Performance issues when there is a large amount of references to local modules

[Pidgegeddon]

Extension Version

v2.37.5

VS Code Version

Version: 1.105.1 (user setup)
Commit: 7d842fb85a0275a4a8e4d7e040d2625abbf7f084
Date: 2025-10-14T22:33:36.618Z
Electron: 37.6.0
ElectronBuildId: 12502201
Chromium: 138.0.7204.251
Node.js: 22.19.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.26200

Operating System

Windows 11 Pro Version 25H2 OS build 26200.6725

Terraform Version

Terraform v1.13.4 on windows_amd64

Behavior

Opening files and editing files in a folder with many terraform files and many module references causes vscode to hang. This is more noticeable with weaker cpu's or with more references to modules in multiple files. It looks like the extension is reading all module references in all files multiple times even when it is not needed.

I can see there have been multiple discussions on this, but they all seem stale? I apologize if this is a duplicate.

Steps to Reproduce

1. Have a couple of modules
2. Have a root module with many files and references to those modules.

I have created a repo demonstrating this issue that may be of use. That repo also contains a log file with the extension output.

• https://github.com/Pidgegeddon/tf-extension-slow-demo

Terraform Configuration

Project Structure

Gist

No response

Anything Else?

The demo repo "only" have 400 module references in 200 files. The folder/repo where we are experiencing more slowness have 519 module references in 199 files.

References

• Terrible format-on-save performance #1632
• Performance Improvement Plan #1557
• Avoid re-processing files on textDocument/didOpen if content is the same as on disk terraform-ls#1375
• Investigate optimisation opportunities for workspaces w/ symlinks terraform-ls#1398

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