Ubuntu 32bit vs 64bit
 

I have used Mint linux in the past but just as an experiment. I really liked the Mint distribution but I wanted to try Ubuntu. I got a book out of the library and used the disk to install Ubuntu 10.10. I did not pay attention to the fact that it was 32bit. I upgraded to the latest edition before I realized it was 32bit. I went to the Ubuntu download site to get the 64bit iso. On the site it has a note recommending the 32bit. I have two questions. First, is there a reason not to use the 64bit distribution? Second, if I decide to move to the 64bit system, what would be the best way to proceed?

1) 64-bit versions of the distros still have some incompatibilities and can be a little more difficult to set up. In my experience though, it's not a big deal.
2) I would backup your files and do a clean install

32 v 64 bit linux
 

What hardware are you running on? Older hardware may have better support on 32 bit in the way of drivers. Although Linux is v good on memory usage 64 bit tends to use more than 32 bit, so small memory is served better with 32bit. What processor do you have? Check on 64 bit support.

My rule of thumb P4 with small memory or pre 2005 hardware is better with 32 bit

I have plenty of resources on the machine. It is a Phenom quad core and there are 6 gigs of memory. This is the reason I wanted the 64bit so that I could better utilize the machine.

x86_64 came out years ago, please use it.

How much trouble is it to back up your files and settings and do a clean install of 64 bit?

Trying to upgrade (in place) an existing 32 bit install to 64 bit is beyond expert difficult. It is not flat out impossible, but close enough to impossible you shouldn't consider trying it.

Switching to 64 bit will probably not make a big difference. You're neither likely to see the problems others have mentioned, nor big benefits.

The benefits probably aren't worth the effort of reinstalling. But maybe you don't have much invested in files and settings in the 32 bit install and maybe your curiosity about the difference is enough to justify the effort of reinstalling.

If you don't switch, make sure your 32 bit install has a PAE kernel (if that is not the PAE kernel, it is very easy to install the PAE kernel from the package manager and then reboot).

For most uses of Linux, a 32 bit PAE kernel will utilize 6GB as well as 64 bit would.

For most uses of Linux, you have no real need of 6GB, so having 6GB just means the file cache will grow very big and some things will run a little faster because their file I/O is really in ram rather than on disk. That all happens just as well in PAE as in 64 bit.

Maybe you need 6GB because you have a bunch of fairly big service processes running in the background and/or you open up a lot of different applications and switch among windows as multiple programs continue running. 32 bit PAE does that as well as 64 bit.

It is rare to have a really big application that uses over 3GB in a process. If you want over 3GB in one process you need 64 bit. 32 bit PAE is limited to 3GB per process even though multiple processes plus caching can together make good use of far more.

It depends on how you want to use the system. I develop circuit simulation software and sometime run examples that take FAR more than 3GB of memory for one process. So I have no real use for 32 bit systems myself, but I know my own computer use is not in any way typical.

I doubt you really need the 64 bit. Since you have been happy before then why fool with it? Just let the thing do it's normal updates and when it comes time for a complete new OS then decide.

I will agree that even a newbie could benefit from some ram for their apps or programs but that and maybe some very small increase in some programs would be a reason to select 64 bit. As noted above there are still a few bugs. Ubuntu recommends what they believe to be a good choice. Neither choice is bad. You'd have to run a program for many hours to see some net gain in speeds usually in the 64 bit apps. They are compiled on newer programs and don't require any legacy tunings. They are not faster based on the bits.

Saying all that I tend to use 64 bit only because I am crazy.

My recommendation to anyone with a 64 bit processor is to use a 64 bit OS unless you cannot use a 64 bit for some strange reason such as hardware support (ndiswrapper comes to mind).

Ubuntu is moving towards 64 bit more and more, so much so that it will be recommended the next version (12.04) to use 64 bit. This is due to the fact that Debian, the distro that Ubuntu is derived from, has brought in Multiarch support into testing. If you have any applications that are 32 bit only you can still use them in current 64 bit systems by installing ia32-libs (and if your using Gnome or Unity ia32-libs-gtk as well).

Thank all of you for you information. Since I have just started with Ubuntu, I believe I will do the clean install,I have really very little to lose and then as the last post indicated I will be using the system that is the future.