High CPU usage caused by file watcher #303702
Description
Type: Bug
I've seen other issues about this, but they're all closed and locked. All of the ones I found were about projects with a Typescript workspace, and the suggestion was to disable a switch on the TS language server options; However, I'm working with a flutter project (and I don't target web).
Just like in those issues, I don't really know how to offer a repro, as this bug happened only a few times, seemingly at random. What I do know is that something triggers it and, when that happens, file-watcher starts using 100% of a single thread whenever VS is in the background. If I bring VS back to the foreground, the CPU usage decreases significantly, albeit still higher than normal. As soon as I alt-tab, it starts again. I don't mind the slightly higher CPU usage tbh, but the fact it's concentrated on a single thread means it creates a hotspot, the CPU gets very hot very fast and fans spin up really loudly.
Looking at the Process Explorer inside VS, a process with name "file-watcher [2]" was the culprit. Killing it mitigated the issue, but I don't know if there are any consequences (and it's a bit annoying having to do that).
I've recently experienced the same issue with Bruno, which also uses Electron. In that case I was able to find out a repro, and it was related to deleting files that were being watched.
One detail, not sure if relevant, is that my workspace is on a Windows Dev Drive.
VS Code version: Code 1.112.0 (07ff9d6, 2026-03-17T18:09:23Z)
OS version: Windows_NT x64 10.0.26200
Modes:
System Info
| Item | Value |
|---|---|
| CPUs | AMD Ryzen 9 7950X3D 16-Core Processor (32 x 4200) |
| GPU Status | 2d_canvas: enabled GPU0: VENDOR= 0x10de, DEVICE=0x2684 [NVIDIA GeForce RTX 4090], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=32.0.15.9579 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.7309 Machine model name: Machine model version: direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off |
| Load (avg) | undefined |
| Memory (System) | 63.65GB (32.05GB free) |
| Process Argv | --crash-reporter-id cc8b9d66-7842-4027-90bf-7ad186ce0e0e |
| Screen Reader | no |
| VM | 0% |
Extensions (17)
| Extension | Author (truncated) | Version |
|---|---|---|
| dart-code | Dar | 3.130.1 |
| flutter | Dar | 3.130.0 |
| docker | doc | 0.18.0 |
| copilot-chat | Git | 0.40.1 |
| arb-editor | Goo | 0.2.2 |
| theme-monokai-pro-vscode | mon | 2.0.12 |
| vscode-containers | ms- | 2.4.1 |
| vscode-docker | ms- | 2.0.0 |
| csdevkit | ms- | 2.10.3 |
| csharp | ms- | 2.120.3 |
| vscode-dotnet-runtime | ms- | 3.0.0 |
| vscode-pgsql | ms- | 1.18.2 |
| remote-containers | ms- | 0.447.0 |
| remote-wsl | ms- | 0.104.3 |
| powershell | ms- | 2025.4.0 |
| vsliveshare | ms- | 1.0.5959 |
| vscode-yaml | red | 1.21.0 |
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