multilib or no-multilib - thats is the question

menschmeier · l33t Joined: 15 Dec 2004 Posts: 727

Hi,

I am planing to switch from x86 to an amd64 system. There are many questions about performance, availabilty of packages, ...

My question is what are the pros and cons of multilib?

I have some ideas:
pro:
- ability to run 32 bit apps (flash, win32codec, ... what else - I assume the the majority of programs will run in 64bit mode)

cons:
- more disk space needed (any idea how much this could be on a standard system?)
- longer compile times

Am I right, did I forget some points? Thanx for any ideas and hints.

menschmeier
_________________
Please notice the back of this message.

thedude0001 · Arch/Herd Tester Joined: 16 Jan 2005 Posts: 69

The "longer compile times" only applies to a few (toolchain) ebuilds like gcc, glibc, not to the vast majority of packages. These are currently handled via binary emul-linux-x86-* packages if needed. For the same reasons the additional space shouldn't be that much (I have no idea how much exactly, but it should be in the range of less than 250 mb, probably way less than that).
One thing you should also keep in mind is that you can change easily from multilib to no-multilib, but there is no way to change back if you realize that you've been wrong short of a reinstall. So if you can stand some MB more diskspace used and half an hour longer gcc compiles you should stick to multilib.
_________________
Das Schlimme auf dieser Welt ist
daß die Dummen so selbstsicher sind
und die Gescheiten so voller Zweifel.

rullzer · Posted: Tue Nov 21, 2006 12:21 am Post subject:

win32codecs should not be a pro. I run AMD64 with no multilib and mplayer plays wmv files etc for me.
flash is a big pro. But how often do you use flash? And besides i still have hope that soon the 64bit version of flash4linux comes..

Almost everything else works fine under amd64.

good luck with your choice,
rullz

i92guboj · Posted: Tue Nov 21, 2006 12:41 am Post subject:

About flash, there are a couple of ways around:

1.- To use gnash, still not too functional, but promissing.
2.- To install the package nsplugins32, you can do that manually, or thru the ebuild available in the berkano overlay.
3.- To install the nspluginswrapper package (haven't tested it, though)

The two last solutions are intended to run 32bits plugins into a 64 bits browser. So, you will still need multilib, but you dont have to install firefox-bin or anything like that. The only native solution for now that I am aware of is gnash.

About mplayer and win32codecs, the latest mplayer (and xine, I think) to ok with wmv9, not a problem. I personally use cvs builds of xine-lib, mplayer and ffmpeg, but I think that the latest in portage do ok as well, you might need to unmask them, though, not sure.

About the disk space, well, I am not sure either, but a build of the toolchaing can be around the 50 mb range or so, when talking about tarballs, so, I think that the additional stuff from having multilib should not be much bigger of that size, but have no real numbers about it. Appart from that, you will need the emul libs needed to run binary programs, that could be a few megabytes, not sure either, but in any case, it is nothing big.

The only thing that will need to be compiled twice is glibc, but, as amd64 is faster compiling, the time you will need is not doubled.

Regards.

menschmeier · l33t Joined: 15 Dec 2004 Posts: 727

Hi,
so I will give multi-lib a shot. Flash is not important to me so switching later to no-multi-lib for any reason should not have any bad effects.

Thanx
menschmeier
_________________
Please notice the back of this message.

thedude0001 · Arch/Herd Tester Joined: 16 Jan 2005 Posts: 69

There's a bit more packages than only those mentioned here which won't work on no-multilib. Check /usr/portage/profiles/default-linux/amd64/2006.1/no-multilib/package.mask for a full list.
_________________
Das Schlimme auf dieser Welt ist
daß die Dummen so selbstsicher sind
und die Gescheiten so voller Zweifel.

menschmeier · l33t Joined: 15 Dec 2004 Posts: 727

Hi,

thanks for that hint. I will stick with 32bit for a couple of months. This is because my laptop is broken and I will transfer the installation from its disk to my new laptop. So will have a running system quite fast - if it works like I expect it. But I am still waiting for the new hardware ... :-(

menschmeier
_________________
Please notice the back of this message.

likewhoa · Posted: Thu Dec 07, 2006 8:21 am Post subject:

multilib good for me, everything works and most i need is available or will be.
who needs the extra space used up with a chroot 32bit on amd64 no-multilib.

thedude0001 · Arch/Herd Tester Joined: 16 Jan 2005 Posts: 69

Well, running no-multilib and then building a 32bit chroot for your 32bit needs would be about the worst way to handle it. I'm not even sure if you could run a 32bit chroot on a no-multilib profile.

The idea of no-multilib is to be used by people who don't need 32bit support at all. As nearly everything has been ported to amd64 this can work. I'm administrating two amd64 servers which only run multilib because some windows users insist to send me data as .rar archives...
_________________
Das Schlimme auf dieser Welt ist
daß die Dummen so selbstsicher sind
und die Gescheiten so voller Zweifel.

likewhoa · Posted: Fri Dec 08, 2006 4:55 pm Post subject:

multilib to me is safer and less of a hassel than having a separate 32bit chroot that needs updating on top of your 64bit build.
amd64 is mature enough now

hvengel · Guru Joined: 19 Sep 2004 Posts: 515

I also use multi-lib but there are only a small handful of things that need it and the list is starting to get very small and this was pretty much covered above. So what it comes down to is do you or might you need or want anything on that list? Since multi-lib is so easy to setup and adds so little overhead I would say even if the answer is maybe run a multi-lib system. On the other hand amd64 is getting so mature that in a few more months it may no longer make sense to run a multi-lib system for most users.

thedude0001 · Arch/Herd Tester Joined: 16 Jan 2005 Posts: 69

I have my doubts about "in a few months", I'd rather say "in a few years". At least if you want to be sure that every not-dead application can run on your amd64.

FOSS projects aren't the ones that keep needing a 32bit environment (hell, even OOo was finally ported), the real showstopper here are proprietary programs. Flash, rar, VMWare, Google Earth, Games...

One thing I'm really looking forward to is native multilib support in portage (if it is ever completed), that would take care of those nasty emul-linux packages-x86...
_________________
Das Schlimme auf dieser Welt ist
daß die Dummen so selbstsicher sind
und die Gescheiten so voller Zweifel.