Drastic increase in build and warm up times when upgrading to 3.9.0

[TimGuendel]

Environment

- Operating System: Windows_NT
- Node Version:     v18.18.2
- Nuxt Version:     3.8.2
- CLI Version:      3.10.0
- Nitro Version:    2.8.1
- Package Manager:  yarn@3.6.4
- Builder:          -
- User Config:      telemetry, experimental, devtools, components, app, nitro, imports, vite, css, modules, pinia, image, proxy, runtimeConfig
- Runtime Modules:  @vueuse/nuxt@10.7.0, @pinia/nuxt@0.5.1, nuxt-jsonld@2.0.8, @nuxt-alt/proxy@2.4.9, @nuxt/image@1.1.0
- Build Modules:    -

Reproduction

I tried, but it does not really show with an empty project 🤔
3.8.2 https://stackblitz.com/edit/github-r32mz1-hj5c5o?file=package.json
3.9.0 https://stackblitz.com/github/nuxt/starter/tree/v3/?file=package.json

Describe the bug

My (large) project:
3.8.2:

3.9.0:

Switching back to 3.8.2 leads to the shorter loading times again.

Additional context

No response

Logs

No response

[stackblitz]

Start a new pull request in StackBlitz Codeflow.

• github-r32mz1-hj5c5o (Open reproduction)

[github-actions]

Would you be able to provide a reproduction? 🙏

More info

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[manniL]

Would be nice to see if it is based on the amount of components or something else triggeres the high build time. Can you try to repro?

Without a repro I don't think we can do much here as it can be any kind of module or similar 🙈

[danielroe]

We'd definitely want to tackle this if you can provide a reproduction.

Can you try installing vite v5 in your Nuxt 3.8.2 project, to see whether that's the cause? It should be completely compatible, but you'll need to use npm/pnpm/yarn resolutions/overrides.

[TimGuendel]

We'd definitely want to tackle this if you can provide a reproduction.

Can you try installing vite v5 in your Nuxt 3.8.2 project, to see whether that's the cause? It should be completely compatible, but you'll need to use npm/pnpm/yarn resolutions/overrides.

I could not find any information on how to do this. Simply using "overrides": { "vite": "5.0.11" }, did not do anything.

• How can I force Nuxt 3.8.2 to use Vite 5?
• How can I make sure it is indeed using Vite 5?

[TimGuendel]

All right, @manniL helped me 👍 (using resolutions instead of overrides did the trick 🤷‍♂️)

Vite 5 seems to be the culprit indeed:

[danielroe]

It would be great to have a reproduction. Hopefully this is something we can solve in vite. 🙏

[danielroe]

One thing - when you set vite.warmupEntry to false, this should disappear (as it disables the 'in-advance' warmup). I'd be interested to know, however, if your initial browser request to your site is a similar length of time.

[TimGuendel]

One thing - when you set vite.warmupEntry to false, this should disappear (as it disables the 'in-advance' warmup). I'd be interested to know, however, if your initial browser request to your site is a similar length of time.

So I did some tests and took screenshots of the nitro console and the browser timeline in the network tab. I waited for all chunks to be loaded:

3.8.2 with warmupEntry true

3.8.2 with warmupEntry false

3.9.0 with warmupEntry true

3.9.0 with warmupEntry false

[danielroe]

cc: @antfu would love your thoughts on this

[antfu]

From the glance I can't really tell what's the cause. I think we still need a minimal reproduction to move forward

[rolf-koizumi-ecdb]

Sorry about my comment yesterday (which I deleted) - I didn't notice that one of my projects was modified, leading to false results.
I have debugged again, and these are my current findings, though I might have made mistakes again.

• In our project with nuxt@3.9.1, warmup() is called for more urls than in nuxt@3.8.2.
• The increased number of calls happen when isServer === false.
• This return statement in warmup.ts is called way less in nuxt@3.9.1/vite@5.0.11 with isServer === false than in nuxt@3.8.2/vite@4.5.1.
  • For our project, in warmup() when env.isClient === true, vite@5.0.11 returns m.transformResult === null and m.transformResult === null for all modules, so this early return is never called.
  • With vite@4.5.1, m.transformResult.code sometimes has a value, so the return statement is called sometimes, leading to less iterations of warmup().

Alltogether, I have ~2104 calls of warmup() with nuxt@3.8.2 and ~5936 calls of warmup() with nuxt@3.9.1 which makes me think that maybe the increased number of calls is the sole reason for longer warmup times.
Though Nitro build time is 2331 ms vs. 32309 ms for me, so maybe there's more going on.

I tried looking into vites' server.moduleGraph.getModuleByUrl() but haven't found out where transformResult.code is set, what it represents and if anything has changed there.
And sorry for still not providing a minimal reproduction. If these sorts of debugging do not help I will concentrate more on getting a minimal reproduction.

[TimGuendel]

Was this helpful at all, or is there something else I could try to help solving this issue? 🤔

[TimGuendel]

@manniL suggested that I "empty" my templates and try again. We have +/-350 vue files and I replaced all templates by <template><div>Hello</div></template>

These are the startup times:

Although significantly decreased, the build time with Nuxt 3.9.3 is almost double the time it took with Nuxt 3.8.2.
The warm up times also increased by a lot.

EDIT: I ended up stripping away most of the code, keeping "only" empty components. The built time got much better, but the warmup times were always worse with 3.9.3. So it appears that the number of files has a direct effect on the warmup time 🤔

[TimGuendel]

So this issue seems to be resolved with 3.11.1... closing this.

[danielroe]

Fantastic! 🎉