From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: tuhs-bounces@minnie.tuhs.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 14869bd5 for ; Mon, 24 Sep 2018 11:48:17 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 8275AA1DE6; Mon, 24 Sep 2018 21:48:16 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 08504A1DCC; Mon, 24 Sep 2018 21:48:07 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 05794A1DCC; Mon, 24 Sep 2018 21:48:06 +1000 (AEST) Received: from mercury.lcs.mit.edu (mercury.lcs.mit.edu [18.26.0.122]) by minnie.tuhs.org (Postfix) with ESMTPS id A86D394119 for ; Mon, 24 Sep 2018 21:48:05 +1000 (AEST) Received: by mercury.lcs.mit.edu (Postfix, from userid 11178) id CFF9B18C082; Mon, 24 Sep 2018 07:48:04 -0400 (EDT) To: tuhs@minnie.tuhs.org Message-Id: <20180924114804.CFF9B18C082@mercury.lcs.mit.edu> Date: Mon, 24 Sep 2018 07:48:04 -0400 (EDT) From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Subject: Re: [TUHS] SPARC is CRAPS spelled backwards. X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jnc@mercury.lcs.mit.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > From: Paul Winalski > In general, a CISC instruction set encoding can express the same > algorithm more compactly than a RISC instruction set. I have often pointed to memory bandwidth as one of the key factors in the evolution of CISC and RISC. When it was low, compared to CPU speeds (most of the core era), CISC made sense. When it increased (with DRAM), RISC made more sense, because it allowed CPUs to run faster (via simpler instructions). Caching made the picture a little more complex; and today, with the incredible mismatch between memory speeds and CPU speeds, caching dominates, whether you have RISC or CISC. Noel