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=-0.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, HTML_MESSAGE,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 30911 invoked from network); 1 Jan 2023 06:28:52 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 1 Jan 2023 06:28:52 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 865804241E; Sun, 1 Jan 2023 16:28:29 +1000 (AEST) Received: from mail-ed1-f53.google.com (mail-ed1-f53.google.com [209.85.208.53]) by minnie.tuhs.org (Postfix) with ESMTPS id EE7F2423FB for ; Sun, 1 Jan 2023 16:28:23 +1000 (AEST) Received: by mail-ed1-f53.google.com with SMTP id z11so20187833ede.1 for ; Sat, 31 Dec 2022 22:28:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20210112.gappssmtp.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=LGIFsbL6U9DFO8FHgKrGfiHeGRbo7sMuo3BSHvFRmVg=; b=L2Juy3G8jBPnkvImj4vfXdYaP4m3PO7yuAohVEr+NtZTb8V8ZTSLDQVOENq976yiS1 stC7AQjeJvZ/agwFyzbEYSLMrzM3ucgBbsaVbhtRbqS4BHz5H39HKl9e9GDjoLYfJ7M/ vwUMOX8Z7iFUaflsonb37kCAEDNCil1OmDcVJaiR9JaNktbw7YMCCsbRW70yqiaXOYup CVaRvcpCMSnI4DkQEJixi/7xfOlXHw51M6awfHvecSXslALJ6F8a68BQJyGzCtUje/zi CoQfDZaF7omjVmbGPkzwSufiubVNBGkIyNN0rsZ5jbPXHzQDUJYickN530xtJbsgowJA 3pug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=LGIFsbL6U9DFO8FHgKrGfiHeGRbo7sMuo3BSHvFRmVg=; b=lFANQvvhYlpfDrp2k5c3ztPd3gweZSAoysIOAuAFdZbb+HAY2eWHBYWrU41G35d0ww QtIwqxWrXHvS1/VzEBGPQvuxlp4smzEv8o2aj1KQpc/Wn+zFEpCSsDTcvNT2alRZ4ddW D1CjHtoH5oyoo/MdzqFMgWCwfDCN/iGw4lC1kIKwgHBs53mwHTGk7QD3JO+1JDk5HX8y xcZDZ1VOwOx1S2OR1eZasEVm0nBeNiB6V7AUXSrSL8gG9lwSVhtQQ+yNDOgEdRIRnhYk g5KwGOef5UHj+vVqapCABmgYqxULgwYQwzasaHCQwtdrB+0/nqv4cwcwiUTHjlhc/vPp 9h9w== X-Gm-Message-State: AFqh2kr/IHPfXEagNFFrMXSewhSEdCaJJTCq6qOGM0OqG52QHw4MPXcr RQRXAKZV5c/vC6otMs/f0jcSd4qx42ab1YAKc7U0RA== X-Google-Smtp-Source: AMrXdXukf6ZsHoMkTDYkIwrY6jeOq7dGhqrk3UCARKUvC5aj1hBkeM/LiIfOke6MwU0PEXqy6eToc67hwBkgX8tTYAU= X-Received: by 2002:a05:6402:164a:b0:482:c049:67db with SMTP id s10-20020a056402164a00b00482c04967dbmr3568416edx.173.1672554442488; Sat, 31 Dec 2022 22:27:22 -0800 (PST) MIME-Version: 1.0 References: <52FB6638-AEFF-4A4F-8C2E-32089D577BA0@planet.nl> <18521483-A73C-4B5F-A76A-6098BD93E9BC@planet.nl> In-Reply-To: From: Warner Losh Date: Sat, 31 Dec 2022 23:27:11 -0700 Message-ID: To: Dan Cross Content-Type: multipart/alternative; boundary="00000000000069955605f12ded62" Message-ID-Hash: D6Y4D7TOSXMFQBDRQQVVNAQRT6JKHE2C X-Message-ID-Hash: D6Y4D7TOSXMFQBDRQQVVNAQRT6JKHE2C X-MailFrom: wlosh@bsdimp.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tuhs.tuhs.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Jonathan Gray , Paul Ruizendaal , The Eunuchs Hysterical Society , segaloco X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: A few comments on porting the Bourne shell List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: --00000000000069955605f12ded62 Content-Type: text/plain; charset="UTF-8" On Sat, Dec 31, 2022, 10:35 PM Dan Cross wrote: > On Sun, Jan 1, 2023 at 12:27 AM Warner Losh wrote: > > On Sat, Dec 31, 2022, 9:38 PM Jonathan Gray wrote: > >> [snip] > >> Bourne's AsiaBSDCon 2016 talk also lists 1976 > >> and goes on to discuss sbrk() use causing problems with ports > >> https://youtu.be/7tQ2ftt3LO8?t=715 > > > > And at 5:18 he says he had a vax lab with three vaxen and the Lab's vax > port didn't have virtual memory. Bill Joy with 3BSD which had virtual > memory. They installed it on the vaxen because they were hitting physical > memory limits for some of their programs.... > > One wonders what is meant by "virtual memory" in this context. I > contend that Unix has had "virtual memory" since moving off of the > PDP-11/20, in the sense of having a virtual address space that was > mapped onto a (possibly contiguous) physical address space. I think > all of these references mean demand paging, possibly with page > reclamation or whole-process swapping under memory pressure. > It's clear from context it's demand paging and that unlocks processes larger than physical memory. Imho. Warner > --00000000000069955605f12ded62 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Sat, Dec 31, 2022, 10:35 PM Dan Cross <crossd@gmail.com> wrote:
On Sun, Jan 1, 2023 at 12:27 AM Warner Losh <<= a href=3D"mailto:imp@bsdimp.com" target=3D"_blank" rel=3D"noreferrer">imp@b= sdimp.com> wrote:
> On Sat, Dec 31, 2022, 9:38 PM Jonathan Gray <jsg@jsg.id.au> wrote= :
>> [snip]
>> Bourne's AsiaBSDCon 2016 talk also lists 1976
>> and goes on to discuss sbrk() use causing problems with ports
>> https://youtu.be/7tQ2ftt3LO8?t=3D715
>
> And at 5:18 he says he had a vax lab with three vaxen and the Lab'= s vax port didn't have virtual memory. Bill Joy with 3BSD which had vir= tual memory. They installed it on the vaxen because they were hitting physi= cal memory limits for some of their programs....

One wonders what is meant by "virtual memory" in this context. I<= br> contend that Unix has had "virtual memory" since moving off of th= e
PDP-11/20, in the sense of having a virtual address space that was
mapped onto a (possibly contiguous) physical address space. I think
all of these references mean demand paging, possibly with page
reclamation or whole-process swapping under memory pressure.

It's clear = from context it's demand paging and that unlocks processes larger than = physical memory. Imho.

W= arner
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