Issue Station
Sign In
Tools hereToolbox

codex - 💡(How to fix) Fix Low cache hit rate when Codex integrates with GPT-5.5 [3 comments, 3 participants]

Official PRs (…)
ON THIS PAGE

Recommended Tools

×6

Utilities matched from this issue’s tags and category — try them while you read without losing context.

GitHub issue graph ai analysis

Paste a GitHub issue URL. We fetch that issue, discover linked issues from bodies/comments/timeline, collect linked pull requests, and produce a structured English report.

The report is written in English Markdown for sharing and archival.

Helpful · Quick feedback

Loading…
GitHub stats
openai/codex#20301•Fetched 2026-04-30 06:30:28
View on GitHub
Comments
3
Participants
3
Timeline
9
Reactions
0
Author
pyfdticpyfdtic
Participants
etraut-openaietraut-openaigithub-actions[bot]github-actions[bot]pyfdticpyfdtic
Timeline (top)
commented ×3labeled ×3closed ×1reopened ×1
RAW_BUFFERClick to expand / collapse

What version of Codex CLI is running?

0.125.0

Which model were you using?

gpt-5.5

What platform is your computer?

WSL2

What terminal emulator and version are you using (if applicable)?

Windows Terminal

What issue are you seeing?

When Codex integrates with the GPT-5.5 model, its cache hit rate is very low, which causes costs to be consumed rapidly.

In contrast, OpenCode integrated with GPT-5.5 has no such problem and maintains a high cache hit rate.

Besides, Codex paired with GPT-5.4 also achieves a high cache hit rate normally.

What steps can reproduce the bug?

We tested Codex integrated with GPT-5.4 and GPT-5.5 respectively. By checking the session logs of both versions, we can see there is a significant difference in the frequency of cached_input_tokens.

What is the expected behavior?

The expected behavior is that Codex with GPT-5.5 should maintain a normal high cache hit rate, consistent with the performance of Codex + GPT-5.4 and OpenCode + GPT-5.5, to avoid excessive and rapid cost consumption.

Additional information

No response

extent analysis

TL;DR

The issue may be resolved by investigating and adjusting the cache configuration or input token handling when using Codex with the GPT-5.5 model.

Guidance

  • Review the session logs to understand the difference in cached_input_tokens frequency between Codex integrated with GPT-5.4 and GPT-5.5.
  • Compare the cache hit rates of OpenCode with GPT-5.5 and Codex with GPT-5.4 to identify potential discrepancies in cache handling.
  • Investigate if there are any version-specific settings or optimizations in GPT-5.5 that could be affecting the cache performance.
  • Consider testing with a different version of the Codex CLI or GPT model to isolate the issue.

Example

No code snippet is provided as the issue does not contain sufficient code-related information.

Notes

The issue seems to be specific to the combination of Codex and GPT-5.5, and more information about the cache configuration and input token handling would be necessary to provide a definitive solution.

Recommendation

Apply workaround: Investigate and adjust the cache configuration or input token handling to improve the cache hit rate when using Codex with GPT-5.5, as the issue seems to be specific to this combination and not a general problem with the Codex CLI or GPT-5.5 model.

Vote matrix · Quick signals

Works
Did the solution work? Tap to confirm.
Easy Fix
Was it a quick fix?
Time Saver
Did it save you time?
Blocking
Was it severely blocking?
Common Issue
Are others likely hitting this too?
Flaky / Intermittent
Is it intermittent?
Verified / Reproducible
Can you reproduce it reliably?
Loading…
#api#GPU compatibility#latency issue#model loading#dependency error

Still need to ship something?

×6

Another batch ranked right after the header list — different links, same matching logic.

Back to top recommendations

TRENDING

codex - 💡(How to fix) Fix Low cache hit rate when Codex integrates with GPT-5.5 [3 comments, 3 participants]