From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 7BDD83CB37; Mon, 13 Nov 2023 15:41:28 -0500 (EST) Received: by mail-pg1-x52d.google.com with SMTP id 41be03b00d2f7-5bdbe2de25fso3848851a12.3; Mon, 13 Nov 2023 12:41:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1699908087; x=1700512887; darn=lists.bufferbloat.net; h=content-transfer-encoding:to:subject:message-id:date:from :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=Be9RLRON8WhCCPy+ga4NaU5OKYaO2dGsFwIsKuuwx4w=; b=MDCnksagnhqs7MssHXElOhUUVeL1vutb0z7cOJCybM6tasTKL5nmO2nYuVXGHVNnIN FJsorEtuT+1Nj++mqCF6O/JJqedRenpClFp3ALZpRvnZbqGIGHiHokOYpGPIpfE8oedX T7EfZcUdmRymvhKfo8ELnZrOy0QuNvFWQ9HDeG8UHXEQ6QfzAJYiA+ZDaWS6JtqetBEu eh4fe52dESLCAx5lEg3o7CjVIKVgup0AT43s1XDb5Z0KfQPv8UjpV8Cg37TMPYDHF+8f tsT9B9mu/NgQeifVpWC4p+wuB2YEk4C53Vhpc+ywZBORuBmU6hcSrqLAV0WplbMS3Hsf DfZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699908087; x=1700512887; h=content-transfer-encoding:to:subject:message-id:date:from :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Be9RLRON8WhCCPy+ga4NaU5OKYaO2dGsFwIsKuuwx4w=; b=iUBDipy996dbZzjyn/t+jcdBcFrvJi8UU36A5epAA21GAOgwdZtBPSf0SDMk20ITNu nyTF6dYrjkYDICe4eBpcdt/KXqOL3uw6XosUmRYuvcKodKrF/HoNSWEtT8eh+7oai7WK SjH4ZfQiu/6dZJVh6Vwcdro1QR8i3ZdgiOgo0eFyRrL0oovPSkUqgM1nKa6xPGnzRuHY 1kORbxJLAUZ4FdHF2ANLGqJyYo1iyY2/Mq1NcdclKs7fR9qpfup3wavSa2APxKTE8Jht M1x3iI3auUcddwuz/Uvt2cpo37H523dl7OjGNWWPf0UiLP19wXFPXkWwvVMiDitvGDuQ tOsw== X-Gm-Message-State: AOJu0YwrkfkSl2haUZefbyYZ201gQNr5E5xMq8d5pwJvLv4s9R1LlNKJ 4vmXhvQqP2XJlhTeu9SH57KVpjnrxwJgJ0T7OcjtsJBXEzA= X-Google-Smtp-Source: AGHT+IHp+cKgYLhf2+ajW3zvlHOSQEExU766Cf+bfKT//DGgGvKvFWoxadbsNVXvlOr8IHaxwbjvINPb+WQ764bWM8o= X-Received: by 2002:a17:90b:1d06:b0:280:2823:6615 with SMTP id on6-20020a17090b1d0600b0028028236615mr7383998pjb.36.1699908086945; Mon, 13 Nov 2023 12:41:26 -0800 (PST) MIME-Version: 1.0 From: Dave Taht Date: Mon, 13 Nov 2023 15:41:14 -0500 Message-ID: To: Dave Taht via Starlink , Make-Wifi-fast , =?UTF-8?Q?Network_Neutrality_is_back=21_Let=C2=B4s_make_the_technical_aspect?= =?UTF-8?Q?s_heard_this_time=21?= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Starlink] "Hunting Heisenbugs" talk Nov 14th 2:30 PM EST X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Nov 2023 20:41:28 -0000 Paul McKenney, inventor of Stochastic Fair Queueing (SFQ), inventor of RCU, solver of million year problems at IBM and now meta, and all around good speaker, is giving a talk on "Hunting Heisenbugs" 2:30PM EST Tuesday November 14th, 2023, at the Linux Plumbers conference. https://lpc.events/event/17/contributions/1504/ A heisenbug is a bug that when you instrument the code to find it, vanishes. See wikipedia for more details. I have spent many months, and years, even - trying to turn heisenbugs into "Bohrbugs". Bufferbloat was, originally, essentially a heisenbug, until Tom Herbert invented BQL. Every engineer has a few in their backlog that keeps them awake at night. I have 3 outstanding, the biggest: I have been trying (in my spare time) for nearly a year now, trying to find a bug in the mt76's mu-mimo stack that causes excessive retransmits and latency under circumstances I can rarely replicate, which is proving more elusive to find as the infamous fq-crypto bug we had had that stalled make-wifi-fast project out for 4 horrible months, and stumped dozens of people. It is similarly damaging for users of that chipset, when it happens. https://blog.cerowrt.org/post/crypto_fq_bug/ --=20 :( My old R&D campus is up for sale: https://tinyurl.com/yurtlab Dave T=C3=A4ht CSO, LibreQos