macOS: Too many open files under normal session usage #583

Summary

I'm hitting intermittent Too many open files errors in Codex Monitor on macOS.

This does not look like just a random local spike. Codex Monitor's normal workload seems to keep a meaningful number of file descriptors open across:

• codex-monitor
• child codex app-server
• WebKit.WebContent

On my machine the soft limit is low:

ulimit -n
256

launchctl limit maxfiles
maxfiles    256 unlimited

With 5 workspaces configured, I sampled a live session and saw roughly:

• codex-monitor: ~104-105 FDs
• codex app-server: ~94-95 FDs
• WebKit.WebContent: ~59 FDs

I did not prove a monotonic FD leak in a short sample, so this may be more of a headroom / scaling issue under normal session management than a continuously growing leak.

Closing idle sessions or workspaces may reduce pressure temporarily, but because session management is the core job of the app, I think normal or mostly-idle usage should stay well below the point where Too many open files is possible.

Version: 0.7.66

There also wasn't much useful local logging to show which process actually crosses the limit. If useful, I can provide lsof snapshots and a longer sampling run.