duncan@csd4.milw.wisc.edu (Shan D Duncan) (02/27/89)
This in the feb. 20th issue of computerworld Wall St. money rides on PC's and It's real time on Wall Street Both articles stress the importance of multitasking to the average wall street broker. They state they use multiple-terminal trading workstations with dedicated graphic feed cables. When moving the terminals it can cost close to $2,000 to 20,000 depending how many cables have to be ripped up and moved. So what are the features wall street looks for in a "financial workstation"? 1. Powerful networked microcomputers 2. Presentation and user interface standards 3. MULTITASKING 4. Real-time applications 5. Dynamic data exchange support 6. Financial modeling environment 7. Real-time and historical data access to corporate databases Options listed: Wall of dedicated terminals Unix workstation (suns dominate at the moment) Pc's with Microsoft Windows Macintosh IIs The consensus of this article is that unix workstations can not deliver all they promise and PC's using windows might be the way to go. Now the questions. Is there anything a PC with windows can do in this area that the amiga can not (probably cheaper and better) EXCEPT for the non Fortune 1000 image? Please note that in this area Multitasking is a MUST not an option. Anytime real-time applications are needed multitasking is needed. So soon will we see mutitasking examples using two or more serial ports. THAT just might anyone.
schow@bnr-public.uucp (Stanley Chow) (02/28/89)
In article <1295@csd4.milw.wisc.edu> duncan@csd4.milw.wisc.edu (Shan D Duncan) writes: [Shan reports on the Wall Street requirements for computers. SC] > >Now the questions. Is there anything a PC with windows can do in this >area that the amiga can not (probably cheaper and better) EXCEPT for >the non Fortune 1000 image? > The Amiga can do many more things than a PC with windows. The PC can also do lots more things than the Amiga. The software available for the two systems are very different. I doubt you will find many brokers needing 3-D modelling or ray-tracing just as I doubt you will find the accounting programs on the Amiga. Stanley Chow ..!utgpu!bnr-vpa!bnr-fos!schow%bnr-public (613) 763-2831 No person or organization has paid me for this opinion, so I will sue anyone who claims to be represented by said opinion.
steve@morgoth.UUCP (Steve Hall) (03/01/89)
In article 26822, duncan@csd4.milw.wisc.edu (Shan D Duncan) writes: > Wall St. money rides on PC's > and > It's real time on Wall Street > [stuff deleted] > > Now the questions. Is there anything a PC with windows can do in this > area that the amiga can not (probably cheaper and better) EXCEPT for > the non Fortune 1000 image? Please correct me if I'm wrong (and I very well could be :-), but I thought that there was an inherent problem using non-parity protected RAM for doing lots of meticulous financial record keeping. Something about the contents changing... Mind you, I heard this through someone else and I could be way off base. On a related note, if this _is_ a problem, which RAM expansion cards come with parity chips? I know the Starboard II has optional parity chips, but do any other manufacturers also have this? -= Steve =- -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- LIVE: Steve Hall (617)969-0050 | Disclaimer: If ARPA: adelie!morgoth!steve@harvard.HARVARD.EDU | confronted, I'll deny UUCP: {harvard|ll-xn|mirror|axiom}!adelie!morgoth!steve | I ever said anything.
rar@auc.UUCP (Rodney Ricks) (03/03/89)
In article <503@morgoth.UUCP> steve@morgoth.UUCP (Steve Hall) writes: >In article 26822, duncan@csd4.milw.wisc.edu (Shan D Duncan) writes: >> Wall St. money rides on PC's >> and >> It's real time on Wall Street >> >[stuff deleted] >> >> Now the questions. Is there anything a PC with windows can do in this >> area that the amiga can not (probably cheaper and better) EXCEPT for >> the non Fortune 1000 image? > >Please correct me if I'm wrong (and I very well could be :-), but I >thought that there was an inherent problem using non-parity protected >RAM for doing lots of meticulous financial record keeping. Something >about the contents changing... > >Mind you, I heard this through someone else and I could be way off >base. Actually, I think that you may be. Parity checking on the IBM PC has a MAJOR problem. Say the system finds a parity error. What does it do; how does it recover? Recover, what does recover mean? If a parity error is found, the system puts up an error message: PARITY ERROR in large, 40-column text, up at the top left of the screen, AND LOCKS up. Great for real-time systems on Wall Street, huh? Also, from what I've heard, Parity Errors on personal computer RAM chips are EXTREMELY rare. IBM's "solution" seems to just make the problem worse. I'm no expert on the matter, so I may, of course, be wrong (and I KNOW someone will tell me if I am...). Maybe there's some system call to catch it and stop if from crashing ... nahhh! If that were the case, why didn't they give you some way of recovering, in their own, elegant, MSDOS style? :-) Memory Parity Error. Abort, Retry, or Ignore? There are some companies that offer error-checking and correction boards. Of course, the problem here is that the main system memory will still be just parity checked, without correction or recovery. Of course, what's to stop people from making memory error checking / recovery boards for the Amiga? In fact, I remember seeing some advertised awhile back. > On a related note, if this _is_ a problem, which RAM expansion >cards come with parity chips? I know the Starboard II has optional >parity chips, but do any other manufacturers also have this? Actually, I've heard the following opinion from someone: Since the PC has so many extra RAM chips for parity checking (12.5% extra), the extra RAM chips INCREASE the possibility of parity errors, and, since not all parity errors will be detected (what if 2 bits per [9-bit] byte change? or any even number of bits?), the extra chips for parity detection aren't worth it, and may even make the system less reliable. > -= Steve =- "We may have come over here in different ships, but we're all in the same boat now." -- Jesse Jackson Rodney Ricks, Atlanta University Center Computation Center -- "We may have come over here in different ships, but we're all in the same boat now." -- Jesse Jackson Rodney Ricks, Atlanta University Center Computation Center
martens@furlong.cis.ohio-state.edu (Jeff Martens) (03/04/89)
In article <32244@auc.UUCP> rar@auc.UUCP (Rodney Ricks) writes:
[deleted stuff from various places below...]
