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Date:   Tue, 28 Mar 2023 11:46:03 +0200
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Subject: Re: [PATCH net-next] net/core: add optional threading for backlog
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To:     Jakub Kicinski <kuba@kernel.org>
Cc:     netdev@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   Felix Fietkau <nbd@nbd.name>
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On 28.03.23 04:06, Jakub Kicinski wrote:
> On Sat, 25 Mar 2023 06:42:43 +0100 Felix Fietkau wrote:
>> >> In my tests it brings down latency (both avg and p99) considerably in
>> >> some cases. I posted some numbers here:
>> >> https://lore.kernel.org/netdev/e317d5bc-cc26-8b1b-ca4b-66b5328683c4@nbd.name/  
>> > 
>> > Could you provide the full configuration for this test?
>> > In non-threaded mode the RPS is enabled to spread over remaining
>> > 3 cores? 
>> 
>> In this test I'm using threaded NAPI and backlog_threaded without any 
>> fixed core assignment.
> 
> I was asking about the rps_threaded=0 side of the comparison.
> So you're saying on that side you were using threaded NAPI with
> no pinning and RPS across all cores?
Yes.

- Felix