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 c660bf7d for ; Sat, 31 Aug 2019 00:59:30 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id B546F9C0CD; Sat, 31 Aug 2019 10:59:28 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id B7A399C092; Sat, 31 Aug 2019 10:58:33 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=ccc.com header.i=@ccc.com header.b="Ek0q+smu"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 5D2099C092; Sat, 31 Aug 2019 10:58:30 +1000 (AEST) Received: from mail-wm1-f65.google.com (mail-wm1-f65.google.com [209.85.128.65]) by minnie.tuhs.org (Postfix) with ESMTPS id 9B9659C07F for ; Sat, 31 Aug 2019 10:58:29 +1000 (AEST) Received: by mail-wm1-f65.google.com with SMTP id d16so9116941wme.2 for ; Fri, 30 Aug 2019 17:58:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ccc.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qHdzRWA2nYSi1FW1OaiFqzcXXTvvViOyH0SM+/ytziI=; b=Ek0q+smuM5SX4aY6Tnuq7apP01h39cPlLaCOa+vaOlQQvP5geXGoI4lxHgzuH839rW HzfU8xx5Diu+MegJYNIGVpXeQo0CYOmvszuXafEFR5YNAO8eTcc5vzhxtGV6A9zh0/Hg 6LHpnvyOSpBC7PTLhrMSOnw2hjZvgSKKjQ6Do= 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=qHdzRWA2nYSi1FW1OaiFqzcXXTvvViOyH0SM+/ytziI=; b=pwPC9TkUoy+EH+ddVq57Nnpd6UuPmvYxoVabfr9T9z7ZTGdM7retzREGQ3kCR7h88R qf8c+QmkkPyIbrrLyPO0JuIYDEm1A2XLFnoofuh/BZvjFgw/BpWyKLhUffd22TiKX7Qq 9rq3k51dbZrCbJzQ++567JHVO+ILBd64AirVgRJbjomaBPGJ01UPexAo581+n8CivqyS K8TPwyWz4p+4Skn/7yYD4dU2n6fVyjWPgiCxuLZAObORCeQdpEDE1n/hQ2KIZ8gT9JiB fOKCBwxu8S6F3xTpHZPV+BLELL/1PmgThnXAg5fnNGfPURC9ISEG/UUJ/PKrwdnsGRvZ 8cfQ== X-Gm-Message-State: APjAAAV7BxtwsIaY7++jeW7sO6mUmw4+ukbKhHylVh7VWrPwbhUElmSj iSQwZsfmzlzrA69jSOEFhs/lJD5yE/yU/jNiD2mYUQ== X-Google-Smtp-Source: APXvYqxNhWMBtfvT54Eb2+3B7GDGRbEJiz5eHpVQOqToMu3d38ROUxUCFNPCZbAo73yBPq7MH0/VPIr9EzGOblqCJfM= X-Received: by 2002:a05:600c:228c:: with SMTP id 12mr15707470wmf.33.1567213107807; Fri, 30 Aug 2019 17:58:27 -0700 (PDT) MIME-Version: 1.0 References: <1567196510.21824.for-standards-violators@oclsc.org> <20190830215202.GA974@mcvoy.com> In-Reply-To: <20190830215202.GA974@mcvoy.com> From: Clem Cole Date: Fri, 30 Aug 2019 20:58:13 -0400 Message-ID: To: Larry McVoy Content-Type: multipart/alternative; boundary="00000000000094198c05915f3c01" Subject: Re: [TUHS] dmr streams & networking [was: Re: If not Linux, then what?] 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: The Eunuchs Hysterical Society Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" --00000000000094198c05915f3c01 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Actually not in lock step. They were independent. One was called the executor and the other the fixer. When a fault was detected the executor was sent wait stated while the fixer handled the fault and refilled the TLB. Once the TLB was set to instruction was allowed to complete. Btw when the 68010 was released the pals on the board were changed to allow the executor to actually take the fault and do something else while the fixer replaced the TLB entry The idea was proposed by Forest Baskett at an early Asilomar conference but never built by him - I want to say 1980 or 81. I have lost that paper and would love to find a copy again BTW. To be fair both Apollo and Masscomp=E2=80=99s hw teams reduced the idea to practice independently but = I know of no other folks that tried it. On Fri, Aug 30, 2019 at 5:52 PM Larry McVoy wrote: > On Fri, Aug 30, 2019 at 04:39:09PM -0400, Clem Cole wrote: > > MC-500/DP was the first MP Unix >>product<< -- predates our friends in = on > > the West coast by 2 years). > > And as I recall you had to do 2 68000's in lockstep to get the VM system > to do page fault restarts. That was neat, was that a Masscomp invention > or was it a commonly known trick? > > --lm > --=20 Sent from a handheld expect more typos than usual --00000000000094198c05915f3c01 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Actually not in lock step.=C2=A0 They were independe= nt.=C2=A0 One was called the executor and the other the fixer.=C2=A0 When a= fault was detected the executor was sent wait stated while the fixer handl= ed the fault and refilled the TLB. =C2=A0 Once the TLB was set to instructi= on was allowed to complete. =C2=A0 =C2=A0Btw when the 68010 was released th= e pals on the board were changed to allow the executor to actually take the= fault and do something else while the fixer replaced the TLB entry

The idea was proposed by = Forest Baskett at an early Asilomar conference but never built by him - I w= ant to say 1980 or 81. =C2=A0 =C2=A0I have lost that paper and would love t= o find a copy again BTW. =C2=A0 =C2=A0To be fair both Apollo and Masscomp= =E2=80=99s hw teams reduced the idea to practice independently but I know o= f no other folks that tried it. =C2=A0

On Fri, Aug 30, 2019 at 5:52 PM = Larry McVoy <lm@mcvoy.com> wrote:=
On Fri, Aug 30, 2019 at 04:39:09PM= -0400, Clem Cole wrote:
> MC-500/DP was the first MP Unix >>product<< -- predates ou= r friends in on
> the West coast by 2 years).

And as I recall you had to do 2 68000's in lockstep to get the VM syste= m
to do page fault restarts.=C2=A0 That was neat, was that a Masscomp inventi= on
or was it a commonly known trick?

--lm
--
Sent from a handheld expect more typos t= han usual
--00000000000094198c05915f3c01--