From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id bef1413a for ; Thu, 27 Jun 2019 14:59:14 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 0F5959BDE3; Fri, 28 Jun 2019 00:59:13 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id F0B069BD9B; Fri, 28 Jun 2019 00:58:37 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=bsdimp-com.20150623.gappssmtp.com header.i=@bsdimp-com.20150623.gappssmtp.com header.b="wYTDnoxI"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 2C9499BD9B; Fri, 28 Jun 2019 00:58:36 +1000 (AEST) Received: from mail-qt1-f182.google.com (mail-qt1-f182.google.com [209.85.160.182]) by minnie.tuhs.org (Postfix) with ESMTPS id 2D3FC9BD84 for ; Fri, 28 Jun 2019 00:58:35 +1000 (AEST) Received: by mail-qt1-f182.google.com with SMTP id i34so2746452qta.6 for ; Thu, 27 Jun 2019 07:58:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/vO5EB7BbaHNHy0rn2axnEXJkB3qTnsDSikpPhLtgpw=; b=wYTDnoxIxJm7sIPgR2H96gT8pAg0OlFFYUnAj0yi7p41sxFKj3s1oIy8TgmEcgWvMK zAJJxGwnE8q8jJdz7pdFrzXhiaZcuD1FUA3DurCsDRJ/gClwTPqDLyaWJtbW81XpojNH HG+Ik5ij9raeIbWlV6yDneMs5hmnD2FBbO04Avczl0Xp09y85AvbujVqfaztkuxKaZZi HaBsB71Au/gTdTH9mF92Z8xLW388jW7nUS6vbK/pXyRVErkRpmKk83Genn2LIb72w+kU rgqNS/5RZczrmz3/pHWBWd7qpPsk+zKau/a17vIr0BQd40R2B5kf6Uq5WAxvihvcPri2 MLIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/vO5EB7BbaHNHy0rn2axnEXJkB3qTnsDSikpPhLtgpw=; b=C3mjCcoAED+fMgqdgTAeq4iQwbMTiMWIm9k4nEwo2Rd5Aq/iC6DCCSS22ZjCpxcknY R2n3EyZRcbglZ4tprS4jemCRrWYUA/x205f19Zzw3z0wRiOJk/3J3PvHo97jz10oqeja /NZ6ZtLo47ymWPi2mtoT7yTRdfCgs8CcVMSVMgJWOQXWMP3p+TT+c9AMPCykb55+r4Va iOsumxrBvfnvegOT31Q5/sDGJ0y9tHjtP8M/n/ytUaHkxVl7nJRO/5th18LF33WesSeH EUFGNZ+zSKAAklKOe7EHn0sDPMT4ZBj7qAY8vxAejGFlnzuiaVfw+azmwrMJfKPRX7ES RZjw== X-Gm-Message-State: APjAAAXiZ4M0y6cGSxoLSvE39TggHDPUu3KU+EhC9Q2muH2fwGglOWRx iwWg7gQ2BxXPRFVBzxLfOVVXeVXu3Mj1ruIyfUyDwQ== X-Google-Smtp-Source: APXvYqyyl58av85rNqhmWgbn2Gpw6SxaaxmSXgxKQgEungq5xUvgI9vJMyvjNcfQPLLuuPrVvqBuRZGAWqp1dVLvy8M= X-Received: by 2002:a0c:d604:: with SMTP id c4mr3506927qvj.27.1561647514006; Thu, 27 Jun 2019 07:58:34 -0700 (PDT) MIME-Version: 1.0 References: <20190625000630.GA7655@mcvoy.com> <20190625003120.GA28608@mit.edu> <20190625004523.GB7655@mcvoy.com> <20190626024503.GA43970@wopr> <20190626025646.GR925@mcvoy.com> <20190626151143.GC3116@mit.edu> <20190626174431.GT925@mcvoy.com> <34DB62C2-7D8C-468B-99E1-CA035C9141A2@eschatologist.net> <04827B96-5B5E-473E-A95F-67C4292B69D1@cogs.com> <20190626202125.GA1206@mcvoy.com> <40c8b56dc61f5026@orthanc.ca> <8249B608-606A-4A32-8D56-D78F16BC217B@cogs.com> <201906271059.x5RAxZZ4020844@freefriends.org> <648F2E41-08C4-4A76-9AD0-D69F851EF0D7@cogs.com> In-Reply-To: <648F2E41-08C4-4A76-9AD0-D69F851EF0D7@cogs.com> From: Warner Losh Date: Thu, 27 Jun 2019 08:58:22 -0600 Message-ID: To: Ben Greenfield Content-Type: multipart/alternative; boundary="00000000000056568d058c4f6552" Subject: Re: [TUHS] CMU Mach sources? X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tuhs Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" --00000000000056568d058c4f6552 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Jun 27, 2019 at 5:13 AM Ben Greenfield via TUHS < tuhs@minnie.tuhs.org> wrote: > > > > On Jun 27, 2019, at 6:59 AM, arnold@skeeve.com wrote: > > > > Larry McVoy writes: > >>>> OK, I'll bite. Go read the source in the FreeBSD tree, which has > been > >>>> reduced in size by 60% according to someone on the team. Then come > >>>> back and draw me a picture of what it does. > > > > On Jun 27, 2019, at 12:01 AM, Lyndon Nerenberg > wrote: > >>> Larry, it seems to me your argument is the Mach code should never > >>> have been incorporated into BSD in the first place. That's fine, > >>> but it's not the Mach developers fault that happened, so maybe you > >>> should lay off them for not writing their research software to a > >>> production shop standard they were never a part of? > > > > Ben Greenfield via TUHS wrote: > >> My understanding is that the BSD layer was a requirement from DARPA. > >> DARPA wanted a =E2=80=9Cnormal=E2=80=9D interface to the kernel and BS= D was that > interface. > > > > Yes, Mach had to provide a BSD layer on top, but that's not the source > > of Larry's gripes. > > > > It's the other way around. 4.4 BSD pulled the VM code out of Mach and > > into BSD to provide mmap and some level of portability off the Vax. Fro= m > > there the Mach code got into FreeBSD. That's what Larry is complaining > > about and what Lyndon is saying isn't fair to the Mach guys. > > Thank you for this clarification, so this conversation has been going on > since the 80=E2=80=99s and gets ignited from time to time. > Yea, there's been three or four rounds of rototilling in the FreeBSD vm. While it shares some structures with its Mach ancestors, complaining about it to paint Mach as this or that is unfair. FreeBSD's sys/vm has had a crapton of changes to make to scale in an MP system, to adopt non-uniform page sizes, etc. Some of these changes have been done with skill and subtly. Some have been done by a ham-fisted goober. It would overstate things to say the most recognizable part of Mach is the copyright headers :), but those bits are arguable the most unchanged. What's resulted lacks architectural purity because it wasn't designed from scratch to be pure. It's grown organically over the last 30-odd years as different groups, companies and organizations have found it necessary to fund development. The SunOS 4.x code, which was almost donated to the BSD project only to be scuttled at the last minute, has the twin advantages of being purpose built for only two architectures and didn't need to scale to thousands of CPUs, and stopped evolving in the 90s. As such, it can maintain its architectural purity since it's not needed to grow and adapt since then. All that "growth" happened in Solaris. So it's also a bit unfair to compare that code which was developed over a decade to FreeBSD's. But yea, DARPA was about networking in the Unix world. BSD was Unix at the time since AT&T didn't have the business structure to do the contracts, and BSD's 2BSD or 3BSD was little more than a slightly more evolved V7 research edition with some really cool user land features and a few more drivers for hardware BSD users had. The Mach VM came late to the game and was never the focus of the DARPA contracts. For another view on how well CSRG integrated Mach into BSD, see NetBSD's uvm, a complete rewrite. Warner --00000000000056568d058c4f6552 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


