perf(css): improve postcss config resolve #12484
Merged
+22
−31
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Description
With many parallel CSS file requests (especially with
preTransformRequest
), each CSS will try to resolve thepostcss
config because the cache has not been filled. This is slow as we only need one CSS file to resolve it, while others can wait for that one result. Otherwise all CSS files will resolve their own postcss config at once, causing slowness.On top of that,
postcss-load-config
takes strangely long to load (2s for me), especially if you don't have a config at all. So we need to reduce calling it.This PR does the above by caching the promise of the config resolve, instead of it's result.
Additional context
Debugging the slowness in https://github.com/sveltejs/vite-plugin-svelte/tree/main/packages/playground/big
What is the purpose of this pull request?
Before submitting the PR, please make sure you do the following
fixes #123
).