[lug] More Server Problems

[Sean Reifschneider]

On Wed, Feb 22, 2006 at 03:58:02PM -0700, George Sexton wrote:
>My working theory is that the problem with my existing machine is that there
>is a bug in the kernel's 64-bit software RAID or ReiserFS code. Since I

I have had problems with running Opteron systems in 32-bit mode, problems
like I can't even install because the network driver doesn't work...  The
Intel EM64T boxes I've run seem to work in both 32 and 64 bit modes just
fine.

So, while a lot of people seem to think that AMD having the 64-bit CPUs out
first meant they were more innovative, my general impression has been that
Intel was just spending time to make it more stable.

>calendar, I'm thinking I'll be able to run something like 500 virtual hosts
>a machine with 2GB of RAM. If I can get 64 bit boxes with 16 GB of ram then
>I would be able to run something like 4000 or so customers on one machine.

Those rarely make sense unless you REALLY need the big-arse box.  Which it
doesn't sound like you do, you aren't working with any single 16GB
data-sets, etc...

These sorts of boxes usually start at $15k and go up pretty quickly from
there.  If it's your only box, what are you going to do for your clients to
ensure availability?  Spent the big dough on the 4 hour on-site support and
field the calls the 4, 6, 8, or more hours until they've fixed it?  Buy
another cold spare box, doubling the price?

For that same $15k you can get 17 1U lower-end machines, with a total of
16GB or even 32GB of total memory, *AND* have a cold spare, plus reduce
your exposure for any single failure (impacting only 1 16th of your
clients, instead of all of them).  Also, you can grow it incrementally, as
sales dictate, instead of having to spend the $15k or more up front and
then find the clients.

There are reasons for these massive machines, but these days they're pretty
few.  Works well for guys like Wikipedia, slashdot, etc...

Thanks,
Sean
-- 
 "When men are pure, laws are useless; when men are corrupt, laws are
 broken."  -- Benjamin Disraeli
Sean Reifschneider, Member of Technical Staff <jafo at tummy.com>
tummy.com, ltd. - Linux Consulting since 1995: Ask me about High Availability