Quick question: 32bit to 64bit.

[zeroth404]

Any tips for migrating from a 32 to 64 bit processor?

I've got lots of packages listed in /etc/portage/package.keywords as ~x86. How do I make it so that gentoo will choose a 64 bit package over a 32 bit one? maybe a USE flag?

are the 64 bit packages separete forks of a project, or are they just simple modifications to the existing 32 bit code?

edit: I suppose I should make the "multilib" useflag global, in order to use 32 bit packages....right?

[techieMoe]

are the 64 bit packages separete forks of a project, or are they just simple modifications to the existing 32 bit code?

I can't help you with your Gentoo-specific questions, but on this one in my experience most 64-bit software packages are simply recompiled versions of their 32-bit counterparts, rather than a "fork" or anything resembling a rewrite. Most software these days does not take advantage of the new features offered by 64-bit processors.

[zeroth404]

I can't help you with your Gentoo-specific questions, but on this one in my experience most 64-bit software packages are simply recompiled versions of their 32-bit counterparts, rather than a "fork" or anything resembling a rewrite. Most software these days does not take advantage of the new features offered by 64-bit processors.

Gentoo Packages are soruce, with few binaries. forgive me if you already knew that.

If that is true, then every gentoo source package is going to be the same for either 32 or 64 bit processors.

In the Gentoo Package browser (http://packages.gentoo.org/), there are different categories for x86 and amd64 packages, so support is different for each.

Somebody shed some light on this?

[techieMoe]

Gentoo Packages are soruce, with few binaries. forgive me if you already knew that.

If that is true, then every gentoo source package is going to be the same for either 32 or 64 bit processors.

In the Gentoo Package browser (http://packages.gentoo.org/), there are different categories for x86 and amd64 packages, so support is different for each.

Somebody shed some light on this?

Yes, I'm aware that Gentoo runs off sources. My point is there are very few (if any) real rewrites of programs to take advantage of 64-bit instruction sets, so the fact that there are 2 codebases doesn't necessarily mean it's anything more than a copy of the 32-bit source intended to be recompiled.

But yes, I welcome a more informed view on the matter.

[d38dm8nw81k1ng]

TechieMoe, i think they're just the same source code copied to the ia64 repositories as they are declared stable and compatible. original poster, you need to edit make.conf to set your architecture as amd64, rebootstrap your system and recompile everything. not entirely sure but i'd imagine that's the general gist of what you'd need to do

[dennisraz]

I upgraded to a 64 bit processor 6 months ago and am running winxp64.
alot of software is incompatable with the version and driver support so far is terrible.
I would wait to move up and maybe get the dual core processors when they start coming down in price.

[spencerf]

you can also just keep using the 32 bit architecture with a 64 bit processor. But if you really want to take advantage of your new processor in gentoo you need to change your CFLAGS --specifically your march=k8 line. But if you want to use 64 bit gentoo I think you need to reinstall because with a stage three install you can't change your CHOST setting which is most likely set for a generic 32 bit processor i.e ["i686-pc-linux-gnu"]

If you just change your CFLAGS and keep 32 bit gentoo you need to

emerge -e system
emerge -e world

there probably is a way to migrate for 64 bit but in the end it would probably take just as long as reinstalling just back up any important data and reinstall with 64 bit version.

[d38dm8nw81k1ng]

you can change all the settings on a stage 3 make.conf, you just have to run the bootstrap and recompile your system to be compatible with the new settings.

[zeroth404]

I should have mentioned that I'm doing a fresh install while preserving my portage settings (make.conf, package.keywords, etc)

amd64 is supposed to be completely compatible with 32 bit software. If people are telling me its not, then I'm going to start worrying....

can anyone confirm a Windows 2000, Windows 98, and Linux installation (compiled from source, 2.6 stable) both run perfectly fine?

[techieMoe]

amd64 is supposed to be completely compatible with 32 bit software. If people are telling me its not, then I'm going to start worrying....

AMD64 computers are absolutely, completely, incontravertably compatible with 32-bit software. That's all I run on my AMD64. If anyone tells you different, they're wrong.

can anyone confirm a Windows 2000, Windows 98, and Linux installation (compiled from source, 2.6 stable) both run perfectly fine?

What you're describing is a simple dual-boot system. Yes. Quite a few of us have similar setups and they work just fine.