preferences" or avoid some surprising behavior.

anyhow it would name it somehow what it do and not what it avoid DANGEROUSLY_DISABLE_SAVING_REDUX_STATE

[pieh]

Yes it's meant to be temporary. Users are blocked on OOM issues and until v8.serialize land, there is nothing they can do to unblock themselves (other than monkey patching and commenting out JSON.stringify parts in saveState function.

@muescha This is intentionally not mentioning redux state. We don't want to encourage using it for the purpose of skipping redux state caching (as then we can never fix cache issues if users don't use it at all). This is only to unblock cases of out of memory issues. This will also be removed once proper fix is merged.

[wardpeet]

Yes temporary yes. Let me just remove the analytics and get this merged.

[muescha]

maybe comment in code why its temporary and what it solves ... just to see it later in code reviews and don't forget to remove it later

[DSchau]

@wardpeet I'm gonna pick up this PR and add some documentation if that's cool!

[DSchau]

Going to get this merged.

For context, I added a Scaling Issues document that we can link to if people are running into issues that this temporary feature may fix.

Longer term--let's make this document (and flag!) redundant and delete it/tweak the content after we land fixes re: #6656, #12566, and #12343.