Anyone have a DECstation 5810 or 5820?

[George Robbins]

In article <11917 at watcgl.waterloo.edu> idallen at watcgl.waterloo.edu (Ian! D. Allen [CGL]) writes:
> Anyone have stories about the 5810 or 5820 they want to share?
> We are thinking of replacing our VAX8600/4.3bsd with one.
> We were originally thinking of getting two DS5400's, but the low disk
> bandwidth of the 5400's would probably upset us.

Well, I don't have one yet, but I have an order for a 5810 pending management
approval and had to go thru some of the same mental excercises.

The 5400 has a fair amount of bandwidth, but loses cause it has a limit
on the number of drives you can attach and there is *no* way to attach
a real tape drive!  (TA/TU78).
 
> Each controller is in its own Unibus adapter.  I'm trying to decide
> whether to keep the disks or upgrade to RA70's or RA90's or maybe get
> two RA90's and use the two RA82's or...  And there's the whole thing
> about do I really want a few big and fast disks (RA90) or a bunch of
> small but slower ones with more seek overlap (RA70), and should I put
> all four disks on the one KDB50 controller or should I really buy
> another, or several others..

I opted for the configuration with 2 RA70's built in, for little root, /usr
and /tmp drives and plan to pick up a used HSC50, mainly so I can share a
couple of TA78's with our VMS systems.  I have some of CDC Sabre 1.2 G-byte
drives that I hope to attach to either the KDB50 or the HSC (whichever works
better) via 3-rd party SMD adapters.  The RA90's look nice but I already
have the Sabre drives, also rumor has it that the KDB50 has considerably
better performance than the UDA50...

> And can anyone explain DEC's pricing on this thing?  As I understand it,
> a single-cpu VAX6000 machine with the same memory and disk costs the same
> as or more than the DS5810, but the 5810 runs at four times the cpu speed.

They were getting blown out of the price/performance water by the competition
and splitting the price maintains margins on the captive VMS customer base...
-- 
George Robbins - now working for,	uucp: {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing	arpa: cbmvax!grr at uunet.uu.net
Commodore, Engineering Department	fone: 215-431-9255 (only by moonlite)