[BlueOnyx:13583] Re: BlueOnyx:13368] (Mac's reply 1) Re: What is the minimum & ideal PC specification ?

[Michael Stauber]

Hi Mac,

I'm a bit slow to respond to this, so it may be mostly for the archives.

> * Architecture:
>  
> a: Supports x86 Systems (32-bit Pentium, AMD, Via) (and note says:
> non-PAE capable CPUs not supported)
>  Q: So how do I find out if my particular P3 (or any other) is 'PAE
> capable' ?

Easiest way is to boot off the BlueOnyx CD. Use the boot menu to start
the rescue mode if you don't want to install anything yet. See if it
boots. If it does and you eventually get a command prompt, type ...

cat /proc/cpuinfo |grep pae

Among the listed "flags" it should show "pae".

> b: Supports x86_64 systems (AMD64/EM64T)
>  Q: So it doesn't support a Pentium 64 bit ?
>  Q: And what about duel-core Pentiums ?

It does support AMD and Intel CPU's with 32 bit (BlueOnyx 5106R and
5107R) and 64 bit (BlueOnyx 5108R) with one or more cores. However, both
manufacturers have created a lot of CPU's of which not all are 64 bit
capable.

For example: Pentium 4s are only 32bit compatable. The first 64bit CPU
from Intel was a Pentium 4 on LGA 775 (Prescott core, marked by a F such
as Pentium 4 3.0F). Which sometimes adds a bit to the confusion as to
which older hardware can really run a 64 bit OS.

> * Minimum disk space: 2GB
>  Q: So why does the BO-install menu have a choice for installs with less
> than 20GB ?

A more or less "virgin" install of BlueOnyx off our install CD will use
around 4GB of space on the disks for the OS. BlueOnyx also creates a 2GB
Swap partition. 1GB of Swap if you choose the "install on disks <20GB".

So all in all that's already 5-6GB used. Which gives you (assuming 20GB
of diskspace) roughly 14GB of space for logfiles, temporary data (like
YUM updates), emails, sites and users. In our experience that already
cuts things rather short. It's not uncommon that a server gathers around
5-10 GB of logs after a while that it's been running. And you never,
never ever want a Linux box to run out of diskspace, as that will trash
the OS to a point where it might refuse to even boot.

The specs on the CentOS page may say 2GB are sufficient. But that's only
the case for a bare minimum install without KDE or Gnome, next to no
Swap partition, no logs and no data. Such a minimum Linux install is
usable for some purposes, but not as a general purpose webserver such as
BlueOnyx.

> * x86 (ram?): 392M CLI/512M GUI per logical CPU
>  Q: so min ram is 392M ?
>     Q: so what does CLI/512M mean ?

CLI = Command Line Interface. Means: No graphical desktop. 512MB (or
less than that) is nothing these days. Especially 64 bit applications
and daemons are memory hungry. Just fire up Apache and even if it idles
it'll use up your 256MB easily. A Linux that runs out of memory will
start to use Swap. Which directly creates a performance hit, as access
to Swap memory on the hardisk is a lot less rapid than direct access to RAM.

> Q: if the minimum ram is 392MB, how can it run with only 64MB RAM ?
>      but not with my 'massive 256MB' ?

That question makes no sense or I at least I don't understand it. Now
"can run" and "will run well" are two different sides of the same coin.
Personally I wouldn't run any server with less than 1GB of RAM for any
purpose whatsoever. This is not the 90's anymore and RAM is cheap.

Sure, I like to re-use old hardware as well. But maybe not *that* old.
If the hardware is maxed out with 512MB of RAM, then perhaps it's just a
piece of junk and not worth using it anymore for purposes such as this.
I certainly wouldn't bother it with a modern 64 bit OS  - even *if* the
hardware could run it.

You can get a new desktop PC for around 300 EUR off the usual retailers
or in well stocked super markets. Something like an Intel i3 with 4GB
RAM and a 500GB SATA disk. It won't be a stellar performer compared to
"real" server hardware that's around these days, but it will still beat
that old legacy hardware six ways 'til Sunday and BlueOnyx will run very
well on that.

Or there is the option to grab some used kit off Ebay or elsewhere.

The most minimal specs that any BlueOnyx will run on really wary
depending on the version of BlueOnyx, the expected usage cases and the
patience of the user that deals with that hardware. A BlueOnyx 5106R
might run on a box with 256MB of RAM, but don't ask me to troubleshoot
it, as I won't have the patience to wait for it to finish swapping every
time I try to use the tabulator key to auto-complete a shell command. :p

Therefore I'd say: Minimum specs for 5106R/5107R? Intel Celeron CPU (or
similar AMD), 1 GB RAM, 20GB disks. For 5108R? Intel i3 CPU, similar AMD
or better. For 5108R 1GB RAM already cuts it short and I'd rather give a
64 bit box some oodles of RAM extra. It makes no sense to build a
highway that has speed bumps every hundred meters. These days a server
ought to have 2, 4 or 8GB depending on the expected usage experience.

Less is always possible, but we don't want to say "it's fine" on kit
that ultimately gives you a sub par experience.

The subject of this message also asks about the "idea" specifications.
Here is what I consider ideal for a box that will perform well even
under adverse conditions:

Intel i5 CPU, 8-16GB of RAM, 2x 500GB or 2x 1TB SATA disks. Throw in a
dedicated SATA RAID controller for best performance.

With 8GB RAM an no dedicated SATA RAID controller kit like that can be
grabbed new for around 500 EUR (assuming it's a desktop unit). If it
needs to be a 19" unit, it'll cost around 750 EUR depending on specs. 1U
is not always the best choice, as modern CPU's need more cooling than
you can get in a 1U chassis. 2U allows for more flexibility hardware
wise and allows better cooling.

Now we said "ideal". If we really mean "really ideal", we're probably
talking Xeon CPU's, SAS disks with a dedicated controller or a dedicated
NAS that's connected via fibre channel. I have seen the big brother of
BlueOnyx (Aventurin{e}) run on boxes with 32 Xeon cores and around 148GB
of RAM. A single BlueOnyx won't max that out, but it'll run exceedingly
well on that kind of gear, too.

-- 
With best regards

Michael Stauber