eslint-plugin-react: [Bug]: Performance Regression

Is there an existing issue for this?

I have searched the existing issues and my issue is unique
My issue appears in the command-line and not only in the text editor

Description Overview

Upgrading from 7.33.1 to 7.33.2 causes a few rules to slow down significantly.

A few rules that appear to have gotten significantly slower are:

react/no-array-index-key
react/no-unstable-nested-components
react/no-danger-with-children

Our overall linting time goes from ~60s to ~90s only changing this one package.

Using eslint timing settings you can see here that these two rules are occupying a good amount of time relative to before the upgrade.

7.33.2:

react/no-array-index-key              | 21522.183 |    30.7%
react/no-unstable-nested-components   |  7283.991 |    10.4%
react/no-danger-with-children         |  2138.971 |     3.0%

7.33.1:

react/no-array-index-key              |   718.943 |     1.8%
react/no-unstable-nested-components   |  1208.373 |     3.0%
react/no-danger-with-children         |  Not slow enough to be in top 10

Pertinent package versions:

eslint: 8.46.0 & 8.47.0
eslint-plugin-react: 7.33.2
@typescript-eslint/eslint-plugin: 6.2.1 & 6.4.1
@typescript-eslint/parser: 6.2.1 & 6.4.1
Node.js: 18.16.1
Mac OS 13.5 - M1 MBP

Unfortunately I can’t share our codebase and I don’t have a reproduction. Hopefully the code diff between .1 and .2 are small enough to be able to track down this regression.

Expected Behavior

I expect the two versions to be similar in speed.

eslint-plugin-react version

7.33.2

eslint version

8.47.0

node version

18.16.1

About this issue

Original URL
State: closed
Created 10 months ago
Reactions: 1
Comments: 20 (12 by maintainers)

Commits related to this issue

[Fix] stop mutating node 4+ Iterator.prototype with Symbol.toStringTag This causes a huge performance deoptimization. See https://github.com/jsx-eslint/eslint-plugin-react/issues/3619 — committed to ljharb/Iterator.prototype by ljharb 10 months ago

Most upvoted comments

@ljharb the update in https://github.com/ljharb/safe-array-concat/issues/2 fixes the issue.

The change to iterator.prototype either has very little effect but is probably a good change anyway.

jleider on Sep 6, 2023

Using 7.33.2 and iterator.prototype 1.1.1 it helps a little. Down from ~89s to ~78-80s but still not back down to the ~55-59s range as 7.33.1.

Rule                                  | Time (ms) | Relative
:-------------------------------------|----------:|--------:
react/no-array-index-key              | 17831.444 |    28.9%
redos/no-vulnerable                   | 11373.265 |    18.4%
@typescript-eslint/no-unsafe-argument | 11122.301 |    18.0%
react/no-unstable-nested-components   |  6134.390 |     9.9%
import/no-duplicates                  |  5302.239 |     8.6%
react/no-danger-with-children         |  1932.733 |     3.1%
@typescript-eslint/no-redeclare       |   849.440 |     1.4%
@typescript-eslint/no-unused-vars     |   689.812 |     1.1%
camelcase                             |   562.923 |     0.9%
simple-import-sort/imports            |   428.665 |     0.7%

________________________________________________________
Executed in   80.72 secs    fish           external
   usr time   98.35 secs   33.00 micros   98.35 secs
   sys time    6.36 secs  356.00 micros    6.36 secs

jleider on Aug 31, 2023

Awesome 😃 I’ll close this then. Thanks for helping me debug!

ljharb on Sep 6, 2023

Thanks, I’ll keep looking for more root causes.

ljharb on Aug 31, 2023

Starting with 7.33.1

importing const i = require("iterator.prototype"); in Components.js exhibits no change in run time.
importing const map = require('es-iterator-helpers/Iterator.prototype.map'); in Components.js causes the slowdown.

In each case, I only imported, the import was never referenced.

jleider on Aug 31, 2023

This has been filed on v8 as https://bugs.chromium.org/p/chromium/issues/detail?id=1477372.

ljharb on Aug 30, 2023

Turns out this is caused by https://npmjs.com/iterator.prototype (which is my own package) - specifically, v8 seems to have a huge deopt when Symbol.toStringTag is added onto %Iterator%.prototype.

I’ll publish a fix to that package, and potentially to es-iterator-helpers as well, at which point I’ll close this.

ljharb on Aug 30, 2023

This is the commit causing the slowdowns: https://github.com/jsx-eslint/eslint-plugin-react/commit/e1dd37f743649bf43726fe102a16bc71062d8687

The es iterator shims clearly aren’t as performant as the built-in array functions.

jleider on Aug 25, 2023