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Message-ID: <63039789-839c-865e-27b3-1f843c87de9b@linux.ibm.com>
Date:   Mon, 16 May 2022 18:58:20 +0200
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Subject: Re: [PATCH net-next v3 0/2] net/smc: send and write inline
 optimization for smc
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To:     Guangguan Wang <guangguan.wang@linux.alibaba.com>,
        davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, leon@kernel.org, tonylu@linux.alibaba.com
Cc:     linux-s390@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220516055137.51873-1-guangguan.wang@linux.alibaba.com>
From:   Karsten Graul <kgraul@linux.ibm.com>
Organization: IBM Deutschland Research & Development GmbH
In-Reply-To: <20220516055137.51873-1-guangguan.wang@linux.alibaba.com>
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On 16/05/2022 07:51, Guangguan Wang wrote:
> Send cdc msgs and write data inline if qp has sufficent inline
> space, helps latency reducing. 
> 
> In my test environment, which are 2 VMs running on the same
> physical host and whose NICs(ConnectX-4Lx) are working on
> SR-IOV mode, qperf shows 0.4us-1.3us improvement in latency.
> 
> Test command:
> server: smc_run taskset -c 1 qperf
> client: smc_run taskset -c 1 qperf <server ip> -oo \
> 		msg_size:1:2K:*2 -t 30 -vu tcp_lat
> 
> The results shown below:
> msgsize     before       after
> 1B          11.9 us      10.6 us (-1.3 us)
> 2B          11.7 us      10.7 us (-1.0 us)
> 4B          11.7 us      10.7 us (-1.0 us)
> 8B          11.6 us      10.6 us (-1.0 us)
> 16B         11.7 us      10.7 us (-1.0 us)
> 32B         11.7 us      10.6 us (-1.1 us)
> 64B         11.7 us      11.2 us (-0.5 us)
> 128B        11.6 us      11.2 us (-0.4 us)
> 256B        11.8 us      11.2 us (-0.6 us)
> 512B        11.8 us      11.3 us (-0.5 us)
> 1KB         11.9 us      11.5 us (-0.4 us)
> 2KB         12.1 us      11.5 us (-0.6 us)
> 
> Guangguan Wang (2):
>   net/smc: send cdc msg inline if qp has sufficient inline space
>   net/smc: rdma write inline if qp has sufficient inline space
> 
>  net/smc/smc_ib.c |  1 +
>  net/smc/smc_tx.c | 17 ++++++++++++-----
>  net/smc/smc_wr.c |  5 ++++-
>  3 files changed, 17 insertions(+), 6 deletions(-)
> 

I like that change, thank you!

For the series:

Acked-by: Karsten Graul <kgraul@linux.ibm.com>