Re: [LKP] [tcp] a337531b94: netperf.Throughput_Mbps -6.1% regression

From: Eric Dumazet
Date: Tue Oct 09 2018 - 22:05:35 EST


On Tue, Oct 9, 2018 at 7:01 PM kernel test robot <rong.a.chen@xxxxxxxxx> wrote:
>
> Greeting,
>
> FYI, we noticed a -6.1% regression of netperf.Throughput_Mbps due to commit:
>
>
> commit: a337531b942bd8a03e7052444d7e36972aac2d92 ("tcp: up initial rmem to 128KB and SYN rwin to around 64KB")
> https://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git master
>
> in testcase: netperf
> on test machine: 16 threads Intel(R) Xeon(R) CPU D-1541 @ 2.10GHz with 8G memory
> with following parameters:
>
> ip: ipv4
> runtime: 900s
> nr_threads: 200%
> cluster: cs-localhost
> test: TCP_STREAM
> ucode: 0x7000013
> cpufreq_governor: performance
>
> test-description: Netperf is a benchmark that can be use to measure various aspect of networking performance.
> test-url: http://www.netperf.org/netperf/
>
>

This should have been fixed by :

041a14d2671573611ffd6412bc16e2f64469f7fb tcp: start receiver buffer
autotuning sooner