Error running remote compact task: timeout waiting for child process to exit
Resolved 💬 5 comments Opened Apr 14, 2026 by seeb1337 Closed Apr 14, 2026
💡 Likely answer: A maintainer (github-actions[bot], contributor)
responded on this thread — see the highlighted reply below.
What version of Codex CLI is running?
0.120.0
What subscription do you have?
Pro
Which model were you using?
gpt-5.4
What platform is your computer?
Linux 6.17.0-20-generic x86_64 x86_64
What terminal emulator and version are you using (if applicable)?
Ghostty & t3code
What issue are you seeing?
Once thread is about to compact for its first time it gets errored. Can't run /compact, /feedback. Sometimes it goes through tho, but not very often.
<img width="1124" height="236" alt="Image" src="https://github.com/user-attachments/assets/8c95a8f8-e8f8-4b40-91cf-ac20d546eaab" />
What steps can reproduce the bug?
Fill the context to the top.
What is the expected behavior?
Compact.
Additional information
Codex said:
The failing turn shows a large Neon MCP doc fetch, not a ctx7 CLI/plugin call:
- The last big payload before compaction was server":"Neon","tool":"get_doc_resource" for docs/auth/production-checklist.md at /home/kox/.t3/userdata/logs/provider/aa59955c-ee49-4b6d-8a39-07ae0234c689.log:3006.
- Compaction started immediately after at /home/kox/.t3/userdata/logs/provider/aa59955c-ee49-4b6d-8a39-07ae0234c689.log:3007.
- Then Codex failed with compact_error=timeout waiting for child process to exit at /home/kox/.t3/userdata/logs/provider/aa59955c-
ee49-4b6d-8a39-07ae0234c689.log:3008.
So the mechanism is:
- Large tool output gets added to the thread’s model-visible history.
- Codex notices the thread is getting too large.
- Codex runs internal contextCompaction.
- That internal compaction worker times out.
5 Comments
Potential duplicates detected. Please review them and close your issue if it is a duplicate.
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Set a compact threshold 150k and now getting this @ 150k tokens..
Error running remote compact task: { "error": { "message": "Unknown parameter: 'prompt_cache_retention'.", "type": "invalid_request_error", "param": "prompt_cache_retention", "code": "unknown_parameter" } }
<img width="885" height="902" alt="Image" src="https://github.com/user-attachments/assets/a7f50136-6f46-4169-b0bb-01bbe8cd4bd2" />
FALLBACK: https://github.com/openai/codex/issues/17809#issuecomment-4246044036
We rolled back the change that caused this regression, so this should be addressed now. Apologies for the inconvenience.
@etraut-openai issue still exists for me.
<img width="1095" height="108" alt="Image" src="https://github.com/user-attachments/assets/8dbd5e50-ada7-4193-b7e6-f1b64729db56" />