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19

Because AMD was the first one to release 64-bit x86 (x86-64) CPUs. the AMD64 architecture was positioned by AMD from the beginning as an evolutionary way to add 64-bit computing capabilities to the existing x86 architecture, as opposed to Intel's approach of creating an entirely new 64-bit architecture with IA-64. The first AMD64-based processor, ...


17

Native support Since Ubuntu 11.04 and Debian wheezy (7.0), Debian and Ubuntu have multiarch support: you can mix x86_32 (i386) and x86_64 (amd64) packages on the same system in a straightforward way. This is known as multiarch support See warl0ck's answer for more details. In older releases, Debian and Ubuntu ship with a number of 32-bit libraries on ...


12

Type grep lm /proc/cpuinfo (lm stands for long mode) Or just try booting with a 64-bit OS: if you do not have 64-bit support, it will say so and not boot. lm: Long Mode (x86-64: amd64, also known as Intel 64, i.e. 64-bit capable)


11

From Wikipedia: “In 2004, the initial 32-bit x86 instruction set of the Pentium 4 microprocessors was extended by the 64-bit x86-64 set.” Your /proc/cpuinfo output shows flags: … lm …. The flag lm stands for “long mode“ which means 64-Bit extension. Thus, you have indeed a 64-bit processor.


11

Since Ubuntu 11.04 (natty) and Debian 7.0 (wheezy) introduced multiarch support, 32-bit and 64-bit libraries can coexist on one system. To install a 32-bit library libXX, first add the 23bit architecture to your system: For Ubuntu: sudo dpkg --foreign-architecture i386 And for Debian: sudo dpkg --add-architecture i386 Then install the 32bit library: ...


11

The short answer: Variables do not take double the space in 64-bit vs 32-bit software. The potential memory gain from switching to a 32-bit OS will not be worth the effort. The long answer: Numbers can be larger yes, but that doesn't mean they will be. Also this applies to numbers, not strings, and strings are (generally) what consume the most amount of ...


11

AMD intially implemented x86-64, before Intel. For this reason, most distros (and other OSs such as OpenBSD) did a first release when it was still AMD only, or renaming to x86-64 wasn't considered worth the effort. I think one of the another contributing factors to this naming confusion was a conflict between Intel and AMD over naming. Intel had an identity ...


9

32-bit x86 CPUs (since the Pentuim Pro) support up to 64 GiB RAM (using PAE). (The "CONFIG_HIGHMEM64G" kernel option needs to be set to actually use it). Each application can only see 4 GiB at a time (and some of that 4GiB must be used for other things, the exact amount depending on the "Memory split" kernel setting) 64-bit operating systems have some other ...


9

Most open-source software has been working in 64-bit for quite a while. For proprietary software, many 64-bit applications are already available, but sometimes they don't work as well as they do in 32-bit. Flash, proprietary codecs etc... should work. Maybe if you have any hardware which requires proprietary drivers - and even then, most of those drivers ...


7

I assume that you're wondering about amd64 vs i386, the 64-bit and 32-bit architectures on PCs (there's also a choice of word size on Sparc64). According to the official platform description: The only major shortcoming at this time is that the kernel debugger ddb is somewhat poor. Another mentioned limitation is that if your processor lacks the NX bit ...


7

If your laptop has more than 3.5GB of RAM installed, you will want to install a 64 bit edition in order to take advantage of the full amount of RAM. General use of x64 operating systems is becoming more and more widespread. I run a x64 bit version of Linux on my desktop and have no issues. If you install a x64 bit version, however, there are some caveats: ...


6

With regard to eclipse not being able to find adb, etc, this because without the 32-bit shared libraries needed to run them on the system, they are not executable. With regard to 32-bit libraries, the situation is fairly simple: you just need to install the appropriate 32-bit libs. On the 64-bit fedora 17 install I have here, the primary 64-bit libraries ...


6

All your ram is accessible even with a 32bit kernel. The main difference is probably that any application cannot address more than 3gb of memory. I don't know if you really use such applications (usually databases, or graphics applications), otherwise you may ignore the problem. Please note that 64bits applications requires more memory (because registers and ...


5

The main benefit to 64-bit systems is the increased memory address space which is limited to 4GB with 32-bit systems. This question on the Superuser SE might be helpful: 32-bit vs. 64-bit systems. Also, here's an informal exploration of 32-vs-64 bit OSes on LifeHacker (though it focuses on Windows, much of it applies I think)


5

In most distributions there is a PAE version of the Kernel. This kind of Kernel will let you address up to 64GB RAM with a 32-bit distribution. You will find problems with some applications not available in 64 bits, like flash. And with other applications you will have to install x64 and i386 libraries duplicating the amount of necessary space. Another ...


