From: Daniel Xu <dxu@xxxxxxxxx> Date: Mon, 25 Nov 2024 16:56:49 -0600 > > > On Mon, Nov 25, 2024, at 9:12 AM, Alexander Lobakin wrote: >> From: Daniel Xu <dxu@xxxxxxxxx> >> Date: Fri, 22 Nov 2024 17:10:06 -0700 >> >>> Hi Olek, >>> >>> Here are the results. >>> >>> On Wed, Nov 13, 2024 at 03:39:13PM GMT, Daniel Xu wrote: >>>> >>>> >>>> On Tue, Nov 12, 2024, at 9:43 AM, Alexander Lobakin wrote: >> >> [...] >> >>> Baseline (again) >>> >>> Transactions Latency P50 (s) Latency P90 (s) Latency P99 (s) Throughput (Mbit/s) >>> Run 1 3169917 0.00007295 0.00007871 0.00009343 Run 1 21749.43 >>> Run 2 3228290 0.00007103 0.00007679 0.00009215 Run 2 21897.17 >>> Run 3 3226746 0.00007231 0.00007871 0.00009087 Run 3 21906.82 >>> Run 4 3191258 0.00007231 0.00007743 0.00009087 Run 4 21155.15 >>> Run 5 3235653 0.00007231 0.00007743 0.00008703 Run 5 21397.06 >>> Average 3210372.8 0.000072182 0.000077814 0.00009087 Average 21621.126 >>> >>> cpumap v2 Olek >>> >>> Transactions Latency P50 (s) Latency P90 (s) Latency P99 (s) Throughput (Mbit/s) >>> Run 1 3253651 0.00007167 0.00007807 0.00009343 Run 1 13497.57 >>> Run 2 3221492 0.00007231 0.00007743 0.00009087 Run 2 12115.53 >>> Run 3 3296453 0.00007039 0.00007807 0.00009087 Run 3 12323.38 >>> Run 4 3254460 0.00007167 0.00007807 0.00009087 Run 4 12901.88 >>> Run 5 3173327 0.00007295 0.00007871 0.00009215 Run 5 12593.22 >>> Average 3239876.6 0.000071798 0.00007807 0.000091638 Average 12686.316 >>> Delta 0.92% -0.53% 0.33% 0.85% -41.32% >>> >>> >>> It's very interesting that we see -40% tput w/ the patches. I went back >> >> Oh no, I messed up something =\ >> >> Could you please also test not the whole series, but patches 1-3 (up to >> "bpf:cpumap: switch to GRO...") and 1-4 (up to "bpf: cpumap: reuse skb >> array...")? Would be great to see whether this implementation works >> worse right from the start or I just broke something later on. > > Patches 1-3 reproduces the -40% tput numbers. Ok, thanks! Seems like using the hybrid approach (GRO, but on top of cpumap's kthreads instead of NAPI) really performs worse than switching cpumap to NAPI. > > With patches 1-4 the numbers get slightly worse (~1gbps lower) but it was noisy. Interesting, I was sure patch 4 optimizes stuff... Maybe I'll give up on it. > > tcp_rr results were unaffected. @ Jakub, Looks like I can't just use GRO without Lorenzo's conversion to NAPI, at least for now =\ I took a look on the backlog NAPI and it could be used, although we'd need a pointer in the backlog to the corresponding cpumap + also some synchronization point to make sure backlog NAPI won't access already destroyed cpumap. Maybe Lorenzo could take a look... Thanks, Olek
