[ltp] Ubuntu 32 vrs 64 bit

[Micha Feigin]

On Mon, 15 Dec 2008 13:35:51 +0000
"Daniel Castro" <castromd@tcd.ie> wrote:

> Hello hello,
> 
> I have a T61 with the Intel Core Duo 2GHz, 2GHz of Ram, Intel video 14.1,
> Atheros wifi.
> I have been on Ubuntu since 7.04, and always running the 64 bit versions. On
> previous versions, (previous to 8.04) setting up some programs was a bit of
> a pain in the behind (java, flash), but I find that after 8.04 everything
> runs just fine.
> I am about to format and reinstall 8.10 (I like clean installations not
> upgrades...) but I'm wondering if there is really a significant difference
> between running 32 or 64 bit. I'm running 8.10 on my T61p at work and on
> some other laptops in the lab and it runs just fine as well. I couldn't tell
> the difference.
> >From reading forums and stuff it seems like the majority of people agrees
> that the performance improvement of running 64 bit is not that much unless

Actually, for most uses you actually get a performance degradation and not
performance improvement. It's true that you have more registers and a longer
word, but unless you use data intensive programs that know how to employ vector
calculations you will actually see performance degradation (or no change).

This is due partly to the fact that you have larger pointers and data types and
your programs are thus consuming more memory in 64bit mode.

> you have more than 4GHz of RAM (don't ask me why...), and that software

If you want to use more than 2GB ram that yes, you will need a 64 bit system
(actually with appropriate kernel configuration you can make a 32bit system use
3GB of ram, but without kernel configuration, possible patching and
recompilation you will only see 2GB of ram).

> support is much better on 32 bit.
> What do people in this list say? Be cool and hard core with 64 bit or be
> conservative and safe with 32 bit?
> 

If you format and reinstall anyway on each upgrade I would go with a 32bit
system this time and on the next upgrade if you also install more memory you
can migrate back to 64bit system.

> Cheers!
>