4

Both VMware and VirtualBox can run a 64-bit virtual machine on a 32-bit host system, if you have a 64-bit processor. For VirtualBox, your processor must have hardware virtualization support (either AMD-V or VT-x, shown as svm and vmx in the flags: line of /proc/cpuinfo under Linux); most x86-64 processors except for the earlier ones, and in particular I ...


4

Gilles points out that I was mistaken about VirtualBox and VMware supporting 64-bit guests on 32-bit hosts. VirtualBox is available in the Ubuntu repositories in the virtualbox-ose package. VirtualBox's documentation provides the following advice regarding running 64-bit operating systems: VirtualBox supports 64-bit guest operating systems, even on ...


4

The main reason it usually comes down to (for home users) is the amount of memory installed on the device. 32-bit CPUs can only access ~3.7GB of RAM, while 64-bits can reach much much higher than that. If your netbook has more than 4GB of RAM (or you plan on installing more memory in the future), I would recommend 64 bit. In terms of software, there are ...


4

Generally speaking, user configuration files don't care about your architecture. I don't know of any exception in any current popular application. Of course, I can't exclude some weird program that stores binary data differently on x64 and amd64, but I wouldn't bet on you having any. You can share dot files between different distributions; there's nothing ...


4

Main advantages amd64 over i386 64-bit integer capability additional registers additional XMM (SSE) registers larger physical address space in legacy mode SSE/SSE2 for more details look at wiki page. What about performance? Actually performance will grow up to 20-30% in general case. Its mainly due to intelligent compilers that can optimize even ...


3

You have to install the 32 bit glibc: # yum install glibc.i686 This removes the misleading 'no such file or directory' message when trying to execute a 32 bit binary. With that the 64 bit Fedora system is capable of executing 64 bit binaries. This also removes the misleading 'not a dynamic executable' message of ldd when calling ldd on a 32 bit dynamic ...


3

It is in theory possible, but likely treacherous. Debian multiarch at current supports multiarch libs, but not binaries. So there's that. The system primarily understands its own architecture from dpkg-architecture (which is actually a perl script, but it extracts the arch info and displays it), which also claims to be able to set the architecture. ...


3

You need two things to cross-compile: a compiler that can generate code for the target architecture, and the static libraries (*.a) for the target architecture. Install at least the libc6-dev-i386 packages, and possibly other lib32.*-dev packages. The libc6-dev-i386 also pulls in the components of gcc needed for cross-compilation in the gcc-multilib package ...


3

You can't do that directly on Linux on x86_64 with a 32bit kernel. You need a 64bit kernel to be able to run 64bit code. (Note: kernel. You can have 32bit userland running on a 64bit kernel, and install support for 64bit binaries. How easy this is depends on the distribution. Example here for Debian.) Some virtualization software is able to do that (with ...


2

CentOS has an answer on their faq page about it, it is for compatibility with 32 bit stuff. To fix it, their answer says to add exclude = *.i?86 to your yum.conf. However if you have i386 rpms installed, updates will break so make sure you remove them before doing this. I prefer setting multilib_policy=best so in the oddball case you do need something 32 ...


2

There are quite a few manuals out there, but hardly any show what to really expect. I am writing this on a Debian Wheezy laptop that I just finished upgrading from 32 bit to 64 and it does indeed work. I followed these instructions and they were really accurate on what you will actually face: ...


2

TL;DR: It is doable, but complicated. I have outlined an alternative at the bottom. Now the long description, and take it with a grain of salt, as I may not have taken the best route: It is possible, and here is what I did for the last two nights: There is a wiki entry describing the old-school way without multiarch support. It is helpful for fixing broken ...


2

You are probably missing the i386 libc, try installing it with apt-get install libc6-i386. You can also add multiarch support to your system by running: dpkg --add-architecture i386 apt-get update Afterwards you can install a package for i386 with apt-get install package-name:i386 if it supports multiarch. For more information have a look at the ...


2

Each process runs in its own address space, and being 32-bit restricts that address space to about 3GB for each process. The sum of the memory used by 32-bit applications is completely irrelevant. There is nothing to get around. If this was a problem, chroot jails would not have the slightest chance of helping. They only affect paths to files.


2

If I understand your question you're asking how one would go about installing 32-bit packages under a 64-bit system. If this is indeed your question then I believe all one has to do is install the necessary packages that correlate to the architecture of the system. Most packages are available in both architectures, for example: $ apt-cache search ...



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