High CPU usage and overheating on macOS when Codex is active in Antigravity, even with an empty project
What version of the IDE extension are you using?
26.409.20454
What subscription do you have?
ChatGPT Plus
Which IDE are you using?
Google Antigravity
What platform is your computer?
Darwin 25.3.0 arm64 arm
What issue are you seeing?
When Codex is active inside Antigravity on macOS, CPU usage becomes abnormally high and my MacBook heats up significantly.
I tested this multiple times with Activity Monitor and isolated the issue as much as possible. The abnormal load appears when Codex is enabled in Antigravity. In the problematic state, Activity Monitor shows very high CPU usage from these processes:
Antigravity Helper (Renderer)
Antigravity Helper (Plugin)
In some cases I observed values like:
Antigravity Helper (Renderer): 285%+
Antigravity Helper (Renderer): 100%+
Antigravity Helper (Plugin): 50%+
When this happens, the machine gets noticeably hot.
I also tested with an empty project folder, and the issue still occurs there, so this does not seem to depend on project size.
What steps can reproduce the bug?
- Open Antigravity on macOS.
- Enable the Codex extension/plugin.
- Open a project folder in Antigravity.
- Wait briefly and check Activity Monitor.
- Observe very high CPU usage from Antigravity Helper (Renderer) and Antigravity Helper (Plugin).
I also tested these comparison cases:
- Antigravity closed -> no overheating, no abnormal CPU
- Antigravity open, no project open, Codex disabled -> normal
- Antigravity open, no project open, Codex enabled -> normal
- Antigravity open, project open, Codex disabled -> normal
- Antigravity open, project open, Codex enabled -> high CPU and overheating
- Antigravity open, empty project folder open, Codex enabled -> high CPU and overheating again
This suggests the problem is specifically triggered when Codex is active in Antigravity, even if the opened folder is empty.
What is the expected behavior?
CPU usage should remain near idle when no heavy task is running.
Enabling Codex should not cause Antigravity Helper (Renderer) and Plugin processes to consume excessive CPU, especially when the opened folder is empty or when no meaningful task is running.
The app should stay thermally normal during idle or light use.
Additional information
I downgraded the Codex extension to a previous version, but the problem remained.
This does not seem to be caused by Antigravity alone, because CPU stays normal when Codex is disabled.
This does not seem to be caused by project size alone, because the issue also happens with an empty folder.
Based on Activity Monitor, the issue appears related to Antigravity Helper (Renderer) / Plugin behavior when Codex is active.
7 Comments
Potential duplicates detected. Please review them and close your issue if it is a duplicate.
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Thanks, I reviewed the suggested potential duplicates.
My case seems especially close to #17394.
I can reproduce the high CPU issue when Codex is active even in an empty folder, and the load appears in renderer/plugin helper processes while the app is otherwise idle.
In my setup this happens inside Antigravity rather than plain VS Code, but the pattern looks very similar to the non-git workspace / renderer high CPU behavior described there.
I also tested:
This may be related to the same underlying issue as #17394, possibly around workspace/git-state handling or a renderer/webview loop.
I reviewed the suggested duplicates and after further testing, this now appears to be a duplicate of #17394.
My results matched the same pattern:
git init-> CPU returns to normalUpdate: I found that
git initonly fixes one part of the problem.I confirmed that:
git init-> CPU returns to normalHowever, after that, I ran a Codex agent task that created/modified files, and high CPU usage came back again even though the workspace was still a valid git repository (
git rev-parse --is-inside-work-treereturnedtrue).So there seem to be at least two triggers in my setup:
Downgrade Codex to v.26.325.21211 or lower - it resolved the same issue on Linux (the issue was both in VS Code and Antigravity)
https://github.com/openai/codex/issues/16231#issuecomment-4244762139
I am using openai.chatgpt-26.318.11754-darwin-arm64.vsix and still have this problem
<img width="313" height="52" alt="Image" src="https://github.com/user-attachments/assets/a99ae4be-233c-442e-8aa9-d850d83088c6" />
Fix for macOS arm64 https://github.com/openai/codex/issues/16231#issuecomment-4205506808