Tailscale daemon CPU usage spikes to 25-60% with high network utilization on Windows Server

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performanceUpdated Jul 6, 2025(via Exa)

Sources

Tailscale CPU usage spikes and stays at 25%+ (4c/4t) · Issue #16475github.com

Technologies:

Tailscalesubject

How to detect:

Tailscale Windows service (tailscaled.exe) CPU usage spikes to 25-30% (up to 60%) after a couple of minutes and remains elevated indefinitely. Network utilization reaches nearly 800 Mbps. Occurs on Windows Server 2019 with Hyper-V role. Issue persists after disabling subnets, DNS settings, antivirus, firewall rules, and reinstalling.

Recommended action:

Temporary workaround: disable 'Allow Incoming Connections' setting (limits functionality). Investigate potential interaction with subnet router on Linux VM running on same host via Hyper-V virtual switch bound to same network adapter. Check for routing loops or broadcast storms between Windows host and Linux VM subnet advertisement. Review bug report BUG-ced4a4e1f828ac2c8aa311fb3fd431cea4febba2a7e380e51770118c2e0e402e-20250706162921Z-1cda7fa65a85c5bc for details.