xo --fix very slow

[StarpTech]

Reproduction

Run npm run lint:fix in https://github.com/StarpTech/apollo-datasource-http

Running on around ~5 files takes more than a second on very performant hardware.

Constraints

• AMD Ryzen 9 5950X 16-Core Processor, 3401 Mhz, 16 Core(s), 32 Logical Processor(s),
• 64GB RAM 3000Mhz
• NVMe
• Ubuntu (WSL2)

❯ time xo --fix
xo --fix  2.96s user 0.21s system 149% cpu 2.127 total

[sindresorhus]

The main problem is that TypeScript ESLint (and TypeScript) is very slow, and I did notice it got extra slow in the past few months. I haven't yet had the time to dig into what caused it.

---

Also seems like the prettier config slow things down:

❯ TIMING=1 xo --fix
Rule                                             | Time (ms) | Relative
:------------------------------------------------|----------:|--------:
prettier/prettier                                |   344.571 |    40.9%
ava/no-import-test-files                         |    93.161 |    11.0%
@typescript-eslint/no-floating-promises          |    87.586 |    10.4%
@typescript-eslint/return-await                  |    56.237 |     6.7%
import/namespace                                 |    48.292 |     5.7%
@typescript-eslint/no-confusing-void-expression  |    33.194 |     3.9%
@typescript-eslint/no-unused-vars                |     8.934 |     1.1%
unicorn/prefer-string-slice                      |     6.955 |     0.8%
@typescript-eslint/no-unnecessary-type-assertion |     6.687 |     0.8%
@typescript-eslint/await-thenable                |     5.755 |     0.7%

[StarpTech]

Thanks for the quick evaluation. I'll try to disable prettier.

[StarpTech]

Also seems like the prettier config slow things down:

The sum doesn't reflect the execution time. Is there a way to enable other metrics?

I disabled prettier but it has no significant impact compared to total.

❯ time TIMING=1 xo --fix
Rule                                            | Time (ms) | Relative
:-----------------------------------------------|----------:|--------:
prettier/prettier                               |   357.208 |    40.7%
@typescript-eslint/no-floating-promises         |   101.728 |    11.6%
ava/no-import-test-files                        |    63.628 |     7.2%
@typescript-eslint/return-await                 |    56.333 |     6.4%
@typescript-eslint/no-confusing-void-expression |    45.433 |     5.2%
import/namespace                                |    30.714 |     3.5%
@typescript-eslint/no-unused-vars               |    13.589 |     1.5%
unicorn/prefer-string-slice                     |     9.937 |     1.1%
@typescript-eslint/await-thenable               |     8.130 |     0.9%
@typescript-eslint/no-unnecessary-qualifier     |     7.865 |     0.9%
TIMING=1 xo --fix  4.35s user 0.22s system 149% cpu 3.062 total

[sindresorhus]

Is there a way to enable other metrics?

No, the metrics are provided by ESLint and is about rule-only performance.

[sindresorhus]

To get any other metrics, someone will need to run the XO run in DevTools and look at the flame graph.

[fregante]

Tracking in #515