On 10/9/24 9:49 AM, Pavel Begunkov wrote: > On 10/9/24 16:43, Jens Axboe wrote: >> On 10/9/24 9:38 AM, David Ahern wrote: >>> On 10/9/24 9:27 AM, Jens Axboe wrote: >>>> On 10/7/24 4:15 PM, David Wei wrote: >>>>> =========== >>>>> Performance >>>>> =========== >>>>> >>>>> Test setup: >>>>> * AMD EPYC 9454 >>>>> * Broadcom BCM957508 200G >>>>> * Kernel v6.11 base [2] >>>>> * liburing fork [3] >>>>> * kperf fork [4] >>>>> * 4K MTU >>>>> * Single TCP flow >>>>> >>>>> With application thread + net rx softirq pinned to _different_ cores: >>>>> >>>>> epoll >>>>> 82.2 Gbps >>>>> >>>>> io_uring >>>>> 116.2 Gbps (+41%) >>>>> >>>>> Pinned to _same_ core: >>>>> >>>>> epoll >>>>> 62.6 Gbps >>>>> >>>>> io_uring >>>>> 80.9 Gbps (+29%) >>>> >>>> I'll review the io_uring bits in detail, but I did take a quick look and >>>> overall it looks really nice. >>>> >>>> I decided to give this a spin, as I noticed that Broadcom now has a >>>> 230.x firmware release out that supports this. Hence no dependencies on >>>> that anymore, outside of some pain getting the fw updated. Here are my >>>> test setup details: >>>> >>>> Receiver: >>>> AMD EPYC 9754 (recei >>>> Broadcom P2100G >>>> -git + this series + the bnxt series referenced >>>> >>>> Sender: >>>> Intel(R) Xeon(R) Platinum 8458P >>>> Broadcom P2100G >>>> -git >>>> >>>> Test: >>>> kperf with David's patches to support io_uring zc. Eg single flow TCP, >>>> just testing bandwidth. A single cpu/thread being used on both the >>>> receiver and sender side. >>>> >>>> non-zc >>>> 60.9 Gbps >>>> >>>> io_uring + zc >>>> 97.1 Gbps >>> >>> so line rate? Did you look at whether there is cpu to spare? meaning it >>> will report higher speeds with a 200G setup? >> >> Yep basically line rate, I get 97-98Gbps. I originally used a slower box >> as the sender, but then you're capped on the non-zc sender being too >> slow. The intel box does better, but it's still basically maxing out the >> sender at this point. So yeah, with a faster (or more efficient sender), >> I have no doubts this will go much higher per thread, if the link bw was >> there. When I looked at CPU usage for the receiver, the thread itself is >> using ~30% CPU. And then there's some softirq/irq time outside of that, >> but that should ammortize with higher bps rates too I'd expect. >> >> My nic does have 2 100G ports, so might warrant a bit more testing... > If you haven't done it already, I'd also pin softirq processing to > the same CPU as the app so we measure the full stack. kperf has an > option IIRC. I thought that was the default if you didn't give it a cpu-off option? I'll check... -- Jens Axboe
