[KLUG Members] Re: REDHAT: My suggestion on organizing binary CDs for x86 chip-specific optimizations

[Adam Williams]

>>>I think it'd be a good idea for a startup (like how Mandrake started),
>>>offering CPU optimized Redhat distributions.  I've thought about it...
>>I think it would serve RedHat well to do it itself.

Redhat has to make money *someday*.  I can't see how maintaining more CDs 
would accomplish that.  And the problem with doing something like this as 
a LUG project is that slinging around ISOs takes bandwidth, bandwidth, 
bandwidth.....

>Agree, but if Redhat doesn't, there is an opportunity there IMO. > 
>>> If nobody is going to buy these optimized CD's from KLUG, it's not worth
>>> the hassle.  That's the bottom line for me.  Nobody is buying my SGI CD,
>>> so it won't be offered for 7.3/8.0 and beyond.

That's ok,  I'll provide the SGI CD if anyone asks really nicely.  
Hopefully RedHat will support XFS someday.  They sell an "enterprise" 
version that doesn't support ACLs..... go figure.

>>But it would be nice to have them as an option from RedHat.  God knows
>>I'd download and distribute the i586/686 and Athlon/x86-64 CD #1s
>>_instead_ of the i386 "Default" ones.
>Heck yes!!!  If that ever happens, you guys running junk hardware are
>going to be out of luck when it comes to BSware!!!   :-)
>>>Is that Mandrake's numbers?  I take them with a grain of salt.
>>>"_up_to_30%" can also mean 1% or less.

Thank you.  This is a very important point about benchmarks.  The *VAST* 
majority of them aren't worth a warm pile of dung.
  
>>Well, it's Intel in general. 
>With Redhat, it's running a "mix" with dynamic binaries (most programs)
>since they have i686 optimized glibc files and CPU specific kernels.  

"Most" programs spend "most" of there time inside glibc,  so this pays off 
quite well.  And most people (IMHO) don't use CPU intensive applications.  

However!  Tuning can effect cache utilization (page alignment, blah blah 
blah) which can make a noticeable diffrence.

Optimizing other libraries as well can make a nice difference.  gdbm if 
you use OpenLDAP is a nice one (lots of hash table stuff, etc...).  Squid 
also benefits nicely from optimization.  But I'm really suspicious of 
claims of over ~20% improvement.   One usually rams into other barriers 
before you can cross the 20% mark.

These optimizations are pretty easily achieved by tweaking the spec files 
of source rpms.
 
>I wonder how what the gain would be compiling the rest of binaries with
>CPU specific optimization?
>>>I'm not going to do it for myself, but I might be talked into doing it
>>>if there is enough interest.

My primary workstation is still a lowly PII (dual) and will be for the 
forseeable future.  My servers are highly customized.  So count me out on 
buying one.  I'd want the "generic" CD so I can install it anywhere.