Arch Linux

crisnoh

Member

From: Baghdad, Iraq

Registered: 2008-04-22

Posts: 67

Website

Annoyed

So, I just realized that I have a 64 bit processor in my box.  I'm officially demoting myself right back to noob status.  I'm also hoping that the difference it would make is not enough to warrant my reinstalling.  Blech!

KimTjik

Member

From: Sweden

Registered: 2007-08-22

Posts: 713

Re: Annoyed

What's the question?

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,604

Re: Annoyed

There are no question marks in the first post, so I conclude that there is no question.

scrawler

Member

Registered: 2005-06-07

Posts: 312

Re: Annoyed

just in case there is a hidden question...

I would personally reinstall because it just seems right that a 64 bit machine should have a 64 bit os, but I don't think it makes all that much difference.

ladislaio

Member

From: Greenville, Pennsylvania

Registered: 2007-09-22

Posts: 14

Re: Annoyed

If you do not have more than 2 gigs of ram, I do not see the point of using 64 bit.  32 Bit is still more common and thus more supported - in particular WINE and Flash are bigger pains in 64 bit.  Of course apparently some things, like media encoding, work better in 64 bit (or so I have heard).  64 bit systems do not have to worry about 2038 either - so yes, you will have to re-install, but not for some time.

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mmm... Linux...

skottish

Forum Fellow

From: Here

Registered: 2006-06-16

Posts: 7,880

Re: Annoyed

If it helps you at all, most 64 bit processors are only using 40 bit address size anyway:

[skottish@iasE proc]$ cat /proc/cpuinfo | grep address
address sizes    : 40 bits physical, 48 bits virtual
address sizes    : 40 bits physical, 48 bits virtual

It's listed twice for the number of cores I have. So, your frustration level can drop by a lot!

theringmaster

Member

From: Air Force

Registered: 2007-07-16

Posts: 581

Website

Re: Annoyed

I run 64 bit arch just fine. Setting up flash is only a pain in the beginning (installing all the deps), but after it's ok. We now have a native java implementation in openjdk6 (in testing right now.

and skottish: I too see that my amd phenom x4 is only using 48bit addresses too

address sizes    : 48 bits physical, 48 bits virtual
address sizes    : 48 bits physical, 48 bits virtual
address sizes    : 48 bits physical, 48 bits virtual
address sizes    : 48 bits physical, 48 bits virtual

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skottish

Forum Fellow

From: Here

Registered: 2006-06-16

Posts: 7,880

Re: Annoyed

Since we're talking about it. Yeah I know it's already been done here (http://en.wikipedia.org/wiki/X86-64):

Virtual address space details

Although virtual addresses are 64 bits wide in 64-bit mode, current implementations (and any chips known to be in the planning stages) do not allow the entire virtual address space of 16 EB to be used. Most operating systems and applications will not need such a large address space for the foreseeable future (for example, Windows implementations for AMD64 are only populating 16 TB, or 44 bits' worth), so implementing such wide virtual addresses would simply increase the complexity and cost of address translation with no real benefit. AMD therefore decided that, in the first implementations of the architecture, only the least significant 48 bits of a virtual address would actually be used in address translation (page table lookup). However, bits 48 through 63 of any virtual address must be copies of bit 47 (in a manner akin to sign extension), or the processor will raise an exception. Addresses complying with this rule are referred to as "canonical form." Canonical form addresses run from 0 through 00007FFF`FFFFFFFF, and from FFFF8000`00000000 through FFFFFFFF`FFFFFFFF, for a total of 256 TB of usable virtual address space.

Onwards

Member

From: Pakistan

Registered: 2007-04-18

Posts: 108

Re: Annoyed

Intel64 and AMD64 are both implementations of x86-64. While x86-64 isn't true 64-bit architecture; it's just an extention to the x86 instruction set. Thus 32-bit Arch would run perfectly well on a Pentium D, Dual core or a Core2 Duo (all of them are x86-64).

It's also noteworthy that 32-bit Arch won't run efficiently on an Itanium-based [IA-64] machine, which is different than x86-64.

11010010110

Member

Registered: 2008-01-14

Posts: 284

Re: Annoyed

We dont have 2^64 ram and not even 2^40 ram. I think the question is about the work of the cpu itself

Since i dont have any stuff like flash or wine and i like to mess up with my system i'd sure reinstall

wuischke

Member

From: Suisse Romande

Registered: 2007-01-06

Posts: 630

Re: Annoyed

It's also noteworthy that 32-bit Arch won't run efficiently on an Itanium-based [IA-64] machine, which is different than x86-64.

Actually it won't run unless virtualized/emulated. At work they are doing FEM simulations (amongst others for the automobile industrie) and we've a couple of Itanium boxen...although I like the old discarded SGI O2s better...they're cute.

To OP: No reason to reinstall unless you like to learn new stuff and work around some limitations. I'm back to Arch i686 now, too. (Well, this was because I downloaded and burned the wrong ISO and didn't realize until after having installed the system...but don't tell anyone!)