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_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FROM,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 25270 invoked from network); 22 Dec 2022 17:35:17 -0000 Received: from minnie.tuhs.org (50.116.15.146) by inbox.vuxu.org with ESMTPUTF8; 22 Dec 2022 17:35:17 -0000 Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 968BC41754; Fri, 23 Dec 2022 03:34:55 +1000 (AEST) Received: from mail-lj1-f169.google.com (mail-lj1-f169.google.com [209.85.208.169]) by minnie.tuhs.org (Postfix) with ESMTPS id B261140146 for ; Fri, 23 Dec 2022 03:34:50 +1000 (AEST) Received: by mail-lj1-f169.google.com with SMTP id n1so2622833ljg.3 for ; Thu, 22 Dec 2022 09:34:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.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=LO7C77V3hv6H1TZwcxKeGfFLF36fuaygxWURnqr0Kdk=; b=G4zlEcQXW8dbkMsR3od540iPmXzF452t4O1AJ3Mg0dM88YJp6LrZquE2efxpr1jwDi IZC42cV61aMCDZkqyawMgutJPa5fqBYBK0pE/WKQR43m1JpJnbMy4Otm5Gp1KNfHKKgQ dQ4fyl3bBLfBs8IM8urioBKSc/lsa+jAD00/nQL7lRHImDA8zC9g+APcqmAcX9PdnA3s LtjEjmAOeobHSbPt5HZ9MOGScPnWH/FhHahsRpA195aM83bvdgB5zi3vvoNuwe004KVc TwLgfRr3ne3MmNrUOK1hSt+E0+fU8lmqY4U/V52S231U5OI/w20aufqoWduNo0gdKu6Y nWKg== 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=LO7C77V3hv6H1TZwcxKeGfFLF36fuaygxWURnqr0Kdk=; b=kSAi7bOD9vWebhRlAypShaq1wFfqFGqwX/uwSNuobIqkT6scapgtyvL4ikvb7WNYzV IIqvIfPw9k74OnW1kEzn7s+hGiur0xW54+auI2kyQYy1JiIO6Ijo/MsZ0SDPdeaVwZtY g5TiCM23gfcBEAAl/Wb0Fh7nJkJ7nr/XI+eUY/2effSWTu++qOryGb6D5TyjyIBwbghe cIQ+svKNFgsdTJOtIaN8ZaNOXV67t7HZc7mywmOZf6/fh2w+rqtkfMfSbSx3sPzq/i6O AWfSpfa33KkOuAJDYdyC0Guun2D40gaTIYST/NJPTri/lpMEoByF9MSCZBmg/amVAK43 9ejg== X-Gm-Message-State: AFqh2ko4tQwI4N2FiYkmb2QeeYQ+DDYLwxvbJOU/WADdcuXq/dpYQejm k1n2Q85Ck8ubIZ2lH3S7sQCIjm2Ny5gKdaatV/UioVDAxcw= X-Google-Smtp-Source: AMrXdXtLnfNbEdbgnzb9ZmVtf7myPDZTVA5q2qrFyqInU3PfGpi+dPtKJcIlz715FIAmAnVLUKqHxC//5q72YZlPPpg= X-Received: by 2002:a2e:9919:0:b0:279:bb68:f1bc with SMTP id v25-20020a2e9919000000b00279bb68f1bcmr275198lji.445.1671730428968; Thu, 22 Dec 2022 09:33:48 -0800 (PST) MIME-Version: 1.0 References: <20221222172654.965D618C079@mercury.lcs.mit.edu> In-Reply-To: <20221222172654.965D618C079@mercury.lcs.mit.edu> From: Dan Cross Date: Thu, 22 Dec 2022 12:33:12 -0500 Message-ID: To: Noel Chiappa Content-Type: text/plain; charset="UTF-8" Message-ID-Hash: YTMTTPVWWPO4IJI5IUYNFHEQEME6HKQL X-Message-ID-Hash: YTMTTPVWWPO4IJI5IUYNFHEQEME6HKQL X-MailFrom: crossd@gmail.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: tuhs@tuhs.org X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: UNIX on (not quite bare) System/370 List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Thu, Dec 22, 2022 at 12:27 PM Noel Chiappa wrote: > > > From: Bakul Shah > > > There is a further para: > > > Reducing external memory fragmentation to zero by utilizing the VAX- > > 11/780 memory mapping hardware for scatter loading is high on the list > > of things to do in the second implementation pass. > > I'm curious as to exactly what is meant by "external memory"? They must mean > memory on the Synchronous Backplane Interconnect: > > http://gunkies.org/wiki/Synchronous_Backplane_Interconnect > > I.e. what most of us would call 'main memory'. > [snip] I think you left off a critical word: "fragmentation." I interpreted this to be about external memory fragmentation a la memory allocators. As in, https://en.wikipedia.org/wiki/Fragmentation_(computing)#External_fragmentation Presumably, this would be less of an issue if they were actually making use of the virtual memory hardware to compose contiguous virtual address spaces from discontiguous physical memory pages. - Dan C.