From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-xd2f.google.com (mail-io1-xd2f.google.com [IPv6:2607:f8b0:4864:20::d2f]) (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 157213CB37 for ; Tue, 30 Nov 2021 19:23:49 -0500 (EST) Received: by mail-io1-xd2f.google.com with SMTP id p65so4521199iof.3 for ; Tue, 30 Nov 2021 16:23:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=iqHbTJtdPxDPgliMmPRZN0U70YFEE7XWEejn8DdDX/Q=; b=n9lKbZx52fqX710bh2XGvG5Fy39zNwx/OSUPSKvAvrNEOIOWSHq/pg+EeU2VxUzhB2 DtD/kyIeYBhexKPYUG2VcIU/FUGwYT+xYIlXS0Sv4WXqk2gia/EW7kW+dW5EvxbyhIDx 8SKbShy1B8nv7m7KGriHNy3AoZREiohhHtMGoUA//lylSsH1DAdOvOVJHGJuZto9FiJ5 nx4+O0OI3Col0hk+Eu2x7ZMLRJ2Sn/cunL8ovcaJSxVZ4VstxJFnZlQM1RK1J+cTz50C eTUT7YRE6YF+V9/JzOPfd5mZxeX6wKt3R2+iCsdIPrnKJiE823f4kqPaz7WXfiYqQK7W ggug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=iqHbTJtdPxDPgliMmPRZN0U70YFEE7XWEejn8DdDX/Q=; b=CAC8jcdGoS4LbCwkcI6RDKuCH6ZmiVJhToYbO5FPxFuXmU043UHOGRWLZstaT6dDKx Kgyl1IYrf81n2xUMXlR0fy9JFEIUqj9qj1pVMfwrfC2X6a/THe9ACR62MgPG9xOJa3eE N3u2RDIMJsrlYXqpM8UvkbY0nrmGzvl/k884j46fe5Eo+mzwr0sp0KYmBtLyW0ZtuxR4 t46I6jZPEpCyffLC3wbg52ER7QUDxfW3kUncBSVPszZD51QuYTh7Ab+jLWj7G6vsoFnw TkdTTBpk5F5ddDolGmedfMduyJAWZ6i2G2IXUpCKcxLIdTR1rPjOl5J0hTVOXzkwUvV9 PAew== X-Gm-Message-State: AOAM530+/wntQAbb90NCsQWdi9YmKP86/sjXyvFosJmx5uKk1KyP47HS XCOPlh4Ervqg25XTMCWVN/wj2J+n2tzEpbUZUFW6Stsn X-Google-Smtp-Source: ABdhPJwphwOv8d0kIfLszY3WuMnNQCS5yvoHKAgOn6OmboNb654bSG9iJqDex4meMMBhl4Y9JBytCUJp7nUg+d0zznA= X-Received: by 2002:a02:ba8b:: with SMTP id g11mr4619436jao.128.1638318228294; Tue, 30 Nov 2021 16:23:48 -0800 (PST) MIME-Version: 1.0 References: <1638312755.776218387@apps.rackspace.com> In-Reply-To: <1638312755.776218387@apps.rackspace.com> From: Dave Taht Date: Tue, 30 Nov 2021 16:23:35 -0800 Message-ID: To: "David P. Reed" Cc: cerowrt-devel Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [Cerowrt-devel] risc-v options? X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Dec 2021 00:23:49 -0000 On Tue, Nov 30, 2021 at 2:52 PM David P. Reed wrote: > > For what? Because it's shiny. Because I don't care for the owner of softbank and arm very much. Because at least the core is open source, and I'd really like to try out some long held ideas about reducing context switch latency. And there's a couple instructions I'd like to add. >I have recently gotten a MicroSemi RISC-V SoC board with embedded FPGA (or= maybe it is better thought of as an FPGA board with multicore hard logic R= ISC-V host.) Runs Linux very fast. It's not set up to be a router, though -= not unless I populate its PCIe slot with NICs. Standard Linux drivers for= PCIe devices all work quite well, so far. how fast can it context switch? (irtt bench) I am impressed that it works with anything on pcie. I was mostly dismissing risc-v as a toy that could never catch up to arm 3 years ago, but with the enormous chinese investment in it... > > > These early 64 bit RISC-V implementations are pretty darn good, but unlik= e Intel's Xeons, they don't yet handle memory channel performance very well= . Intel has always had an advantage in on-chip cache. > > > > (The 32-bit RISC-V's are really competing with ARM based microcontrollers= for embedded systems. I don't find them interesting, though I have a coupl= e sample boards with 32 bit RISC-V cores). I don't find 32 bit risc-v interesting. I did fiddle with the 128 bit risc-v stuff for a while. > > > A random guess on my part: even consumer routers will be moving to 64-bit= processor designs in the next couple years. Many already have. > That's because the price difference is getting quite small, as a percenta= ge of total product cost, and because it is hard to buy "small memory addre= ss space" DIMMs. I could be wrong, but extrapolation from today's trends su= ggests that is more likely than not. 802.11ax standards require - no joke - a 2MByte buffer per station. > > > > > > On Friday, November 26, 2021 3:02pm, "Dave Taht" sa= id: > > > has anyone tried the latest generations of risc-v? > > > > https://linuxgizmos.com/17-sbc-runs-linux-on-allwinner-d1-risc-v-soc/ > > > > -- > > I tried to build a better future, a few times: > > https://wayforward.archive.org/?site=3Dhttps%3A%2F%2Fwww.icei.org > > > > Dave T=C3=A4ht CEO, TekLibre, LLC > > _______________________________________________ > > Cerowrt-devel mailing list > > Cerowrt-devel@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/cerowrt-devel > > --=20 I tried to build a better future, a few times: https://wayforward.archive.org/?site=3Dhttps%3A%2F%2Fwww.icei.org Dave T=C3=A4ht CEO, TekLibre, LLC