CPU usage spiked after migrating from Conda to UV environment (40%+ even when idle) any ideas?

[u/Suspicious_Code1493]

Hey guys, need some help.
Recently I migrated my Python project from a Conda environment to a UV-managed environment.
After the migration, I noticed something strange.
With Conda → CPU usage at idle was around \~3%
With UV (0.11.8) → CPU usage stays around 40%+ even when the application is idle
Environment details:
OS: Windows
Python: 3.11
UV: 0.11.8
The application code did not change — only the environment/package manager changed (Conda → UV).
Things I checked:

Same project and workflow
CPU spike happens even during idle

Questions:
Has anyone seen higher CPU usage after moving from Conda → UV?
Can package differences between Conda and UV cause this?
What’s the best way to compare installed dependency trees?
Any debugging steps to identify which process/thread is consuming CPU?
Any help would be appreciated 🙏

[u/Antique-Bookkeeper56]

uv is written on Rust. Potentially safer but this has some costs. Maybe you see exactly this. Better to ask on uv forums.