Codex Desktop ARM64 Windows idles at ~10% CPU in main process

What version of the Codex App are you using?

Codex Desktop 26.623.11225.0 ARM64

Codex CLI/runtime observed:

• codex-cli 0.142.3 from codex --version
• codex doctor reports Codex Doctor v0.142.5 · windows-aarch64, runtime version 0.142.5

What platform is your computer?

• Windows 11 IoT Enterprise ARM64
• OS version: 10.0.26200
• CPU: Snapdragon(R) X 10-core X1P64100 @ 3.40 GHz
• PowerShell process architecture: Arm64
• OS architecture: Arm64
• Codex.exe PE machine: ARM64
• git.exe PE machine: ARM64

What issue are you seeing?

Codex Desktop sits at approximately 10-11% CPU while idle on a Windows ARM64 / Snapdragon X machine. This appears to be roughly one core busy continuously.

After restart, with no active task visibly running, live CPU sampling showed the main Codex Desktop process as the hot process:

Kind              : main
ProcessName       : Codex
CurrentCpuPercent : 10.44
MemoryMB          : 255.5
CommandLine       : "C:\Program Files\WindowsApps\OpenAI.Codex_26.623.11225.0_arm64__2p2nqsd0c76g0\app\Codex.exe" codex://threads/new?path=...jobscripts

Other child processes were much lower in the same sample:

Kind              : gpu-process
CurrentCpuPercent : 1.03

Kind              : renderer
CurrentCpuPercent : 0.22

The app-server was not the source of the high CPU in the samples. Restarting Codex did not clear the idle loop. Restarting without the workspace deep link also did not clear it.

What steps can reproduce the bug?

1. Launch Codex Desktop on Windows ARM64.
2. Leave the app open with no task actively running.
3. Observe CPU usage in Task Manager.
4. Optionally sample live CPU over several seconds with PowerShell.
5. Restart Codex and observe the same sustained idle CPU.
6. Launch Codex without a workspace deep link and observe the same sustained idle CPU.

Expected behavior

When Codex Desktop is idle and no task is running, CPU usage should drop close to zero. The main Codex.exe process should not continuously consume about one core.

Actual behavior

The main Codex.exe process remains around 10-11% CPU while idle on a 10-core Snapdragon X system.

Diagnostics already performed

Confirmed this is not x64 emulation:

PROCESSOR_ARCHITECTURE=ARM64
ProcessArchitecture=Arm64
OSArchitecture=Arm64
codex.exe Machine=ARM64
git.exe Machine=ARM64

Confirmed the install looked healthy via codex doctor:

Codex Doctor v0.142.5 · windows-aarch64
17 ok · 1 idle · 1 notes · 0 warn · 0 fail ok

One oddity: codex update failed with a platform-detection error despite running on Windows ARM64:

install.ps1 supports Windows only. Use install.sh on macOS or Linux.

Related issues

There are existing high idle CPU reports for Codex Desktop, mostly macOS / renderer / GPU paths. This report is specifically for Windows ARM64 where the hot process appears to be the main Codex.exe process rather than the renderer or app-server.

Update: Confirmed that High Idle rate at 10% or more continously, even when Codex is idling as a background process (process in in tray and no active windows are running).