28 Oct
2007
28 Oct
'07
9:08 p.m.
Turns out to be mostly Sun, but a bunch of other stuff as well. Much
test equipment (list to follow when I decide what I want to keep), and
assorted VME Sun boards (Sun-3 and Sun-4).
There's also many boards for a (can't remember the name, it starts with
"T" and is the ultra-high-reliability system that runs 2 or 4
processors in parallel. Think it's PA-RISC, but can't recall for sure).
I don't have them, but can pick them up tomorrow if anyones interested.
29 Oct
29 Oct
12:25 a.m.
On 29/10/07 05:08, "Scott Quinn" <compoobah at valleyimplants.com> wrote:
There's also many boards for a (can't remember
the name, it starts with
"T" and is the ultra-high-reliability system that runs 2 or 4
processors in parallel. Think it's PA-RISC, but can't recall for sure).
I don't have them, but can pick them up tomorrow if anyones interested.
Tandem?
--
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?
30 Oct
30 Oct
7:15 a.m.
On Oct 29, 2007, at 12:08 AM, Scott Quinn wrote:
There's also many boards for a (can't remember
the name, it starts
with "T" and is the ultra-high-reliability system that runs 2 or 4
processors in parallel. Think it's PA-RISC, but can't recall for
sure). I don't have them, but can pick them up tomorrow if anyones
interested.
Tandem? If so, those will almost definitely be MIPS processors.
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
7:19 a.m.
Dave McGuire wrote:
On Oct 29, 2007, at 12:08 AM, Scott Quinn wrote:
Refresh my memory how those worked? Two processors in lock-step? Three
processors in a voting quorum?
Peace... Sridhar
There's also many boards for a (can't
remember the name, it starts
with "T" and is the ultra-high-reliability system that runs 2 or 4
processors in parallel. Think it's PA-RISC, but can't recall for
sure). I don't have them, but can pick them up tomorrow if anyones
interested.
Tandem? If so, those will almost definitely be MIPS processors. 
8:35 a.m.
On 30 Oct 2007 at 10:19, Sridhar Ayengar wrote:
Refresh my memory how those worked? Two processors in
lock-step? Three
processors in a voting quorum?
Nothing that simple. Special software and hardware. As was driven
home to me by a Tandem engineer who was also a good friend, the term
of art used by Tandem is "Nonstop" not "Fault tolerant". A world of
difference between them. For a very good analysis, check out the
paper "Why Do Computers Stop and What Can Be Done About It?" by
Tandem's Jim Gray. It should be somewhere on the web, given its
importance. It describes in very eloquent terms, the Tandem
philosophy.
Cheers,
Chuck
9:09 a.m.
Chuck Guzis wrote:
On 30 Oct 2007 at 10:19, Sridhar Ayengar wrote:
For a very graphic example of that philosophy, consider this:
In mid-2004 I ran into a guy who works at HP/Austin. His team had
just finished a major project. They had just completed certification of
the first 10/100 ethernet driver for Non-Stop OS.
Doc Shipley
Refresh my memory how those worked? Two
processors in lock-step? Three
processors in a voting quorum?
Nothing that simple. Special software and hardware. As was driven
home to me by a Tandem engineer who was also a good friend, the term
of art used by Tandem is "Nonstop" not "Fault tolerant". A world of
difference between them. For a very good analysis, check out the
paper "Why Do Computers Stop and What Can Be Done About It?" by
Tandem's Jim Gray. It should be somewhere on the web, given its
importance. It describes in very eloquent terms, the Tandem
philosophy.
5:16 p.m.
On Oct 30, 2007, at 11:35 AM, Chuck Guzis wrote:
Actually at least one of their systems (I don't remember what it was
called) does use a voting scheme, according to my old friend (and
former employer, and DEC20 hacker) Doug Humphrey, who worked for Tandem
for many years.
-Dave
--
Dave McGuire
Port Charlotte, FL
Refresh my
memory how those worked? Two processors in lock-step?
Three
processors in a voting quorum?
Nothing that simple. Special software and hardware. As was driven
home to me by a Tandem engineer who was also a good friend, the term
of art used by Tandem is "Nonstop" not "Fault tolerant". A world of
difference between them. For a very good analysis, check out the
paper "Why Do Computers Stop and What Can Be Done About It?" by
Tandem's Jim Gray. It should be somewhere on the web, given its
importance. It describes in very eloquent terms, the Tandem
philosophy.
6:07 p.m.
On 30 Oct 2007 at 20:16, Dave McGuire wrote:
Actually at least one of their systems (I don't
remember what it was
called) does use a voting scheme, according to my old friend (and
former employer, and DEC20 hacker) Doug Humphrey, who worked for Tandem
for many years.
Quite possible, and probably later than my own exposure to their
systems (mid 80's) and perhaps not transaction-oriented. There were
other contenders in the field, most notably Stratus.
I remember that one of the early online computer-gear auction sites,
OnSale used Tandem gear.
Cheers,
Chuck
31 Oct
31 Oct
8:32 a.m.
On Oct 30, 2007, at 9:07 PM, Chuck Guzis wrote:
Definitely later...the machines that were described to me were
ones that I saw running in production at a Tandem facility in
Maryland in early 1993.
-Dave
--
Dave McGuire
Port Charlotte, FL
Farewell Ophelia, 9/22/1991 - 7/25/2007
Actually at
least one of their systems (I don't remember what
it was
called) does use a voting scheme, according to my old friend (and
former employer, and DEC20 hacker) Doug Humphrey, who worked for
Tandem
for many years.
Quite possible, and probably later than my own exposure to their
systems (mid 80's) and perhaps not transaction-oriented.
30 Oct
30 Oct
5:10 p.m.
On Oct 30, 2007, at 10:19 AM, Sridhar Ayengar wrote:
Refresh my memory how those worked? Two processors in lock-step?
Three processors in a voting quorum?
I don't know which machines are which, but the ones Doug Humphrey
showed me (when he worked at Tandem) used three R3000 processors in a
voting system. It was very impressive.
-Dave
--
Dave McGuire
Port Charlotte, FL
There's also many boards for a (can't remember
the name, it starts
with "T" and is the ultra-high-reliability system that runs 2 or 4
processors in parallel. Think it's PA-RISC, but can't recall for
sure). I don't have them, but can pick them up tomorrow if anyones
interested.
Tandem? If so, those will almost definitely be MIPS processors.
6262
days inactive
6264
days old
11 comments
8 participants
participants (8)
-
cclist＠sydex.com -
cisin＠xenosoft.com -
compoobah＠valleyimplants.com -
doc＠mdrconsult.com -
mcguire＠neurotica.com -
ploopster＠gmail.com -
wdonzelli＠gmail.com -
witchy＠binarydinosaurs.co.uk