Re: 64-bit embedded computing is here and now

From	Dimiter_Popoff <dp@tgi-sci.com>
Newsgroups	comp.arch.embedded
Subject	Re: 64-bit embedded computing is here and now
Date	2021-06-08 23:39 +0300
Organization	TGI
Message-ID	<s9okhu$e58$1@dont-email.me> (permalink)
References	<7eefb5db-b155-44f8-9aad-7ce25d06c602n@googlegroups.com> <87lf7kexbp.fsf@nightsong.com> <s9n10p$t4i$1@dont-email.me> <Iyz*Vc+ly@news.chiark.greenend.org.uk> <s9ojag$4ce$1@dont-email.me>

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On 6/8/2021 23:18, David Brown wrote:
> On 08/06/2021 16:46, Theo wrote:
>> ......
> 
>> Memory bus/cache width
> 
> No, that is not a common way to measure cpu "width", for many reasons.
> A chip is likely to have many buses outside the cpu core itself (and the
> cache(s) may or may not be considered part of the core).  It's common to
> have 64-bit wide buses on 32-bit processors, it's also common to have
> 16-bit external databuses on a microcontroller.  And the cache might be
> 128 bits wide.

I agree with your points and those of Theo, but the cache is basically
as wide as the registers? Logically, that is; a cacheline is several
times that, probably you refer to that.
Not that it makes much of a difference to the fact that 64 bit data
buses/registers in an MCU (apart from FPU registers, 32 bit FPUs are
useless to me) are unlikely to attract much interest, nothing of
significance to be gained as you said.
To me 64 bit CPUs are of interest of course and thankfully there are
some available, but this goes somewhat past what we call  "embedded".
Not long ago in a chat with a guy who knew some of ARM 64 bit I gathered
there is some real mess with their out of order execution, one needs to
do... hmmmm.. "sync", whatever they call it, all the time and there is
a huge performance cost because of that. Anybody heard anything about
it? (I only know what I was told).

Dimiter

Thread

64-bit embedded computing is here and now James Brakefield <jim.brakefield@ieee.org> - 2021-06-07 07:47 -0700
  Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-07 14:13 -0700
  Re: 64-bit embedded computing is here and now Paul Rubin <no.email@nospam.invalid> - 2021-06-07 22:31 -0700
    Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-08 07:59 +0200
      Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 00:39 -0700
        Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-08 13:04 +0200
          Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 17:30 -0700
            Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-09 09:17 +0200
              Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 03:12 -0700
                Re: 64-bit embedded computing is here and now George Neuner <gneuner2@comcast.net> - 2021-06-12 12:58 -0400
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-12 12:40 -0700
              Re: 64-bit embedded computing is here and now Paul Rubin <no.email@nospam.invalid> - 2021-06-09 09:41 -0700
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 10:12 -0700
                Re: 64-bit embedded computing is here and now DJ Delorie <dj@delorie.com> - 2021-06-09 13:16 -0400
                Re: 64-bit embedded computing is here and now Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2021-06-09 13:44 -0400
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 22:03 +0300
                Re: 64-bit embedded computing is here and now Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2021-06-09 15:22 -0400
                Re: 64-bit embedded computing is here and now Paul Rubin <no.email@nospam.invalid> - 2021-06-09 12:58 -0700
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 16:26 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 23:12 +0300
        Re: 64-bit embedded computing is here and now James Brakefield <jim.brakefield@ieee.org> - 2021-06-08 12:38 -0700
          Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-08 22:11 +0200
            Re: 64-bit embedded computing is here and now James Brakefield <jim.brakefield@ieee.org> - 2021-06-08 14:25 -0700
            Re: 64-bit embedded computing is here and now George Neuner <gneuner2@comcast.net> - 2021-06-09 00:16 -0400
              Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-09 10:40 +0200
                Re: 64-bit embedded computing is here and now Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2021-06-09 22:52 +0200
                Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-10 09:37 +0200
          Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 01:01 +0300
            Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 18:29 -0700
              Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 20:56 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 17:12 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-10 13:45 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-10 06:55 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-10 18:32 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-10 14:09 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-11 01:13 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-10 21:55 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-11 14:14 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-11 05:10 -0700
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-11 16:35 +0300
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-11 16:24 -0700
              Re: 64-bit embedded computing is here and now George Neuner <gneuner2@comcast.net> - 2021-06-14 05:41 -0400
          Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 16:51 -0700
          Re: 64-bit embedded computing is here and now Paul Rubin <no.email@nospam.invalid> - 2021-06-08 18:20 -0700
            Re: 64-bit embedded computing is here and now Theo <theom+news@chiark.greenend.org.uk> - 2021-06-09 18:07 +0100
              Re: 64-bit embedded computing is here and now Paul Rubin <no.email@nospam.invalid> - 2021-06-09 10:34 -0700
                Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 16:37 -0700
              Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 16:43 -0700
      Re: 64-bit embedded computing is here and now Theo <theom+news@chiark.greenend.org.uk> - 2021-06-08 15:46 +0100
        Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-08 22:18 +0200
          Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-08 23:39 +0300
            Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 18:33 -0700
            Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-09 10:59 +0200
              Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 21:00 +0300
                Re: 64-bit embedded computing is here and now David Brown <david.brown@hesbynett.no> - 2021-06-09 20:55 +0200
                Re: 64-bit embedded computing is here and now Dimiter_Popoff <dp@tgi-sci.com> - 2021-06-09 22:06 +0300
        Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-08 16:00 -0700
          Re: 64-bit embedded computing is here and now Theo <theom+news@chiark.greenend.org.uk> - 2021-06-09 13:10 +0100
            Re: 64-bit embedded computing is here and now Don Y <blockedofcourse@foo.invalid> - 2021-06-09 06:19 -0700

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