> 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... it seems to me the only difference would be we will use the shared backlog_napi kthreads instead of having a dedicated kthread for each cpumap entry but we still need the napi poll logic. I can look into it if you prefer the shared kthread approach. @Jakub: what do you think? Regards, Lorenzo > > Thanks, > Olek >
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