Deciding which architecture: amd64 or x86?

[therisen]

Hello folks,

i'm currently using debian testing (etch) and i'm planning to check out gentoo in order to get a deeper understanding of how linux actually works and because of fun aspects

However I'll have to make a rather important decision before installing gentoo - which architecture? My cpu is an amd64 so basically one should use the amd64 architecture of gentoo. I've read that it is much harder to get such a system to run smoothly than a x86 (especially hardware issues). So the alternative would be to use x86 architecture (which I'm currently using with debian). Nevertheless I think that this is a contradiction to gentoo's philosophy of building and optimizing each software for its specific architecture/system, isn't it? Or are the speed differences not significant?
I'd appreciate some advice on that issue Thanks in advance.

Greets, therisen
_________________
"Pure mathematics is on the whole distinctly more useful than applied.
For what is useful above all is technique, and mathematical technique
is taught mainly through pure mathematics.

Godfrey H. Hardy

[prymitive]

I was using amd64 for few months and I switched back to x86. For me there were no big performance gains, nothing that You notice right away, only much less free memory, that's becouse not all my apps are 64 bits (opera, mplayer-bin if You want to play wmv, enemy territory, firefox-bin over firefox if You want flash) and many libraries were loaded twice for 64bit apps and for 32bit ones. I don't do any media transcoding, povray or any other tasks that can profit from 64 bits.
I've got 512MB of ram and under x86 swap is almost never used, under amd64 I had much bigger memory usage, all I needed was to run enemy territory and my swap was getting filled with 30-50 MB. I can buy more ram, sure, it will stop amd64 from using swap, but when I add ram and stay with x86 I will profit even more becouse I will have a even more free memory.

[luker0]

I've got an amd64 install and I have almost everything working. I'm starting to regret not going x86 though. It was just plain easier to get an x86 system running as a multimedia capable workstation. That plus I can print to my laser printer under x86, I haven't figured out how yet on amd64.

Performance wise, my wife's almost identical amd64 based machine running Winblows seems about as fast as my gentoo system. Some web based (flash and shockwave) things actually run slower on mine.
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Gentoo Machines I use:
AMD 3200, Asus A8V-Deluxe, Matrox G450 dual head - main workstation
AMD Athlon XP 1700+, Biostar M7VIG 400, MSI FX5200-TD128LF - MythTV box
Intel P3 1.0Ghz, Asus TUV - File, LDAP and web internal server

[therisen]

Thanks a lot luker0 and prymitive, your answers are exactly what I was looking for

If installing the x86 arch on an AMD64, what CFLAGS do you actually set? Is it http://gentoo-wiki.com/Safe_Cflags#Opteron.2FAthlon64_.28AMD.29 (32-Bit version)?
_________________
"Pure mathematics is on the whole distinctly more useful than applied.
For what is useful above all is technique, and mathematical technique
is taught mainly through pure mathematics.

Godfrey H. Hardy

[prymitive]