OpenBSD: PF queues break the 4 Gbps barrier
5 hours ago
- #OpenBSD
- #Networking
- #HFSC
- Internal 32-bit limitation in HFSC service curve structure capped bandwidth at ~4.29 Gbps.
- Modern network interfaces (10G, 25G, 100G) made this limitation problematic.
- Patch updates HFSC scheduler to use 64-bit integers, removing the bottleneck.
- Fixes display bug in pftop(1) for bandwidth values above 4 Gbps.
- PF queue bandwidth configuration now works correctly for high-speed interfaces.
- Supports values up to 999G, with no changes needed for existing sub-4G configurations.
- Patch and discussion available on tech@, ready for commit by March 20, 2026.