UI freezes indefinitely when patching large Python files in large projects

[JayZenith]

Description

Opencode hangs on "Preparing patch..." indefinitely when editing large Python files inside large projects (reproduced with server_args.py ~255KB in the sglang repo).

pyright cold-starts and scans the entire project on every session, running at 100+ CPU. During that scan it stops draining its stdin socket. textDocument/didOpen sends the full file -- at 255KB this overflows the ~213KB kernel socket buffer. Both sides stall. No timeout, no recovery.

Confirmed with ss -xp: Recv-Q 219KB, Send-Q 224KB simultaneously. Doesn't reproduce when the file is isolated -- no pyproject.toml means no project scan, pyright drains the socket instantly.

Plugins

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OpenCode version

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Steps to reproduce

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Screenshot and/or share link

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Operating System

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Terminal

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[github-actions]

This issue might be a duplicate of existing issues. Please check:

• bug: apply_patch waits for LSPs sequentially causing big multi-file patches to hang #10965: Also involves apply_patch hanging due to LSP.touchFile blocking — same code path, though that issue focuses on sequential waiting while this one identifies the underlying pipe buffer overflow mechanism
• [Bug] LSP freezes and diagnostics timeout too short (3s) for heavy language servers #13328: Covers LSP freezes and insufficient timeouts for heavy language servers more broadly

If your issue is distinct (specifically the pipe buffer fill / blocked write scenario), it would help to add your OpenCode version and OS details to distinguish it from the above.

[h4rvey-g]

Same issue. One temp workaround is to ask agent to "retry editing in smaller patches"

[AlejandroBaron]

I get the same issue, disabling LSP servers worked for me, both pyright and pylance show this problem