Very Computer

Greetings:

It seems that most folks are interested in SATA for RAID servers.  I
would like to build a high-performance computational workstation, thus I
plan to use Western Digital 10kRPM "Raptor" SATA drives.

As I understand, it isn't yet possible to install Linux directly to SATA
drives.  Or is it possible with newer 2.6.x kernels?  Even if not, I can
still benefit from having some of my filesystem located on the high
speed SATA drives.

In the past I built systems using AMD Athlon CPUs, for their superior
price/performance to Intel.  But now I think the Pentium 4 outperforms
the Athlon for similar price/clock levels?  I don't want to build an
Opteron system, because I don't want to spend time fussing with it to
make it work.  I have read about it and it seems people have struggled
to make it work.  Perhaps that is only with the 64-bit mode, but I just
don't want any headaches.  The point of this post is to research which
mobo offers the best performance balanced with nearly ideal (minimal)
installation and configuration effort.

I do not wish to build the most expensive workstation, but to build one
in the $1000 range (no monitor).  I have considered the Asus A7N8X with
Athlon, which also has the Sil3112A SATA controller, which I know is
supported.

Is there a better mobo, perhaps for the P4?

Thanks for input.

Good day!

--
____________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA

Quote:> Greetings:

> It seems that most folks are interested in SATA for RAID servers.  I
> would like to build a high-performance computational workstation, thus I
> plan to use Western Digital 10kRPM "Raptor" SATA drives.

if you setting up a server, why dont use scsi drive? linux have no problem
running a scsi device. anyway, is up to your budget.

Quote:> As I understand, it isn't yet possible to install Linux directly to SATA
> drives.  Or is it possible with newer 2.6.x kernels?  Even if not, I can
> still benefit from having some of my filesystem located on the high
> speed SATA drives.

im not sure which linux you are talking about, but i running fine with
Mandrake 10 for SATA support.

Quote:

> In the past I built systems using AMD Athlon CPUs, for their superior
> price/performance to Intel.  But now I think the Pentium 4 outperforms
> the Athlon for similar price/clock levels?  I don't want to build an
> Opteron system, because I don't want to spend time fussing with it to
> make it work.  I have read about it and it seems people have struggled
> to make it work.  Perhaps that is only with the 64-bit mode, but I just
> don't want any headaches.  The point of this post is to research which
> mobo offers the best performance balanced with nearly ideal (minimal)
> installation and configuration effort.

> I do not wish to build the most expensive workstation, but to build one
> in the $1000 range (no monitor).  I have considered the Asus A7N8X with
> Athlon, which also has the Sil3112A SATA controller, which I know is
> supported.

> Is there a better mobo, perhaps for the P4?

im using Asus P4P800 , P4 2.8c, geforce FX, seagate barracuda 120GB. i test
out with redhat 9 and seem having problem with SATA , graphic and sound
detection. Mandrake 10 setup everything without headaches for me.

The point of the Raptor drives is that they offer SCSI performance at an
IDE price.  And that is no joke.  What is a problem, is the OS support
for the SATA interface.

Quote:

>>As I understand, it isn't yet possible to install Linux directly to SATA
>>drives.  Or is it possible with newer 2.6.x kernels?  Even if not, I can
>>still benefit from having some of my filesystem located on the high
>>speed SATA drives.

> im not sure which linux you are talking about, but i running fine with
> Mandrake 10 for SATA support.

Is your SATA drive the *installation drive* ?  What kernel is it (2.6.2
right)?  If so, then that is great progress, compared to what I have
been reading in the past few months.

Quote:> im using Asus P4P800 , P4 2.8c, geforce FX, seagate barracuda 120GB. i test
> out with redhat 9 and seem having problem with SATA , graphic and sound
> detection. Mandrake 10 setup everything without headaches for me.

Thanks for the reply.  Good day!

