Hi Mel, I did an experiment that you might find interesting. Using Brenden's early drop with eBPF in the mxl4 driver. I changed the mlx4 driver to use order-0 pages. It usually use order-3 pages to amortize the cost of calling the page allocator (which is problematic for other reasons, like memory pin-down, latency spikes and multi CPU scalability)
With this change I could do around 12Mpps (Mill packet per sec) drops, usually does 14.5Mpps (limited due to a HW setup/limit, with idle cycles). Looking at the perf report as a FlameGraph, the page allocator clearly show up as the bottleneck: http://people.netfilter.org/hawk/FlameGraph/flamegraph-mlx4-order0-pages-eBPF-XDP-drop.svg Signing off, heading for the plane soon... see you at MM-summit! -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer
