Re: Install i386 or amd64?

[jmitchel%bigjar.com@localhost]

>
> On Jan 29, 2014, at 15:07, jmitchel%bigjar.com@localhost wrote:
>
>>> On Tue, Jan 28, 2014 at 06:26:13AM -0500, Jason Mitchell wrote:
>>>>
>>>> Not to advocate i386 over amd64, but doesn't NetBSD/i386 support PAE
>>>> and
>>>> thus can access >2GB of RAM?
>>>>
>>>
>>> You are still limited to a 32bit address space in the process so you
>>> still can't go over the 4Gb memory limit and that is divided between
>>> kernel and user space hence why a process gets 2(ish)Gb.  These
>>> limitations don't apply to a true 64bit system.
>>>
>>> --
>>> Brett Lymn
>>> Staple Guns: because duct tape doesn't make that KerCHUNK sound -
>>> xkcd.com
>>>
>> Please don't post about things that you don't understand. Here's the
>> information from Wikipedia:
>>
>> http://en.wikipedia.org/wiki/Physical_Address_Extension
>>
>> And here's the first four lines:
>
> Did you even read the whole thing? Because you should... the first four
> lines don't tell all there is to know about it. Read further and be
> educated: "The 32-bit size of the virtual address is not changed, so
> regular application software continues to use instructions with 32-bit
> addresses and (in a flat memory model) is limited to 4 gigabytes of
> virtual address space."
>
> Just as Brett said: "You are still limited to a 32bit address space in
> the process so you still can't go over the 4Gb memory limit"
>
>
Dave,

Okay, here's the original quote:

>>>> Not to advocate i386 over amd64, but doesn't NetBSD/i386 support PAE
>>>> and
>>>> thus can access >2GB of RAM?
>>>>
>>>
>>> You are still limited to a 32bit address space in the process so you
>>> still can't go over the 4Gb memory limit

When did we start talking about a per-process limit, versus how much
memory the OS can operate? This is an important distinction to make, given
that the original poster said:

"Actually the B590 comes with 2GB RAM"

That's the laptop he was installing NetBSD on. And laptops or desktops
with 2,4, or 8GB are going to common machines that users could ask about
installing NetBSD on. Mentioning a 4GB per process limit to these people
is absurd. I wondered whether if a per process limit was what Brett was
talking about, but his writing was unclear and the point made no sense
given the original thread. If other users have questions about what port
to run on a laptop or desktop and read this thread it would just confuse
them. This is netbsd-users, not tech-kern, or even port-i386/port-amd64.

I think he (and maybe you) just want to show how smart you are, tossing
out facts that are meaningless trivia in the current context, rather than
paying attention to and answering questions from users.

If you or he wanted to make the point about the limitations of PAE without
confusing people needlessly, it needed to be written much clearer and with
caveats as to who the per-process limit would impact.

Jason M.