Linux 7.4 Networking: NIC Pacing Offload and Up to 70% Faster Mixed BIG TCP

The networking pull for the Linux 7.4 merge window landed, and there’s good stuff for anyone pushing packets.

Core

• Hardware pacing offload: a new pacing_offload device attribute lets the NIC handle timing and spacing of outgoing packets. Intel’s IDPF driver is first to support it.
• Up to 70% more throughput on mixed BIG TCP and non-BIG TCP paths, plus TCP/IP cache and contention work.
• Wi-Fi latency improvements and more Wi-Fi Aware and Wi-Fi 8 work.

Drivers

New Nebula Matrix NIX and Meta’s second-gen MPNIC drivers, Qualcomm IPQ5424 PPE support, more STMMAC platforms, new Realtek PHYs, and RTW88 now handles the RTL8723BS so the old staging driver can go. Bluetooth adds MediaTek MT7928 and Qualcomm QCC2072.

Also merged: F2FS gets a dedicated metadata cache and opt-in multi-grain timestamps, which ext4, Btrfs and XFS already have.

My take

Pacing offload is a network engineer’s kind of feature. Less CPU jitter, smoother egress. I’ll want to see real numbers once 7.4 ships.

God Bless, and Use the Source!

References & Further Reading

• Linux 7.4 Networking Brings Hardware Pacing Offload, New Drivers & More Performance (Phoronix)
• F2FS Adds Opt-In Multi-Grain Timestamps With Linux 7.4 (Phoronix)