Altos 5000
Dick Dunn
rcd at ico.isc.com
Thu Aug 23 03:17:00 AEST 1990
ti at altos86.Altos.COM (Ti Kan) responds to a flame-ette from Foulk about the
Altos 5000...
> ...On the other hand, when you think 386-ATbus
> boxes you are still thinking "Personal Computer"...
Not necessarily. We use AT-bus machines for most of our "server" roles,
and they work just fine. In fact, with fast disks and a good file system
(like ours:-) the performance is quite good.
> Perhaps I am going to sound like I am plugging our systems,...
[followed by ~ 100 lines of "plugs"]
Yes, you do sound that way, but let's just take it as an invitation to a
"critical examination" of your claims.
> Our Altos 5000 supports 200 users. What serial port card out there
> with a "standard" SCO driver can support such a requirement?...
This is nonsense. "Supporting" a user is very much more than allowing a
terminal to be plugged in. Quite simply put, it doesn't matter whether you
can handle the I/O connections or even the I/O bandwidth; you don't have
the CPU power to support 200 people actually *using* the system.
On terminal boards - it's good that you've got some intelligence out on the
boards, since interrupt handling is one of the weak points of the 386/486,
but that's really nothing particularly unusual. (Even my modem's got a
68000 in it.)
> We chose to integrate many functions onto a single "Base I/O card"
> card, which is shipped with every System 5000. This card has a floppy
> controller, a SCSI hard disk controller, two RS232 serial ports
> (corresponding to COM1 and COM2 for compatibility), a parallel port
> (again, corresponds to LPT1 for compatibility), and an ethernet port.
Many (most?) *motherboards* nowadays have the floppy, 2 serial, parallel
built in. They also have IDE, which is a good "base" disk interface.
So you're up a little from that, since you're spending one slot instead of
the two (SCSI, net) that a vanilla machine would take.
> ...With the largest currently supported SCSI disk at 1GB
> per disk, the System 5000 can have up to 30GB of total disk space...
Total expansion capacity is a useful number to look at to be sure it's not
too small, but mostly it's a red herring. Again, you're going to run out
of CPU power long before you run out of disk, if your users are doing
anything serious.
> To further improve disk performance and reliability, we offer disk
> striping and disk mirroring. The parallel seeks of disk striping
> decrease average seek time and the redundancy of disk mirroring
> provides a measure of data security that is quite necessary in a
> large system...
Disk striping is truly useful, but disk mirroring is mostly a pawn in the
feature game. It takes substantially more I/O bandwidth to do the double
output, and it doubles the cost of disk storage. Why not spend only a few
bucks extra and buy reliable disks?
> You see, when we built the System 5000 we aimed very high. This
> system is so capable that we position it as a mini-computer, among
> the ranks of Pyramids and Sequents...
People are using standard 386 and 486 machines as mini-computers, like it
or not.
>...Yet we priced it reasonably,
> that it is in the same league as the "PCs", such as Compaq Systempro
> and the HP Vectra.
Let's get down to some real numbers here. We ought to look at the price:
performance in quantitative terms, not glowing generalities. I'm not
saying you're wrong; I'm saying you haven't told us anything on this
point.
> I think the Altos 5000 differs from other such 486 EISA boxes (which
> includes the Compaq and HP mentioned above, as well as a zillion other
> clones), precesely because we designed it, software and hardware,
> from the ground up to be a non-PC.
You're waving the term "PC" about like a red flag. What's the real issue?
Let's get *beyond* the name game. We often use "PC" to identify the bus
structure, or to denote a *86-based machine, but they're used for all sorts
of stuff...not just "sitting on a desk, plunking away DOS-like."
What I see, overall, is that you've got a fairly capable, quite expandable
486 EISA machine. I don't see anything qualitatively different about it.
> See the review of the System 5000 in the July issue of _UNIX WORLD_...
_UNIX_World_?? Oh, yeah...isn't that the magazine that just carried an
article about UNIX-based BBSes without a single word about either USENET or
ARPANET? I think you need a stronger source of review than that.
--
Dick Dunn rcd at ico.isc.com -or- ico!rcd Boulder, CO (303)449-2870
...I'm not cynical - just experienced.
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