Should I be running 64-bit OS's?

spoovy · 12-26-2010, 11:24 AM

I have always used 32-bit / x86 OS's on this hardware, as it didn't say x64 anywhere on the spec so I assumed it was x32.

I have just read though in a book that this processor is 64-bit. So, is it, and should I be using 64-bit OS's?

Or is something else a limiting factor ie the motherboard? I'm a bit confused to be honest, so any pointers welcome.

a snippet from lshw for info -

Code:

  *-core
       description: Motherboard
       product: G31D-M7
       vendor: BIOSTAR Group
       physical id: 0
       serial: None
       slot: To Be Filled By O.E.M.
     *-firmware
          description: BIOS
          vendor: American Megatrends Inc.
          physical id: 0
          version: 080014 (03/31/2009)
          size: 64KiB
          capacity: 448KiB
          capabilities: isa pci pnp apm upgrade shadowing escd cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi usb ls120boot zipboot biosbootspecification
     *-cpu:0
          description: CPU
          product: Pentium(R) Dual-Core  CPU      E5400  @ 2.70GHz
          vendor: Intel Corp.
          physical id: 4
          bus info: cpu@0
          version: 6.7.10
          serial: 0001-067A-0000-0000-0000-0000
          slot: CPU 1
          size: 2700MHz
          width: 64 bits
          clock: 200MHz
          capabilities: boot fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx x86-64 constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm xsave lahf_lm tpr_shadow vnmi flexpriority
          configuration: id=0

stress_junkie · 12-26-2010, 11:25 AM

The main difference between using 32 bit and 64 bit is the amount of RAM that the software can use. If you have more than 4 GB of RAM then you need to use 64 bit. Otherwise 32 bit is fine.

yooy · 12-26-2010, 11:36 AM

If your processor is 64bit it would be optimal to run 64bit version of linux

johnsfine · 12-26-2010, 12:10 PM

Quote:

Originally Posted by spoovy

should I be using 64-bit OS's?

It probably doesn't make much difference.

The commonly stated reasons for using a 64 bit OS are seriously exaggerated, for example:

Quote:

Originally Posted by stress_junkie

If you have more than 4 GB of RAM then you need to use 64 bit.

That really isn't true.

The commonly stated reasons for sticking with a 32 bit OS are also seriously exaggerated (such as incompatible drivers, etc.)

There are many situations in which switching to 64 bit would be a big improvement. But all of those are very unlikely for an ordinary user of Linux who might ask the question.

If you have 12GB or more of ram, that is a very good reason to switch to a 64 bit OS. If you have less than 0.5GB of ram, that may be a good reason to not switch to a 64 bit OS. In between those extremes the amount of ram you have should not have any significant effect on your decision of 32 bit vs. 64 bit.

TobiSGD · 12-26-2010, 12:31 PM

In my opinion it shouldn't depend on the amount of RAM in the system (if you don't have a extreme configuration), but it should depend on what you are actually doing with the system.
If you use the system only for office stuff or surfing the web you will hardly get any benefit from a 64 bit OS. But if you do lots of media encoding or work with big pictures or anything else what may count as "number crunching" you can get a good speed up from the change. This is because the packages for the most 64 bit OS can be (and are) compiled with more optimizations. For example can SSE2 optimization be enabled, because all x86-64 processors support this extension.

bryanl · 12-26-2010, 12:45 PM

The E5400 Pentium appears to be a dual core 64 bit CPU (see Intel so that'd work if the mobo also supports 64 bit. Look up the specs and see - or just try to run the Ubuntu 64 bit version from CD or USB and see what happens.

As to whether you "should" or not, these kinds of things don't have that sort of requirement. Run what suits your needs. If you have some limitations in hardware or software requirements, then that will set your options. These days, with modern computers and systems, there really isn't any reason to stick with 32 bit versions - but then, for most, 64 bit versions don't really offer much advantage either. It is likely to take a while before the trend to 64 bit software starts to make anything 32 bit a backwards compatibility issue and the forward compatibility is, as johnsfine says, just about a moot issue.

But if you do heavy lifting with your PC (use Handbrake to convert your DVD library to mp4 for instance), you may find 64 bit provides an edge.

tronayne · 12-26-2010, 12:52 PM

You can use more than 4G RAM in a 32-bit system, but you'll probably need to recompile your kernel to do so; 64-bit systems can directly use RAM as you plug it in with no need to recompile.

Today, some common applications; e.g., Adobe Reader, GoogleEarth, only work with 32-bit systems but will work in a 64-bit system if the 32-bit libraries and some utilities are also present. While this is not trivial to do, it is doable (and some distributions -- I do not which -- provide both 64-bit and 32-bit libraries and utilities so you can both compile and use 32-bit applications on the same platform). This is a kind of gray area that seems to be in flux.