:Actually, I think that you may be. Parity checking on the IBM PC has a
:MAJOR problem. Say the system finds a parity error. What does it do; how
:does it recover?
:
:Recover, what does recover mean? If a parity error is found, the system
:puts up an error message:
:
:PARITY ERROR
:
:in large, 40-column text, up at the top left of the screen, AND LOCKS up.
:Great for real-time systems on Wall Street, huh?
:
:Also, from what I've heard, Parity Errors on personal computer RAM chips
:are EXTREMELY rare. IBM's "solution" seems to just make the problem worse.
:
:There are some companies that offer error-checking and correction boards.
:Of course, the problem here is that the main system memory will still be
:just parity checked, without correction or recovery.
:
:Of course, what's to stop people from making memory error checking /
:recovery boards for the Amiga? In fact, I remember seeing some advertised
:awhile back.
:Actually, I've heard the following opinion from someone: Since the PC
:has so many extra RAM chips for parity checking (12.5% extra), the extra
:RAM chips INCREASE the possibility of parity errors, and, since not all
:parity errors will be detected (what if 2 bits per [9-bit] byte change?
:or any even number of bits?), the extra chips for parity detection aren't
:worth it, and may even make the system less reliable.
You make a number of good points. And yes, adding one parity bit does
increase the chances of a parity error by 12.5%, and, if you get a
parity error on an IBM PC there's a 1 in 9 chance it's the parity bit
that's wrong. Basically, although I'm sure there are sales types out
there who will tell you that you need parity checking, it's not worth
doing if you're not gonna do it right, and you can't do it right with
just one parity bit. With more than one bit, you can get into
correction and stuff, but the cost gets prohibitive for most
applications.
-=-
-- Jeff (martens@cis.ohio-state.edu)schow@bnr-public.uucp (Stanley Chow) (03/08/89)
In article <32244@auc.UUCP> rar@auc.UUCP (Rodney Ricks) writes: >Actually, I think that you may be. Parity checking on the IBM PC has a >MAJOR problem. Say the system finds a parity error. What does it do; how >does it recover? > >Recover, what does recover mean? If a parity error is found, the system >puts up an error message: > >PARITY ERROR > >in large, 40-column text, up at the top left of the screen, AND LOCKS up. >Great for real-time systems on Wall Street, huh? > >Also, from what I've heard, Parity Errors on personal computer RAM chips >are EXTREMELY rare. IBM's "solution" seems to just make the problem worse. > >Rodney Ricks, Atlanta University Center Computation Center The question is very simple, which do you prefer: 1) not be told about an error and get an answer. 2) be told about the error but get no answer. Like almost everything in life, different people have different values on parity. When I am play a games, I don't care about the graphics having a bit wrong. I much prefer continuing with the game. There are many other applications for which machines must be very reliable. Image preparing a bit on a multi-million dollar contract, if the wrong bit is flipped, you end up bidding 3 million instead of 7 million. [I can hear it now: but that means you will almost certainly get the contract, isn't that good?] If the computer isn't doing what I told it, I want to know. Coming up with PARITY ERROR with no recovery is better than a wrong answer. Stanley Chow ..!utgpu!bnr-vpa!bnr-fos!schow%bnr-public (613) 763-2831 What? Me? Represent anyone? Don't be radiculas, they only pretend to let me represent myself.
wtm@neoucom.UUCP (Bill Mayhew) (03/10/89)
Unfortunately, once you get an interrupt from a parity error on a PC clone, the architecture of the machine itself prevents your program from taking much of an action other than cold rebooting. To this extent parity checking is not extraordinarily helpful. Unfortunately at the time the original IBM PC-1 was introduced, there weren't any good inexpensive EEC controller components available. Now it would be reasonable to make a memory with EEC so that errors could be detected and most corrected. Nobody has bothered on a PC clone yet as far as I know. Parity chips as used on PC clones are a good way for memory companies to increase their sales volume by 12.5%. I don't find the lack of a a parity bit offensive. Any decent package that is transferring critical data darn well better have some sort of embedded hash digit checking at the software level. Where you get into trouble is when a character is sitting in video ram and a bit glitches causing you to see the wrong thing on the screen. When did you ever see parity bits on video boards? In the IBM world, you could get burned (when not in bit-mapped mode). On the Amiga we win becasue the characters are rendered onto the bitmap; a one-bit glitch is not going to make a 8 -> 9 as it could on a character display. ... and you could tell something was up as the character would look funny. --Bill