"Poor" man's NAS

[Michael Hipp]

> From: "Alma J Wetzker" <almaw at ieee.org>
> Michael Hipp wrote:
> >> From: "Dominic Lepiane" <archangel at nibble.bz>
> >> To: "Linux tips and tricks" <linux-users at linux-sxs.org>
> >> Subject: "Poor" man's NAS
> >> Date: Thu, 8 Jun 2006 11:14:58 -0700
> >>
> >>
> >> Say a fellow wanted to get a multi-TB network file server running for under
> >> 10k, preferably close to 3k, what have folks here tried for large file
> >> servers on mostly commodity hardware?
> >>
> >> I was looking at one of my local PC retailers and I think I can get:
> >>
> >> Promise 8 SATA channel RAID card (PCI-Express x4)
> >> 8x 320GB SATA drives
> >> 8x Promise SATA hot-swap drive bays
> >
> >
> > Are SATA drives now considered to be "server quality". Conventional wisdom 
> > is that only SCSI is good enough for "real" production servers.
> >
> > Opinions?
> >
> > I need to build a server somewhat like you're spec'ing so the question 
> > isn't just academic. And the price of even one TB of SCSI makes me feel 
> > faint.
> 
> Opinion?  I got one of them things...
> 
> I really doubt that the media and heads are any different between SCSI
> and IDE (That really is the choice, even though both now have serial
> options and speeds have improved.)  Is the rest of the drive different?
>    I don't know.
> 
> The electronics, that I understand.  SCSI is still smart.  IDE is still
> rather stupid.  (IDE includes ATA and SATA)  IDE drives have all the
> useful stuff built into the controller.  The only do exactly what they
> are told, and only in that order.  SCSI, OTOH, takes all the commands,
> evaluates them and does them in the order that optimizes returning
> results based on what the drive mechanics need to do.  The performance
> difference is noticeable.

I was under the impression that SATA was more like SCSI than good ol' PATA.

The other side of the equation is in the CPU. I've seen charts of cpu load under heavy data transfer for IDE vs SCSI. The difference was dramatic (several x). (It gave the impression that IDE was a lot like a winmodem - all the real work done by the host cpu.) But again I had the impression that SATA was much more like SCSI in this regard.

Michael