It is likely that 32-bit platforms are going to go away, being replaced by 64-bit. Not in the next few weeks, but certainly over the next year or two (or three or four). Many vendors already support both 32- and 64-bit distributions and there isn't much reason to doubt that they will continue to do so. That being said, you should evaluate your needs (rather than the needs of vendors and the latest-and-greatest crowd) and decide what you want to do; if you're going to replace your hardware soon, it might be better to go 64-bit (particularly if you use includes high-demand mathematics, CAD and other compute-intensive applications) -- bearing in mind that you might have to do without things like Acrobat Reader (there are PDF reader utilities provided with distributions) and GoogleEarth for a while.

Your 64-bit hardware will run fine with either a 32-bit or 64-bit distribution, but, what the heck, if you can do without some 32-bit-only proprietary applications, go for it.

Hope this helps some.

MrCode · 12-26-2010, 01:13 PM

I agree with most of the above. 64-bit is primarily good if you're doing lots of processing-intensive things (e.g. media encoding, code compiling, scientific applications, etc.), but it's not absolutely necessary, even if you have a 64-bit CPU. On a technical level the only real disadvantage is that the 64-bit extended registers never get used, so you a) can't directly address more than 4 GiB of RAM (although as has been mentioned this can be fixed [mostly] by enabling PAE in your kernel), and b) certain processing-intensive applications won't be as fast (bigger/more CPU registers = more numbers crunched at a time, at least theoretically, and again as has been mentioned most 64-bit applications have been built optimized specifically for 64-bit to take advantage of the extra/extended CPU features).

spoovy · 12-26-2010, 01:19 PM

Hmm I generally only use it for pretty basic stuff; I've never had a problem with speed and it's only got 2GB RAM.

I'll probly give the 64-bit version of slackware a spin next time round just to see how it performs, but it definately seems like there's no need to switch.

Cheers for the info chaps.

s2cuts · 12-29-2010, 12:14 AM

Spoovy, you don't sound like someone who needs to move to a 64 bit OS. 99.99999% of the software that you use doesn't even take full advantage of a 64 bit architecture. Don't believe me? Dual boot 32 bit and 64 bit versions of any distro, then do whatever performance comparison testing you want. If you get a significant difference, I'll eat my keyboard.

That being said, I moved to a 64bit version of my distro.

TobiSGD · 12-29-2010, 12:28 AM

Quote:

Originally Posted by s2cuts

Spoovy, you don't sound like someone who needs to move to a 64 bit OS. 99.99999% of the software that you use doesn't even take full advantage of a 64 bit architecture. Don't believe me? Dual boot 32 bit and 64 bit versions of any distro, then do whatever performance comparison testing you want. If you get a significant difference, I'll eat my keyboard.

That being said, I moved to a 64bit version of my distro.

Then you should buy a new keyboard, and a good sauce for your old one. Try to compare the execution time of a 3D rendering, or encode a movie to a different format, and you will see the differences. Just for example.

s2cuts · 12-29-2010, 11:46 PM

Quote:

Originally Posted by TobiSGD

Then you should buy a new keyboard, and a good sauce for your old one. Try to compare the execution time of a 3D rendering, or encode a movie to a different format, and you will see the differences. Just for example.

Depends on if the software you're using was written for a 64 bit architecture or not. Most is just old 32 bit code, recompiled with a 64 bit compiler. In my experience with the couple of tools I've used to re-encode video, there has been no significant improvement in performance. Maybe 10 seconds over 5 minutes worth of crunching. Not worth mentioning.

TobiSGD · 12-30-2010, 12:09 AM

Ok, maybe you want to have a look at the encoding benchmarks here.
But besides that, you left out the 3D-rendering part, it will be significant faster, so go, eat your keyboard.

rob.rice · 12-30-2010, 03:38 PM

depends on your mobo if you have 64bit connections between the HDD controller,vido adpter and ram
GO FOR IT !

rob.rice · 12-30-2010, 03:49 PM

Quote:

Originally Posted by s2cuts

Depends on if the software you're using was written for a 64 bit architecture or not. Most is just old 32 bit code, recompiled with a 64 bit compiler. In my experience with the couple of tools I've used to re-encode video, there has been no significant improvement in performance. Maybe 10 seconds over 5 minutes worth of crunching. Not worth mentioning.

only assembly can be written for one CPU or another
the latest versions of gcc have full support for 64bit regardless of whether there compiled to run on 32bit or 64bit

the same source code (except for small parts of the kernel and compiler back ends) are used on all linux systems from cell phones to main frames