=
On Thu, Jun 27, 2019 at 5:13 AM Ben G= reenfield via TUHS <tuhs@minnie.= tuhs.org> wrote:


> On Jun 27, 2019, at 6:59 AM, arnold@skeeve.com wrote:
>
> Larry McVoy writes:
>>>> OK, I'll bite.=C2=A0 Go read the source in the FreeBSD= tree, which has been
>>>> reduced in size by 60% according to someone on the team.= =C2=A0 Then come
>>>> back and draw me a picture of what it does.
>
> On Jun 27, 2019, at 12:01 AM, Lyndon Nerenberg <lyndon@orthanc.ca> wrote:
>>> Larry, it seems to me your argument is the Mach code should ne= ver
>>> have been incorporated into BSD in the first place.=C2=A0 That= 's fine,
>>> but it's not the Mach developers fault that happened, so m= aybe you
>>> should lay off them for not writing their research software to= a
>>> production shop standard they were never a part of?
>
> Ben Greenfield via TUHS <tuhs@minnie.tuhs.org> wrote:
>> My understanding is that the=C2=A0 BSD layer was a requirement fro= m DARPA.
>> DARPA wanted a =E2=80=9Cnormal=E2=80=9D interface to the kernel an= d BSD was that interface.
>
> Yes, Mach had to provide a BSD layer on top, but that's not the so= urce
> of Larry's gripes.
>
> It's the other way around. 4.4 BSD pulled the VM code out of Mach = and
> into BSD to provide mmap and some level of portability off the Vax. Fr= om
> there the Mach code got into FreeBSD.=C2=A0 That's what Larry is c= omplaining
> about and what Lyndon is saying isn't fair to the Mach guys.

Thank you for this clarification, so this conversation has been going on si= nce the 80=E2=80=99s and gets ignited from time to time.

Yea, there's been three or four rounds of rototilling= in the FreeBSD vm. While it shares some structures with its Mach ancestors= , complaining about it to paint Mach as this or that is unfair.
<= br>
FreeBSD's sys/vm has had a crapton of changes to make to = scale in an MP system, to adopt non-uniform page sizes, etc. Some of these = changes have been done with skill and subtly. Some have been done by a ham-= fisted goober. It would overstate things to say the most recognizable part = of Mach is the copyright headers :), but those bits are arguable the most u= nchanged. What's resulted lacks architectural purity because it wasn= 9;t designed from scratch to be pure. It's grown organically over the l= ast 30-odd years as different groups, companies and organizations have foun= d it necessary to fund development.

The SunOS 4.x = code, which was almost donated to the BSD project only to be scuttled at th= e last minute, has the twin advantages of being purpose built for only two = architectures and didn't need to scale to thousands of CPUs, and stoppe= d evolving in the 90s. As such, it can maintain its architectural purity si= nce it's not needed to grow and adapt since then. All that "growth= " happened in Solaris. So it's also a bit unfair to compare that c= ode which was developed over a decade to FreeBSD's.

But yea, DARPA was about networking in the Unix world. BSD was Unix a= t the time since AT&T didn't have the business structure to do the = contracts, and BSD's 2BSD or 3BSD was little more than a slightly more = evolved V7 research edition with some really cool user land features and a = few more drivers for hardware BSD users had. The Mach VM came late to the g= ame and was never the focus of the DARPA contracts.

For another view on how well CSRG integrated Mach into BSD, see NetBSD= 9;s uvm, a complete rewrite.

Warner
--00000000000056568d058c4f6552--