🐛 Biome VSCode plugin uses 99% of CPU

[BakirGracic]

VS Code version

1.104.0 (latest as of writing)

Extension version

2025.7.41733 (latest as of writing)

Biome version

2.2.4 (latest as of writing)

Operating system

• Windows
• macOS
• Linux

Description

Biome VSCode extension uses 99% of CPU after a while, possible memory too...

Steps to reproduce

• MacBook Air M4
• MacOS Tahoe 26 (experienced issue on Developer Beta version, persists in official release)
• fresh VSCode installation (v1.104.0 - latest as of writing)
• fresh Biome VSCode plugin installation (v2025.7.41733 and Biome v2.2.4 - both latest as of writing)
• default NextJS 15.5.4 Biome configuration file
• VSCode default formatter -> Biome
• VSCode formatOnSave -> true

Expected behavior

normal CPU usage, no "leaks" or "excessive processes"

Does this issue occur when using the CLI directly?

Not sure / Not applicable

Link to a minimal reproduction

No response

Logs

[BakirGracic]

ChatGPT 5 Thinking + Web Search suggested changing this

"linter": {
    "domains": {
      "project": "none",   // turn off heavy project-level rules
      "next": "recommended",
      "react": "recommended"
    }
  }

if someone tests this and it works, please notify. i will stick to JS CLI due to limited time

[scott-joe]

Just did some digging to figure out why my M1 was feeling "warm" on my lap for the first time since I got it a few years ago. Looking at Activity Monitor, I saw biome was using 165% of my CPU and gigs of RAM. Looking the process' details, it was spawned by VSCode in a project directory that wasn't configured to use Biome. Disabling that VSCode extension for this workspace solved it, but that's clearly not a good behavior.

[Hassan4Dev]

I'm using it in a monorepo, and was having the same issue with excessive CPU usage, I was able to solve it by controlling what files it looks at:

  "files": {
    "includes": [
      "**",
      "!**/node_modules",
      "!**/dist",
      "!**/.turbo",
      "!**/.next"
    ]
  },

Issue started after I switched to built packages, so I think the dist/ folder is the main culprit, I'd give this a try.

[BakirGracic]

Issue started after I switched to built packages, so I think the dist/ folder is the main culprit, I'd give this a try.

this is the default "files" Biome configuration that NextJS ships

"files": {
  "ignoreUnknown": true,
  "includes": ["**", "!node_modules", "!.next", "!dist", "!build"]
},

it excludes the same directories (except the turbo dir), but with ** wildcard since you are using the monorepo setup.

this to me seems like an identical setup. maybe there is something more than files config in play

i will be revisiting this problem soon, and will probably leave some updates.

thank you both for sharing

[scott-joe]

If it helps, this is what was in the process info (redacted obv):

/Users/xxxxx/xxxxx/xxxxx/xxxxx
/Users/xxxxx/Library/Application Support/fnm/node-versions/v20.12.1/installation/lib/node_modules/@biomejs/biome/node_modules/@biomejs/cli-darwin-arm64/biome
/usr/lib/dyld
/Library/Preferences/Logging/.plist-cache.MDShjR7C
->0x42df1aa037c188d5
->0xe0690576edad57f0
->0x447f2d387ec26528
/Users/xxxxx/Library/Caches/dev.biomejs.biome/biome-logs/server.log.2025-09-28-18
count=0, state=0xa
count=0, state=0xa
count=0, state=0xa
->0xb1a67f2dc7ccba28
->0xdb76dc8cd63f6dcc
->0xb1a67f2dc7ccba28
/Users/xxxxx/Library/Caches/dev.biomejs.biome/biome-socket-2.2.0
/Users/xxxxx/Library/Caches/dev.biomejs.biome/biome-socket-2.2.0

[scott-joe]

Before I disable this extension:

After. That kernel_task disappears as soon as I disable the extension as well.

[BakirGracic]

Yep. Very similar with me.

Do you have "Configuration Path" setting for Biome modified? I reinstalled the extension on the exact same setup and only changed that setting. I don't have any issues and plugin works as normal

Can you please check with that?

[BakirGracic]

Happy to share that there is no high CPU/mem usage anymore (on my setup at least)

As said in my previous comment, I reinstalled the plugin and developed for 4 hours with no problems.

The only thing that got changed was Biome config path settings option to default value.

I'm not 100% sure was that setting the culprit or the new version that may have gotten eventually released, but nonetheless it works as intended now.

I noticed this issue didn't get maintainers' recognition, so I will mark it as closed. Thank you all for your contributions