When using Codex to generate or modify code across a large number of files, the entire application becomes extremely slow and laggy. After Codex creates or edits many files within the same session, the UI responsiveness drops significantly. Simple actions such as scrolling, switching files, typing,…

Hey Jal! It sounds like you’re using a single session until the context window fills up, which then requires reoccurring compaction. Have you considered starting a new chat session once the context reaches around 70% capacity? This can help you avoid wasting tokens on compaction, reduce the risk o…

The problem is that even after starting a new conversation, the application is still very laggy. It feels like some resources may not be properly released. I suggest adding a mechanism so that the scrollbar does not need to load everything at once. Instead, users could click a “Load more” option to…

[image] Jal: It feels like some resources may not be properly released. Lag during long AI sessions is not always caused by a single process. On my Windows system, it is common for an AI tool to leave one or more long-running processes active after they should have been terminated. When this …

No, all of this comes from the Codex application itself. It is most likely related to Electron, so the layout and rendering within Electron may not be well optimized. To be honest, I would suggest switching the Windows version of Codex to WinUI instead. That would significantly improve performance …

You should check if this issue has been reported and if it is not a duplicate open a new issue. [image] openai/codex Lightweight coding agent that runs in your terminal - openai/codex

Same here. I noticed the codex app on my Mac runs very slowly, only ~1/10 of the speed as the cursor or claude code. Not sure why. I do have 73% rate limits remaining.

performance was good on my MAC a few days ago. Something was changed for sure in one of the updates and caused these problems. Codex APP performance is no longer ACCEPTABLE.

Same issue here, running up to date desktop codex app on mac (macos 26.3.1), and since a few days codex is extremely slow UI wise. Checking the cpu/ram usage is low and a lot of headroom on my device. Issue seems to come from the app itself.

Is there someone working on it and an estimation of when it will be fixed?

Same issue here. I suspect it’s caused by long sessions (at least in my case), but the problem persists if you open a brand new session

Codex becomes extremely slow and causes severe UI lag when working with many files

Codex

Adam_Forgac April 4, 2026, 4:32pm 18

Same issue here. I have tried like every single terminal/editor, but I am still unable to use it. Have you guys found some solution to this?

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Codex becomes extremely slow and causes severe UI lag when working with many files

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