RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?

["Julian Satran" <Julian_Satran@il.ibm.com>]

Bob,

I think that we where referring to a
different environment that uses 100Mb/s for home and can connect some old
or new disks to some "older PC's" and get inexpensive arrays
that can be shared.

Julo

Robert Snively <rsnively@Brocade.COM>
Sent by: owner-ips@ece.cmu.edu

15/04/03 05:52

To	Julian Satran/Haifa/IBM@IBMIL, Robert Snively <rsnively@Brocade.COM>
cc	ips@ece.cmu.edu, owner-ips@ece.cmu.edu, Russell Lewis/Tucson/IBM@IBMUS
Subject	RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?

Julian,
 
The stated environment was a diskless
home system with disks remote.
 
Home system means broadband attachment
at less than 1.5 Mb/sec from
the home to the remote iSCSI device,
so it really doesn't matter how
fast your local connection is
(10 Mb/s or 100 Mb/s, you only get 1.5 Mb/s max)
 
Been there, done that, it is not
so hot, unless system, swap, and 
program are local, meaning not
diskless.  Dataless with NFS works
okay, because all the operational
functions run locally and only file
access runs remotely, and that
does not require iSCSI (and in fact works better
without iSCSI for comparable technology).
 
The stated environment was legacy,
which means there is no administrative
tool or specialized file system
to allow the use of shared remote storage.
 
I absolutely agree that native
SCSI disks will perform better than IDE disks attached
via local or remote iSCSI.
 
Bob
-----Original Message-----
From: Julian Satran [mailto:Julian_Satran@il.ibm.com]
Sent: Monday, April 14, 2003 4:36 PM
To: Robert Snively
Cc: ips@ece.cmu.edu; owner-ips@ece.cmu.edu; 'Russell Lewis'
Subject: RE: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?


Bob, 

I wonder if your opinion is based on real experience or prejudice.
Our measurements indicate that an inexpensive box with SCSI disks performs
BETTER than an IDE (typical) desktop drive 
using iSCSI over a 100MB/s connection (widely available for home use) -
and that includes paging (usually marginal) and all the rest.

        Julo

Robert Snively <rsnively@Brocade.COM>
Sent by: owner-ips@ece.cmu.edu

14/04/03 18:06

To	Russell Lewis/Tucson/IBM@IBMUS, ips@ece.cmu.edu
cc
Subject	RE: Are there any coming iSCSI HBAs?  Preferably at 100Mb speed?

My experience with diskless workstations is that 
they are limited by paging activity and background
updating to really unacceptable performance, even in
simple word-processing programs like frame maker 
doing medium sized books, and even on a local 10 Mb/s
network.

You are far better off running a workstation with
a local disk for system and swap, but running
dataless.  NFS or comparable networking programs
run fine for that.  The local caching of the files
on disk and in memory assure adequate performance, while
the maintenance of your data remotely assures
appropriate centralized data management and backup.

Remember too, that it is a rare broadband connection
that gives you anything approaching 100 Mb/s.  A T1 DSL link
is specified at 1.54 Mb/s, and it is the fastest of the
common broadband links.

In addition, there is nothing more frustrating than being
unable to operate because your link is down or severely
congested, something that happens far more often than the
unavailability of a local disk.

My view?  iSCSI is not an appropriate protocol for home
networking data access.  Use your IDE or SATA drive locally
for boot, swap, system, and any hot programs and use
NFS or other remote file access program against a remote
server for data and other programs.

Bob Snively
408-333-8135
rsnively@brocade.com

> -----Original Message-----
> From: Russell Lewis [mailto:russelll@us.ibm.com]
> Sent: Friday, April 11, 2003 9:25 AM
> To: ips@ece.cmu.edu
> Subject: Are there any coming iSCSI HBAs? Preferably at 100Mb speed?
>
>
>
>
>
>
> Does anybody know of any current or coming iSCSI HBAs which
> show up (to the
> BIOS) as ordinary SCSI adapters?  I'd like to drop such an HBA into a
> legacy computer and run a totally diskless workstation at home.
>
> However, since it will be a home computer, I'm willing to
> operate at 100Mb
> speed - I'm willing to eat the performance hit.  It seems to me that
> somebody could make an iSCSI HBA with a 100Mb interface and make it
> affordable for the home user (say, $50-$100).  Anybody know
> of such plans?
>
>