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Re: 32G ram

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On 12/19/2012 12:20 PM, Arne Vajhøj wrote:
> On 12/19/2012 12:51 PM, Tim Slattery wrote:
>> Arne Vajhøj <arne@vajhoej.dk> wrote:
>>> A system with PAE can utilize the RAM by having multiple
>>> processes each having 2 or 3 GB virtual address space
>>> mapped into real RAM.
>>
>> Any Windows XP, Vista, Win7, etc 32-bit system can do that, PAE or
>> not. That's what the virtual memory system is all about.
>
> Yes.
>
> But non-PAE systems can only access 4 GB of RAM.
>
>>                                                        Each process
>> - and there are dozens running at any time - thinks it has a 4GB space
>> all to itself.
>
> Each process has 4 GB of virtual address space.
>
> Virtual address space gets translated to physical addresses
> by the CPU using pagetables.
>
> Without PAE the pages tables contain 32 bit physical addresses.
>
> With PAE the page tables contain 36 bit physical addresses.
>
> Which is why non-PAE systems cam only have 4 GB of RAM and PAE
> systems can have 64 GM of RAM.
>
> Note that desktop versions of Windows prevents more than
> 4 GB of RAM even with PAE.
>

but, you can still have a bit more in terms of swap-space though.

say, 16GB in swap-files.

this does require doing a few things manually though, as IIRC, 32-bit 
Windows only allowed about 4GB of swap-space per-drive.


granted, yes, things don't really run well.
back in those days, it was a great challenge trying to, say, run 
Borderlands and Firefox at the same time. it would require killing off 
Firefox for Borderlands to run ok.

this was an advance of 64-bit Windows over 32-bit Windows:
now a person can have a lot more apps running.


before then, multicore was an advance over single-core, as then 
background apps wouldn't so much interfere with foreground apps.

before then, XP was an advance over 9x, as it didn't crash as often.
and, Win9x was an advance over 3.x, in that a frozen app would not 
(generally) lock up the OS in 9x...

oh, the good old days, when hitting the power switch or reset button was 
much less uncommon...

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32G ram mcheung63@gmail.com - 2012-12-16 19:05 -0800
  Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-16 22:09 -0500
    Re: 32G ram Donkey Hottie <donkey@fredriksson.dy.fi> - 2012-12-17 10:39 +0200
      Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-17 17:37 -0500
        Re: 32G ram Lew <lewbloch@gmail.com> - 2012-12-17 15:38 -0800
      Re: 32G ram Nigel Wade <nmw@ion.le.ac.uk> - 2012-12-18 09:19 +0000
        Re: 32G ram BGB <cr88192@hotmail.com> - 2012-12-18 14:57 -0600
        Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-18 20:22 -0500
          Re: 32G ram Nigel Wade <nmw@ion.le.ac.uk> - 2012-12-19 11:28 +0000
            Re: 32G ram BGB <cr88192@hotmail.com> - 2012-12-19 07:19 -0600
            Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-19 09:17 -0500
              Re: 32G ram Tim Slattery <Slattery_T@bls.gov> - 2012-12-19 12:51 -0500
                Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-19 13:20 -0500
                Re: 32G ram BGB <cr88192@hotmail.com> - 2012-12-19 12:40 -0600
                Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-19 13:56 -0500
  Re: 32G ram Roedy Green <see_website@mindprod.com.invalid> - 2012-12-17 00:31 -0800
    Re: 32G ram Arne Vajhøj <arne@vajhoej.dk> - 2012-12-17 20:37 -0500
  Re: 32G ram Sven Köhler <remove-sven.koehler@gmail.com> - 2012-12-19 20:40 +0100

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