[CentOS] CentOS on Compaq Proliant Rackmount Servers

Mon Jul 18 23:15:10 UTC 2005
Bryan J. Smith <b.j.smith@ieee.org> <thebs413 at earthlink.net>

From: John Hinton <webmaster at ew3d.com>
> Yup, it's a shame to waste expensive horsepower if you don't need it and 
> most web stuff doesn't use a lot of horsepower.. Buy a bit above your 
> needs. Quality over horsepower as well, has been my philosophy.

Actually, it's not about waste IMHO.  It's about believing a newer
processor design means the interconnect is better.

A dual-P3 on a ServerSet IIIHE-SL will slap a P4-Celeron silly when it
comes to server I/O.  Especially when you throw a GbE on one PCI
channel, and your SATA RAID on another.

> I would advise going to the DL380 series. These use only the ultra2
> or 3 scsi drives.. not the mix of ultra and wide-ultra.

Actually, it wasn't until recently that most 36, 73, 146GB SCSI drives
started breaking 40MBps sustained.  Ultra2/3 (aka Ultra80/160) offer
LVD (low-voltate differential) for longer bus length and integrity.
But yes, at today's disk speeds, Ultra2(80) is minimum.  And you
typically don't want more than 2-3 drives per channel.

Although Ultra640 is planned, Serial Attached SCSI (SAS) is going to
quickly kill it.  A parallel storage bus is yesteryear.  Until then,
a SATA controller with queuing and "enterprise" SATA drives is the
best of all worlds.  The great thing is that SAS can use SATA drives
too (so you can recycle your "enterprise" SATA drive investments).

> I very nice speed improvement. Also, when buying, watch for drives
> quanity, size and speed (try to avoid the 7200rpm and get the 10 or
> 15k units).

Because in many cases, many current 7200rpm drives come off the
same line as ATA and SATA drives too.  Interface is not an indicator
of reliability, the actual mechanics are.  A good indicator is the
vibration and other tolerances in the spec sheet.  "Enterprise" drives
(typically the 9, 18, 36, 73 and 146GB capacities) vibrate 3-8x less
than "Commodity" drives (typically the 40, 80, 120, 160, 200, 250,
300, 320 and 400GB capacities).

E.g., WD Raptor 73 and 146GB 10,000rpm SATA drives come off the
same line as Hitachi 10,000 U320 SCSI drives.

> I think that was the ending point for the 1850s. The DL380s are almost 
> the same unit with a lot of parts being interchangable. The 380s are 
> just more modern in terms of processors, circuitry, raids, drives... and 
> pretty much picked up I think at the 600mhtz point and have grown from 
> there. The dual 866s and up to about 1.2 giggers are very reasonble on ebay

>From what I was reading, the 1850 and similar era are 440 and 450 series
chipsets.  The 440 is _crap_.  The 450NX is so-so, but bridges on extra PCI
channels (for either 2 or 5 total).  It still doesn't compare to a ServerWorks
ServerSet III series.

> A t-1 is still only 1/6th of a ten base ethernet card... and how much 
> power does it take to deliver products at one sixth of a 10base card? 
> Yeah, I know.... it's more complex than that. Database apps can eat up a 
> lot, email/spam systems can eat up HUGE amounts of processing power. But 
> if you're mostly delivering web pages, it just doesn't take much.

I guess I've been too used to having a GbE saturated.  ;->



--
Bryan J. Smith   mailto:b.j.smith at ieee.org