hkall

Good to hear that it helped, thanks for the comprehensive feedback.

It should have less impact on latency than traditional hardware IRQ coalescing. However I can't quantify it. Few more details you can find in original_commit_message

The performance difference at 2.5Gbps may be caused by the fact that r8169 doesn't support RSS. All load is on one CPU. Background is that Realtek doesn't provide any data sheets. You may be able to improve the performance by using packet coalescing at GRO level by using the following settings. You can play with the values. Feedback whether this improves the performance would be appreciated. echo 20000 > /sys/class/net/<if>/gro_flush_timeout echo 10 > /sys/class/net/<if>/napi_defer_hard_irqs

Performance decrease seems to be in the rx direction. r8169 per default has interrupt coalescing disabled what may contribute to this. You can enable it via ethtool or even better check the following: echo 20000 > /sys/class/net/<if>/gro_flush_timeout echo 1 > /sys/class/net/<if>/napi_defer_hard_irqs