[Sussex] A funny thing happened on the way to the Net

[Steve Dobson]

Dominic

On Thu, Dec 15, 2005 at 11:08:09AM -0600, Dominic Humphries wrote:
> Quoting Steve Dobson <steve at dobson.org>:
> 
> >What surprised me the most was Gentoo's showing. . . Gentoo is
> >a distro that I think as targeted at developers, or people who
> >want access to (or close to) the cutting edge.
> 
> I don't know. I use Gentoo, and I'm neither a developer nor someone who 
> wants cutting edge. I just like the portage system & the community
> support you get with Gentoo.
> 
> And IME, Gentoo's out-of-the-box settings are nowhere near cutting 
> edge: I still haven't got the option of upgrading to Firefox 1.5,
> for instance. NVU, the HTML editor I use when I can't be bothered
> to use a text editor, is still sitting at 0.9 despite 1.0 being
> released in June. And so on.
> 
> To get cutting-edge, you've got to deliberately tell it to use unstable
> releases: On defaults, it will only install software that's been pretty
> well-tested.

Then I have to ask what is the point of Gentoo?  If you get the same
software as Debian/sid or Fedora then why were you paying the compile
time costs that Gentoo requires.

To answer my own question:  Because Gentoo does offer and advantage
to you over the other options.

As for as my original post was concerned it didn't matter what the 
difference was so long as there was one.  Red Hat and Debian are
(ignoring the commercial side) basicly the same beast:

   * Both are binary package distributions, and
   * Both do a lot of testing between releases.

I am trying to explore how the differences between the various Linux
distros are good for business rather than the differences themselves.
Microsoft has one OS for all your computing needs (the different editions
are more for marketing than for any technical differences between the
systems), a one size fits all approach.

In Linuxland you get choice, some times to much choice for the newcomer.
There are distros targeted at the newcomer, some that a developed by
non-commercial communities, and others that are offering free community-
based support.  Everyone has said that choice is good, but how it it
good?

> I must admit that sysadmin-ing a web host isn't something I know much 
> about, but I believe Debian packages are optimised for 386, while Gentoo
> optimizes for whatever CPU you actually have - possibly sysadmins are
> thinking that if they spend a fortune getting heavy-hitting CPUs, they
> might as well use a distro that makes maximum use of them?

I would doubt that is the case.  I think it was in 1972 that the human
costs overtook the hardware costs in computing.  Today it will only 
cost you a few hundred pounds to buy a system that could run the software
50% fast than the box it is running on at the moment.  That's a zero 
risk option - and if the system isn't available today tomorrow it will.

Optimizing code is a black art, and there are some really non-obvious
settings that need to be applied.  One from my past (years ago using
Sun SPARCs) was in the use of CPU caches.  Caches have to be good for
your programs right.  A little bit of memory in the CPU chip that has a
CPU/Cache bus that runs at 10+ times the speed of the CPU/memory bus
can only do you good right?

Wrong!

It turned out that the cost of a CPU cache miss on those SPARC stations
were quite expensive, and if your application had a large memory address
range (ours did) then those costs added up and it was better for some
application to run cache-less.

Believe me, there is so, so much more to performance tuning then just setting
a few switches on the compiler.

Steve
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