Significantly slower tests in pipelines on Node 22

[bakasmarius]

Describe the bug

We have a NestJS backend project (~20k LOC) with 652 tests in 199 test files.
It's a mix of unit and integration tests (nothing fancy, just RabbitMQ and PostgreSQL).
We finally got a chance to upgrade from Node 20 to Node 22 but we noticed that tests are taking ~10 times more time to run on Bitbucket Pipelines (we use 8x size) after simply changing the image from node:20.18.1-alpine3.21 to node:22.13.0-alpine3.21.
We are also in the process of migrating from Bitbucket to Gitlab, the difference in Gitlab between node versions is only ~+35% (~2 minutes), but the total time is quite similar.
There is no significant difference between node versions when running tests locally on Windows or Mac laptops.
There is also no significant difference between running tests using vitest v2 or v3.
I also tried running the tests on the newest Node 23, the numbers are basically the same as with Node 22.
Here is a table of time differences (Mac times are approximated as they came from my coworker):

	Node: 20.18.1	Node: 22.13.0	Diff (seconds)	Diff (%)
Windows 11 laptop (32 GB RAM)	160	179	19	11.88%
Mac M1 laptop	60	60	0	0.00%
Mac M4 laptop	40	40	0	0.00%
Bitbucket Pipelines Self-Hosted	330	328	-2	-0.61%
Bitbucket Pipelines 8x	52	574	522	1003.85%
Bitbucket Pipelines 4x	116	579	463	399.14%
Bitbucket Pipelines 2x	286	765	479	167.48%
Bitbucket Pipelines	745	869	124	16.64%
Gitlab Pipelines	379	509	130	34.30%

Is this expected? Maybe someone else had the same experience and knows if there's something we can do to keep the numbers lower?

Reproduction

System Info

Node: 20.18.1 vs. 22.13.0
Windows 11 / MacOS
Bitbucket Pipelines
Gitlab Pipelines

Used Package Manager

npm

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[sheremet-va]

Can you check if fixes from #7285 work for you?

[AriPerkkio]

That likely won't help as summary is disabled on CI.

I would recommend to try narrowing down the exact Node versions where the slowness starts coming up and then check the Node release notes for that. Is it happening on 22.0.0 too or just the mentioned 22.13.0?

[bakasmarius]

@sheremet-va no, as @AriPerkkio correctly stated, summary is disabled on CI, although I managed to speed up my local tests by replacing dot reporter with default reporter 🙂

@AriPerkkio good idea!! I made some tests and looks like the change happened with Node 22.12.0 - I guess enabling require(esm) by default might probably be the cause of it
https://github.com/nodejs/node/blob/main/doc/changelogs/CHANGELOG_V22.md#2024-12-03-version-22120-jod-lts-ruyadorno

[github-actions]

Hello @bakasmarius. Please provide a minimal reproduction using a GitHub repository or StackBlitz (you can also use examples). Issues marked with needs reproduction will be closed if they have no activity within 3 days.

[bakasmarius]

@hi-ogawa I am not sure what kind of reproduction I could provide, could you elaborate, please?
I am of course not able to share the repo from my work, but I guess any open-source repo with a couple hundred of tests would do. Even tests from vitest repo should suffice.

[hi-ogawa]

On our CI, there doesn't seem to be a significant gap between Node 20 vs 22. So at the moment, I don't think we have any idea what to tackle. We need a reproduction for the issue to be actionable and otherwise, we need to move on and prioritize other issues for now.