From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=0.2 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 Received: (qmail 24729 invoked from network); 7 Dec 2022 19:13:35 -0000 Received: from 9front.inri.net (168.235.81.73) by inbox.vuxu.org with ESMTPUTF8; 7 Dec 2022 19:13:35 -0000 Received: from mail-vs1-f42.google.com ([209.85.217.42]) by 9front; Wed Dec 7 14:12:26 -0500 2022 Received: by mail-vs1-f42.google.com with SMTP id f189so13675099vsc.11 for <9front@9front.org>; Wed, 07 Dec 2022 11:12:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=to:subject:message-id:date:from:references:in-reply-to:mime-version :from:to:cc:subject:date:message-id:reply-to; bh=l1x4ehIOGRXeD96WNuCdrD7gtKXVmQd8D35HjZ1n9KM=; b=eUY81Apn58WaXD3ZxsekQLvT7esVbY+PuEctXt66JCjBQ6BAU7ocqwo+hqWFO/kShX TgoRqJ2bvXuhfp/K1+RUMCegoAqfjqqMFQeXVHGCG6lNeKYDpTl/CcMAIIwNCEOMO75V NQf0SZOhQRO+bYlSXMZd6N9RS6lQB3EKDOgln2RmYX12AfmagyyD23Um+g++11ReWvrI NbC0ks3v45aC0PcOajc7WDkW/EpvUy+sZtvj5h4YRvyUDQnG+IFpLGmtC/4TliVEfAvQ y3HiLHZuNGxSvrlzCxBWj/OiELoZx2shTv2q1DZ07fOY0212pLfHzLgfiuHAw//vL+MU CRew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:subject:message-id:date:from:references:in-reply-to:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=l1x4ehIOGRXeD96WNuCdrD7gtKXVmQd8D35HjZ1n9KM=; b=dPHYKxav18dll39hiCjN3cXRF9dz13U5iY94RJcYSQ48veT6rSP/qAq8k5rs6RSqsN P9iGcMbweBbfFTG9bC81z4GUqssfwxUHjnby/dQOxMZVHB+bEC8Z8UCZtAfmSasFhJHn K4xrmY7eLbyuxJoKHMhtS9Vj0wd+3wjC/SPs+YSuYLkM1EoU1nezo6AKl/JCHqN5ApTU 6FztDOXYg5GURUvK29fjxEXTR1bAufVjbLo4+1JT4L+LlrTbvxjabItXMG8LQltAWpu7 B55kEzMbC0BXy9JYgyoG90+qIz37MfEo6oShhGcMiTFFennTUSnXlamh4vA/1Noq47If 9XfQ== X-Gm-Message-State: ANoB5pmhuzDe8CkZ40M+0uZvfAHnalP5hq4ksEPf2xl6KaZeOA/HrElE uVrWiIJW0aenAThhjfbU2zxWeFptrxbh/pc2NyJ5Q3GTvhg= X-Google-Smtp-Source: AA0mqf766WuRSeVlhhgmbaLVN5b6rjAqLoo7HOZ+oxE93DEikznKagBpGBjJYaJIwloh8rWDpY9WCWGhFoV7v+8dY4A= X-Received: by 2002:a67:e981:0:b0:3b0:6b23:1d95 with SMTP id b1-20020a67e981000000b003b06b231d95mr38700340vso.56.1670440343212; Wed, 07 Dec 2022 11:12:23 -0800 (PST) MIME-Version: 1.0 Received: by 2002:ab0:60d7:0:0:0:0:0 with HTTP; Wed, 7 Dec 2022 11:12:22 -0800 (PST) In-Reply-To: References: <632533984.161412.1668888549169@comcenter.netcologne.de> From: hiro <23hiro@gmail.com> Date: Wed, 7 Dec 2022 20:12:22 +0100 Message-ID: To: 9front@9front.org Content-Type: text/plain; charset="UTF-8" List-ID: <9front.9front.org> List-Help: X-Glyph: ➈ X-Bullshit: virtual private property hosting-aware strategy-oriented backend Subject: Re: [9front] [patch] ethervgbe: add rx checksum offloading Reply-To: 9front@9front.org Precedence: bulk this netflix guy mentions some important points: https://www.youtube.com/watch?v=36qZYL5RlgY e.g. if they don't enable *all* those optimizations there's barely any benefit. turn one off and performance degrades miserably. basically you have to use TCP segmentation offload, TCP large receive offload, some kind of sendfile() thingy, and other stuff that i don't understand, all in unison, or you basically get nothing at all out of it. for us i think it's best we just skip all this badly designed over-complexity. On 11/20/22, hiro <23hiro@gmail.com> wrote: > my hunch is also that checksum offloading is not worth it, since we > don't have any kind of fastpath in our packet forwarding (we memcpy > every packet). > > also, if we did more computationally intensive work on the packet > data, like aes encryption, i understand why somebody might want to use > accelerators for that part. but those checksums are dirt-cheap, on any > CPU. > > On 11/19/22, ori@eigenstate.org wrote: >> Quoth Arne Meyer : >>> Is hw offloading something we want? I ask because I think there is >>> something wrong with ether8169 offloading and I'm working on a patch to >>> fix or axe this. >>> >> >> if it makes a real difference in performance and isn't too complex, it >> may >> be worth it, but I suspect software is more than fast enough for >> most of the cards we support. >> >> >