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([2a0d:3344:2712:7e10:4d59:d956:544f:d65c]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-45b7e50e30asm146536405e9.24.2025.09.01.00.59.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 01 Sep 2025 00:59:16 -0700 (PDT) Message-ID: <5ef10a85-3b2a-468e-8a67-200c6ad63dfe@redhat.com> Date: Mon, 1 Sep 2025 09:59:15 +0200 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v15 03/15] net: homa: create shared Homa header files To: John Ousterhout Cc: "netdev@vger.kernel.org" , Eric Dumazet , Simon Horman , Jakub Kicinski References: <20250818205551.2082-1-ouster@cs.stanford.edu> <20250818205551.2082-4-ouster@cs.stanford.edu> <6d99c24c-a327-471b-964f-cfe02aef7ce2@redhat.com> Content-Language: en-US From: Paolo Abeni In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 8/29/25 7:08 PM, John Ousterhout wrote: > On Fri, Aug 29, 2025 at 12:53 AM Paolo Abeni wrote: >> If that is percent of total CPU time for a single core, such value is >> inconsistent with my benchmarking where a couple of timestamp() reads >> per aggregate packet are well below noise level. > > Homa is doing a lot more than a couple of timestamp() reads per > aggregate packet. Than it looks like this is the problem. Data processing should require ~ a single ts per packet. If you need more for instrumentation, you should likely put such code behind a compiler's conditional and enable them just in devel/debug build. Or even better you could use ftrace/bpf trace for that. /P