Gentoo Speed Increases (was Re: [linux] Fun with Ubuntu)

[Garrett Cooper]

    I just tried icc a bit and read some feedback from people and it's a 
pain in the neck to implement even though it's supposed to be gcc 
compliant...
    Failed on a vector loop before or something when compiling when gcc 
didn't >_<...
-Garrett

Andrew P. Becherer wrote:

>     I have heard that one way to really squeeze some performance out 
> of gentoo is to install the intel compiler (if you are using an intel 
> part). The install process is fairly straightforward, you do have to 
> get a license from intel. The license is free for non-commercial use. 
> After emerging the compiler and putting your license file in the 
> proper location you add a USE flag for the intel compiler. Not all 
> applications will benefit from the intel compiler. I understand that 
> media encoders and decoders among other applications will benefit from 
> use of the intel compiler.
>     I am not taking advantage of it currently as I only have one intel 
> part in my inventory and it does light duty as a firewall/router. I 
> have it on good authority from the president of the Tacoma LUG that 
> the intel compiler can result in dramatic speed increases with certain 
> applications, YMMV. Not to say I don't love GCC, my Motorola G4 would 
> be a paperweight without it.
>
> Setup instructions are here:
> http://gentoo-wiki.com/HOWTO_Setup_ICC
>
> On Mar 7, 2005, at 6:03 PM, Doug McLean wrote:
>
>> This is a good point.  It may simply not be worth the extra effort to 
>> squeeze out, say %5.  But I always hear about how 64-bit processors 
>> are revolutionary compared to 32-bit ones, and wanted to see this.  
>> The Athlon64 I have really is alot faster than my old computer, even 
>> with 32-bit windows.  I haven't had quite such luck with Linux 
>> though.  It always seems to still be a bit slow, though I haven't 
>> spent the time to find out why.  :p
>>
>> Phillip Garland wrote:
>>
>>> How much improvement does compiling for a specific CPU get you vs. 
>>> the standard compilation for the architecture? I seem to recall 
>>> hearing 20-30% for pentium vs. i386, but I don't think I've seen 
>>> numbers for more recent CPUs. I doubt most desktop and server usage 
>>> is cpu-limited enough for cpu-specific compilation to be worth it 
>>> for most people.
>>> ~Phillip
>>
>
> Andrew Becherer
>