FileSystemWatcher not working on remote machine

[bzy-debug]

Type: Bug

1. package https://github.com/microsoft/vscode-extension-samples/tree/main/lsp-sample extension
2. connect to a remote ssh machine through Remote - SSH extension
3. install the extension packaged from step 1 on remote vscode
4. add "languageServerExample.trace.server": "verbose" setting to remote vscode settings
5. create a .txt file to activate the installed lsp-sample extension, and open Language Server Example channel on output.
6. create a file named .clientrc, this is marked as watched files in the lsp-sample extension
7. see that there is no didChangeWatchedFiles notification from client to server in the channel opend on step 5.

VS Code version: Code 1.100.2 (Universal) (848b80a, 2025-05-14T21:47:40.416Z)
OS version: Darwin arm64 24.5.0
Modes: Unsupported
Remote OS version: Linux x64 5.15.0-97-generic

System Info

Item	Value
CPUs	Apple M3 Max (16 x 2400)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on 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 video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	2, 2, 3
Memory (System)	128.00GB (59.96GB free)
Process Argv	--new-window --crash-reporter-id 49131e3e-7370-46e1-a7b2-f54f9b7d20d4
Screen Reader	no
VM	0%

Item	Value
Remote	SSH: ci0-linux2
OS	Linux x64 5.15.0-97-generic
CPUs	Intel(R) Xeon(R) Gold 6348 CPU @ 2.60GHz (112 x 3113)
Memory (System)	251.55GB (213.21GB free)
VM	0%

Extensions (5)

Extension	Author (truncated)	Version
remote-ssh	ms-	0.120.0
remote-ssh-edit	ms-	0.87.0
remote-explorer	ms-	0.5.0
vscode-language-pack-zh-hans	MS-	1.100.2025051409
lsp-sample	vsc	1.0.0

A/B Experiments

vsliv368cf:30146710
vspor879:30202332
vspor708:30202333
vspor363:30204092
vscod805cf:30301675
binariesv615:30325510
c4g48928:30535728
azure-dev_surveyone:30548225
2i9eh265:30646982
962ge761:30959799
h48ei257:31000450
pythontbext0:30879054
cppperfnew:31000557
dwnewjupytercf:31046870
pythonrstrctxt:31112756
nativeloc2:31192216
5fd0e150:31155592
dwcopilot:31170013
6074i472:31201624
dwoutputs:31242946
customenabled:31248079
9064b325:31222308
copilot_t_ci:31222730
e5gg6876:31282496
pythoneinst12:31285622
bgtreat:31268568
4gafe986:31271826
c7cif404:31314491
996jf627:31283433
pythonrdcb7cf:31303019
usemplatestapi:31297334
0aa6g176:31307128
7bj51361:31289155
jjjhb125:31275178
pylancecolor:31314202
aj953862:31281341
generatesymbolt:31295002
convertfstringf:31295003
gendocf:31295004
xtab274-41mini:31318792

[vs-code-engineering]

Thanks for creating this issue! It looks like you may be using an old version of VS Code, the latest stable release is 1.100.3. Please try upgrading to the latest version and checking whether this issue remains.

Happy Coding!

[dbaeumer]

I tested this with a native app under WSL and I don't receive any file events either.

[dbaeumer]

repro.zip

[bpasero]

This issue could originate from a problem with file watching. Let me explain how file watching works in VSCode first and then provide some details how to get more logging data from how file watching behaves in your case.

Synopsis
VSCode has different strategies for file watching depending on your workspace and setup:

• no folder opened: files in opened editors are watched via node.js fs.watch
• folder opened: folder is watched recursively for all changes via parcel, opened editors with files not within the folder are watched via node.js fs.watch

If you are connected to a remote (SSH, WSL, Docker), the file watcher will run within the target file system. As such, even though you maybe on Windows where VSCode runs, if the remote is Linux, the file watcher will run in the Linux environment.

Platforms
Depending on the platform you are on, file watching is differently implemented:

• macOS: using fsevents services
• Windows: using ReadDirectoryChangesW method
• Linux: using inotify

Specifically on Linux, watching a large folder recursively can result in VSCode consuming too many file handles. If that is the case, you will see a warning notification with instructions how to solve that.

Limitations
File watching comes with a set of limitations:

• symbolic links are not followed automatically but you can explicitly add symbolic links to be watched via the files.watcherInclude setting
• mapped network drives or third party file system drivers are not guaranteed to produce file events
• in general, the operating system may decide to drop file events at any time, there is no 100% guarantee

Settings
Please review your settings to see if maybe a folder is excluded by accident. Specifically, the files.watcherExclude setting is relevant.

Logging (local)
!!! This is ONLY when you open a local workspace, for remote see below !!!
We provide logging for file events when you enable verbose logging. Steps are:

• open VSCode on the local workspace that shows the issue
• select View | Command Palette...
• select Developer - Set Log Level...
• pick Trace
• select View | Output
• select File Watcher from the dropdown on the right
• attach the output when doing the operation that exhibits the issue

Logging (remote)
!!! This is ONLY when you open a remote workspace (WSL, Docker, SSH), for local see above !!!
We provide logging for file events when you enable verbose logging. Steps are:

• open VSCode on the remote workspace that shows the issue
• select View | Command Palette...
• select Developer - Set Log Level...
• pick Trace
• select View | Output
• select Server from the dropdown
• attach the output when doing the operation that exhibits the issue

[dbaeumer]

Following the steps I see this

2025-06-05 14:09:39.991 [trace] [File Watcher (node.js)] [raw] ["change"] test.txt
2025-06-05 14:09:39.991 [trace] [File Watcher (node.js)] [CHANGED] /home/dirkb/Projects/mseng/VSCode/Playgrounds/text/test.txt
2025-06-05 14:09:39.992 [trace] [File Watcher (node.js)]  >> ignored (not included) /home/dirkb/Projects/mseng/VSCode/Playgrounds/text/test.txt
2025-06-05 14:09:39.992 [trace] [File Watcher (node.js)] [raw] ["change"] test.txt
2025-06-05 14:09:39.992 [trace] [File Watcher (node.js)] [CHANGED] /home/dirkb/Projects/mseng/VSCode/Playgrounds/text/test.txt
2025-06-05 14:09:39.992 [trace] [File Watcher (node.js)]  >> ignored (not included) /home/dirkb/Projects/mseng/VSCode/Playgrounds/text/test.txt