vitest: tests run 3x slower than Jest

Describe the bug

Tests run 3x slower than Jest for me.

Reproduction

vitest: https://github.com/sachinraja/zod-to-ts/tree/vitest jest: https://github.com/sachinraja/zod-to-ts/tree/main

System Info

System:
    OS: Linux 5.15 Pop!_OS 21.10
    CPU: (8) x64 Intel(R) Core(TM) i7-10510U CPU @ 1.80GHz
    Memory: 5.03 GB / 15.44 GB
    Container: Yes
    Shell: 5.8 - /usr/bin/zsh
  Binaries:
    Node: 16.11.1 - ~/.asdf/installs/nodejs/16.11.1/bin/node
    Yarn: 1.22.15 - ~/.asdf/installs/nodejs/16.11.1/.npm/bin/yarn
    npm: 8.0.0 - ~/.asdf/plugins/nodejs/shims/npm
  Browsers:
    Brave Browser: 96.1.33.106
    Firefox: 95.0
  npmPackages:
    vite: 2.7.4 => 2.7.4 
    vitest: 0.0.100 => 0.0.100

Used Package Manager

pnpm

Validations

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About this issue

Original URL
State: closed
Created 3 years ago
Comments: 15 (15 by maintainers)

Most upvoted comments

@sachinraja Tests are taking ~800ms now. And with threads disabled ~650ms.

Demivan on Dec 30, 2021

I saw that threads are slower too. Alter checking it with nodejs profiler I can see that workers are idling a lot. Will investigate where bottleneck is.

Demivan on Dec 31, 2021

If it helps, I’ve added vitest to my benchmarking repo here which has a collections of unit tests which run against jasmine, jest and vitest. In my benchmarks, I’m seeing vitest perform about 2x slower than Jest and nearly 4x slower than Jasmine.

EvHaus on Dec 29, 2021

Profiled this issue. Most of the time is spent in vite doTransform. The biggest bar it transforming typescript. It is a dependency of zod-to-ts.

@antfu Shouldn’t default deps.external option prevent vitest from transforming stuff in node_modules?

Demivan on Dec 28, 2021