Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Terje Mathisen Newsgroups: comp.arch Subject: Re: Is Intel exceptionally unsuccessful as an architecture designer? Date: Tue, 24 Sep 2024 07:50:36 +0200 Organization: A noiseless patient Spider Lines: 48 Message-ID: References: <21028ed32d20f0eea9a754fafdb64e45@www.novabbs.org> <20240918190027.00003e4e@yahoo.com> <920c561c4e39e91d3730b6aab103459b@www.novabbs.org> <%dAHO.54667$S9Vb.39628@fx45.iad> <4f84910a01d7db353eedadd7c471d7d3@www.novabbs.org> <20240923105336.0000119b@yahoo.com> <6577e60bd63883d1a7bd51c717531f38@www.novabbs.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Injection-Date: Tue, 24 Sep 2024 07:50:36 +0200 (CEST) Injection-Info: dont-email.me; posting-host="3651a7231ef7da6ad04f9fc6816c0f39"; logging-data="3264917"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+KEAWO3Q7gcfdA0CtsYB8JmBDFb78YrwUsE6KRgdCM0A==" User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0 SeaMonkey/2.53.19 Cancel-Lock: sha1:tacQJRKA02sA2fCJNfSJeFj68Us= In-Reply-To: <6577e60bd63883d1a7bd51c717531f38@www.novabbs.org> Bytes: 3658 MitchAlsup1 wrote: > On Mon, 23 Sep 2024 7:53:36 +0000, Michael S wrote: >=20 >> On Mon, 23 Sep 2024 01:34:55 +0000 >> mitchalsup@aol.com (MitchAlsup1) wrote: >> >>> On Mon, 23 Sep 2024 0:53:35 +0000, jseigh wrote: >>> >>>> On 9/22/2024 5:39 PM, MitchAlsup1 wrote: >>> >>>> Speaking of memory models, remember when x86 didn't have >>>> a formal memory model.=C2=A0 They didn't put one in until >>>> after itanium.=C2=A0 Before that it was a sort of processor >>>> consistency type 2 which was a real impedance mismatch >>>> with what most concurrent software used a a memory model. >>> >>> When only 1 x86 would fit on a die, it really did not mater >>> much. I was at AMD when they were designing their memory >>> model. >>> >>>> Joe Seigh >> >> >> Why # of CPU cores on die is of particular importance? >=20 > Prior to multi-CPUs on a die; 99% of all x86 systems were > mono-CPU systems, and the necessity of having a well known > memory model was more vague. Although there were servers > with multiple CPUs in them they represented "an afternoon > in the FAB" compared to the PC oriented x86s. When I started writing my first multi-threaded programs, I insisted on=20 getting a workstation with at least two sockets/cpus: Somebody wiser than me had written something like "You cannot=20 write/test/debug multithreaded programs without the ability for multiple = threads to actually run at the same time." Pretty obvious really, but the quote was sufficient to get my boss to=20 sign off on a much more expensive PC model. :-) Terje --=20 - "almost all programming can be viewed as an exercise in caching"