Linux: cannot watch large folders (ENOSPC)

[isidorn]

• VSCode Version: c4b5142
• OS Version: Linux

Steps to Reproduce:

1. git clone https://github.com/Microsoft/TypeScript.git
2. you do not have to open any file, just wait a minute and notice multiple errors in developer console
3. I do not see this on OS X, only linux

Marking as important as I am not sure what does this potentially break. Extension host might be crashing.

[bpasero]

@isidorn this means the watcher is running out of handles, does the advise in http://code.visualstudio.com/Docs/supporting/faq#_linux-faq help?

[isidorn]

@bpasero that does not help, as my linux has that configured since forever

[bpasero]

@isidorn I think we are hitting the limits of what the OS can do...

[Tyriar]

@bpasero have you looked into Watchman by Facebook? That's what ember-cli uses.

[bpasero]

@Tyriar post GA I want to look into other options for watching on Mac/Linux. Though I believe if we change to adding watched folders one by one as needed by the UI, we can keep using chokidar. The expensive part in chokidar is watching large root folders recursively.

[Tyriar]

@bpasero I actually just ran into an ENOSPC when trying to build with gulp watch while running a single instance of code ~. That's an enormous amount of files/processing when only a tiny subset of the files are likely being worked on. Seems like a good route to follow.

[bpasero]

@Tyriar if you can find out any way to prevent this issue by increasing the file limit on Linux, we should update the existing entry at http://code.visualstudio.com/Docs/supporting/faq#_linux-faq

[Tyriar]

@bpasero Any reason the number is so small in the FAQ? It's apparently capable of much more http://stackoverflow.com/a/17437601/1156119

[bpasero]

@Tyriar good point! does it work with a higher number?

[Tyriar]

@bpasero yeah that fixes it. I'll update the docs, I'll also add how to load in the new config value without restarting.

[Tyriar]

Users should also be notified in a nicer way that this is how they increase the value. While we could do this set up as part of the .deb/.rpm packages, I would prefer to stay away from messing with global config files like that.

[bpasero]

@Tyriar nice, yes please update the docs. I think this is not a good situation to be in, so my suggested way forward is to reduce the number of file handles the watcher needs to install.

[Tyriar]

@bpasero 👍

Should you close this off (since it's solved by microsoft/vscode-docs#236) and make a new issue to explicitly stop watching entire directories trees when they're too large?

[bpasero]

I will leave this open and cleanup post GA, I have a bunch of watcher related issues for April.

[Tyriar]

Sounds good, I just put the docs PR up microsoft/vscode-docs#237.

[bpasero]

👍

[bpasero]

Will be addressed in #3998