--
____________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA

I've no personal experience yet, but I've researched it and will have some
experience in a week or so. In any event, it's my understanding that it is
possible to install directly to an SATA drive, but only if you use certain
SATA controllers and/or use certain distributions and/or are willing to
customize your installation disk. The following site has more in the way
of details:

http://linuxmafia.com/faq/Hardware/sata.html

Quote:> I have considered the Asus A7N8X with
> Athlon, which also has the Sil3112A SATA controller, which I know is
> supported.

My understanding of that controller is that there are two Linux drivers
for it:

- A driver found in the ATA section of the kernel configuration, which
  treats the controller like an ordinary parallel ATA controller.

- A driver that's part of the libata package, which is found in the SCSI
  low-level section. If you use this driver, the drives show up as SCSI
  devices (/dev/sda, etc.).

My understanding is that the first driver is pretty stable but the second
driver results in some crashes, and in fact is marked as broken in the
kernel source, so you've got to set the appropriate option to even see it.
(This is with the 2.6.3 kernel; I'm don't know which of these is available
in the 2.4.x kernels.) The Web site I mentioned earlier cites an e-mail
exchange on a Linux kernel mailing list concerning the relative speeds of
these drivers:

http://www.kerneltraffic.org/kernel-traffic/kt20031208_244.html#2

It looks like the SATA driver is substantially faster than the PATA
driver, but apparently there's a patch for the PATA driver that improves
its performance. That reference contains all I know about this, though, so
I can't really say any more. In particular, I don't know if the patch is
making its way to release in a regular kernel.

--

http://www.rodsbooks.com
Author of books on Linux, FreeBSD, and networking

You can use SATA drives with Linux. This done, you obviously can install
Linux to it. But it's not as easy as it sounds (although probably
something like Mandrake 10 will install fine on every SATA chipset you
throw at it).

The "libata" driver set provides you with nice SATA support. It is already
included on the 2.6 kernel series, and can be added as a patch to 2.4.

Quote:> I do not wish to build the most expensive workstation, but to build one in
> the $1000 range (no monitor).  I have considered the Asus A7N8X with
> Athlon, which also has the Sil3112A SATA controller, which I know is
> supported.

Sil3112 support kinda sucks ATM (google for libata, read the status page).
Personally i'm running off a ICH5 (by Intel) with a 2x120G Software Raid 0.
ICH5 happens to also be supporte without libata on 2.4, but libata is
much better.

Quote:> Is there a better mobo, perhaps for the P4?

My motherboard is a D865PERL but 875 ones are better from the performance
point of view. If you go for the P4, I'd get either an Intel or ASUS
motherboard, with an ICH5. Personally im running 2.4.23 + libata patch
right now.

If you need something else, do a search for my posts on groups.google.com
and you'll get the basics of Linux SATA explained in like 30 different
ways :)

[edit]

Quote:> If you need something else, do a search for my posts on groups.google.com
> and you'll get the basics of Linux SATA explained in like 30 different
> ways :)

Thanks Gonzalo!

--
____________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA

Well, yes, it is.  Whether you can (1) get by with an aging 2.4.x
installation kernel, (2) need a more-cutting-edge 2.4.x kernel, or
(3) need a 2.6.x installation kernel or (equivalently) a 2.4.x kernel
patched with the libata backport depends entirely on which SATA chipset
you'll be using.

If you're using a 3Ware Escalade 8xxx card, or an Adaptec AAR 24x0 card,
or a LSI Logic MegaRAID SATA 150-6 card, you have the widest possible
installation options.  With Intel ICH5/ICH5R/ICH6 chips, HighPoint SATA
chips, Promise SATA chips, Silicon Image 311x chips, or the VIA VT6420
chips, you have somewhat fewer options.  With Marvell, ServerWorks, or
SiS 964 chips, you'll have a serious challenge.

Details at "Serial ATA" on http://linuxmafia.com/kb/Hardware

Quote:> Or is it possible with newer 2.6.x kernels?

Using a 2.6.x kernel gives you automatic access to libata drivers, which
address drives on (certain particular) SATA chipsets via the kernel SCSI
layers.  This is A Good Thing, where possible.  The SCSI support code
that's leveraged thereby is high-performance and very well debugged.

Quote:> Even if not, I can still benefit from having some of my filesystem
> located on the high speed SATA drives.

SATA is nice, but it's not automatically high speed.  The theoretical
bus _ceiling_ gets raised to 150 MB/sec, but you are hard-pressed to
saturate even a 66 MB/sec conventional ATA/66 bus with even the fastest
IDE hard drives, on account of physical read limits.  Frankly, the most
immediate advantage is the ability to use thin data cables (without
violating ATA spec), thereby not impairing cooling in small system cases.
In the future, SATA's ability to do tagged command queueing is going to
help performance, but driver support in Linux doesn't yet exist for
that, even in libata.  For now, if you want TCQ, you have to use (real)
SCSI.

[Athlon vs. P4, snipped]

Quote:> I do not wish to build the most expensive workstation, but to build one
> in the $1000 range (no monitor).  I have considered the Asus A7N8X with
> Athlon, which also has the Sil3112A SATA controller, which I know is
> supported.

> Is there a better mobo, perhaps for the P4?

I recently helped my mother-in-law build a Celeron-based system using a
fairly impressive yet inexpensive ASUS motherboard that included Intel
ICH5 SATA.  (It also had a Promise chip for support of Promise's wacky
proprietary software RAID, but we ignored that.)

Whether you even care about who has the faster CPU support might depend
on what you'll be doing with the system.  A lot of people's Linux
workstations spend most of their time being I/O-bound rather than
CPU-bound -- but most people don't use their workstations for
CPU-intensive tasks.  Your mileage may well differ.

--
Cheers,                             * Contributing Editor, Linux Gazette *
Rick Moen                       -*- See the Linux Gazette in its new home: -*-

Well, yes and no.

Theoretically, SATA drives can do TCQ, a la SCSI -- as you say, given OS
support, which happens not to have been yet written for any of the
applicable Linux drivers.  But you suffer the usual ATA inability to
support disconnected operation -- rendered moot in a way by the SATA
spec dictating that there will be only one device per SATA chain.  So,
ATA's inability to have both drives on a chain active simultaneously
(disconnected operation) is mooted by SATA's inability to have a chain
at all.  ;->

Of course, what you do instead is have multiple SATA chains.  For
example, you could get a 3Ware Escalade 8xxx or Intel SRCS14L PCI card
and have _lots_ of SATA connectors, each snaking out to a single SATA hard
drive.  But that points out another fly in the ointment:  CPU load.
You want lots of SATA connectors?  Fine, the CPU has to play traffic cop
among them, to some degree.  (Good designs like 3Ware's mitigate this
effect to the extent possible -- at some cost in sticker price -- but
it's still there.)

Weren't you the one agonising over whether Athlon or P4 motherboards now
give better CPU performance?  You see my point, I hope:  I'm not saying
you shouldn't go with SATA/Raptor for your mass storage, just that it
will impair CPU performance somewhat.

And the fastest SATA hard drives spin at 10K RPM -- the aforementioned
WD Raptors.  This of course isn't SATA's fault:  It's a market
segmentation effect -- the same intensely irritating market effect that
has jacked up the price of SCSI drives, in recent years.

Personally, when I want to assemble a high-performance workstation, I
pick any decent motherboard -- like the ASUS Celeron one I mentioned
separately, and cram a nice, inexpensive LSI Logic SCSI PCI card in it.
Then, I shop around for a pair of 15k RPM SCSI drives.  That gives
simultaneously a really good, fast, reliable mass storage subsystem,
zero OS-support headaches, _and_ unimpaired CPU performance.  But then,
I care more about being bottlenecked on I/O than most people.  Pick your
poison.  ;->

--
Cheers,                             * Contributing Editor, Linux Gazette *
Rick Moen                       -*- See the Linux Gazette in its new home: -*-

I would look toward gigabit or abit motherboards, DFI Lan party
Is a awesome board for the money.