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Groups > alt.folklore.computers > #211694
| From | usenet@only.tnx (Questor) |
|---|---|
| Newsgroups | alt.folklore.computers |
| Subject | Re: mainframe I/O, was CR or LF? |
| Organization | random access |
| Message-ID | <5ed69e60.6633748@news.dslextreme.com> (permalink) |
| References | (2 earlier) <365b2c24-3b9f-4eba-9c67-d31688bdfe5c@googlegroups.com> <ragp4c222lo@news3.newsguy.com> <ragrus$30jf$2@gal.iecc.com> <rautav$b9f$1@z-news.wcss.wroc.pl> <ravpve$ja5$1@dont-email.me> |
| Date | 2020-06-02 19:12 +0000 |
On Sun, 31 May 2020 09:30:37 +0100, David Wade <g4ugm@dave.invalid> wrote: >On 31/05/2020 01:21, antispam@math.uni.wroc.pl wrote: >>John Levine <johnl@taugh.com> wrote: >>> >>>I suppose that hypothetically someone could have built a TTY channel >>>interface that interrupted on every character but I would be surprised >>>if anyone did. More likely they'd sell you an 1130 or later a Sys/7 to >>>be an overpriced front end processor. > >You can't use an IBM1130 as a terminal concentrator. It doesn't have >terminal lines. IBM of course wanted you to use 3270 VDU's where >character editing was done in a local terminal controller. >If you can offload some processing to a less expensive front end box >rather than buy Mainframe MIPS thats a win... > >>Around 1992 I was using Internet connection (email) that did it. >>Connection was from a PC via modem to IBM mainframe. AFAIU doing >>it "proper" way would be complicated/expensive, do guys operating >>mainframe hacked hardware to take interrupt on each incoming >>character. They said that "IBM does not like interrupts", but >>this was for single 9600 bps line, so mainframe could handle >>interrupts without serious degradation of response. > >Are you sure it really passed each character over the channel, could you >run EMACS? Its not really the interupts that slow down mainframes its >the VTAM layers in between. > >No computer likes interrupts. I remember a friend who worked for a big >UK bank was keen to roll out "all-in-one" to all bank staff, but he said >it needed so many VAXs compared PROFS on the IBM he couldn't cost >justify it. > >I believe senior managers up got all-in-one the rest got PROFS. Depending on when this decision was made, and consequently what VAX models were available, it may have hinged more on the relative processing power of the two machines rather than interrupts and differences in character processing. The initial VAX 780 was an approximately one MIPS machine and could handle perhaps thirty or forty general timesharing users. I don't know what kind of load All-In-One presented, but I would expect it might be similar, assuming active users. >>Doing this on multiple lines probably would overload mainframe >>with interrput processing. This mainframe probably had about 20 >>discs and 100 block mode terminals and my guesstimate is that >>the single character mode line generated comparable number >>of interrupts to all other periferials taken together... I will interject here that DEC's PDP-10 mainframes had a front-end processor -- in most cases a PDP-11 minicomputer -- that handled all the terminal lines, so character interrupts and echoing were not an issue. And most programs used "line mode" input -- they go into an I/O wait state while the user types and characters get stashed in a buffer. When the user types one of the end-of-line characters (CR, LF, VT, FF, or ESC) then the program wakes up and can retrieve them. It's been too many years, and it's a bit outside my bailiwick, so I can't recall what happens if the user simply types and types without an end-of-line. When the buffer is full either the characters are thrown away, or an end-of-line is forced; I don't remember which. >Well the VAX suffers the same. Lets see:- > >1. User Types Character >2. VAX receives character. >3. VMS looks and sees its for a running application which is swapped. >4. It pages in the interupt handler. >5. It passes the character to application >6. The program looks at the character. Sees its a letter "F" >7. The program decides it needs to echo the character so asks the OS to >send a "P" to the terminal >8. The program goes to sleep >9. VMS pages it out to make room for another program that needs to >process a leetter "U" ..... > >So on a heavily loaded system thats two disk IO's for each character >typed. I am sure there must be a better way.... I will confess ignorance on how VAX/VMS processed characters, but I can't imagine it was this bad. I strongly suspect it had a "line mode" input model similar to the PDP-10 that was used by most programs. I very much doubt that the processor was interrupted on every character typed by every user. I could be wrong though; VMS certainly made some other big mistakes. There was a strong "NIH" current in Spit Brook and they often ignored the lessons learned by the software engineers working on other DEC operating systems.
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CR or LF? Gareth Evans <headstone255@yahoo.com> - 2020-04-12 11:59 +0100
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-04-12 20:35 +0000
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-04-12 16:52 -0400
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-04-13 22:16 +0000
Re: CR or LF? Gareth Evans <headstone255@yahoo.com> - 2020-04-12 22:48 +0100
Re: CR or LF? Mike Spencer <mds@bogus.nodomain.nowhere> - 2020-04-12 19:44 -0300
Re: CR or LF? Douglas Miller <durgadas311@gmail.com> - 2020-04-12 16:38 -0700
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-04-13 19:03 +0000
Re: CR or LF? Douglas Miller <durgadas311@gmail.com> - 2020-04-13 14:12 -0700
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-04-13 22:30 +0000
Re: CR or LF? Douglas Miller <durgadas311@gmail.com> - 2020-04-13 16:00 -0700
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-04-13 21:22 +0000
Re: CR or LF? Thomas Koenig <tkoenig@netcologne.de> - 2020-04-14 09:40 +0000
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-13 17:56 -0700
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-04-13 03:32 +0000
Re: CR or LF? "Carlos E.R." <robin_listas@es.invalid> - 2020-04-14 05:26 +0200
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-12 22:11 -0700
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-04-13 17:15 +0000
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-13 16:40 -0700
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-13 17:29 -0700
Re: CR or LF? Douglas Miller <durgadas311@gmail.com> - 2020-04-13 18:18 -0700
Re: CR or LF? Niklas Karlsson <anksil@yahoo.se> - 2020-04-16 13:40 +0000
Re: CR or LF? maus <maus@dmaus.org> - 2020-04-17 11:00 +0000
Re: CR or LF? Niklas Karlsson <anksil@yahoo.se> - 2020-04-18 09:56 +0000
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-04-13 21:37 -0400
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-14 14:51 -0700
Re: CR or LF? Bob Eager <news0073@eager.cx> - 2020-04-14 07:45 +0000
Re: CR or LF? Gareth Evans <headstone255@yahoo.com> - 2020-04-14 11:38 +0100
Re: CR or LF? "Carlos E.R." <robin_listas@es.invalid> - 2020-04-14 15:28 +0200
Re: CR or LF? nobody@example.org (Scott) - 2020-04-14 15:27 +0000
Re: CR or LF? Gareth Evans <headstone255@yahoo.com> - 2020-04-14 17:37 +0100
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-14 15:00 -0700
Re: CR or LF? fred_weigel@hotmail.com - 2020-05-22 17:09 -0700
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-23 03:37 -0700
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-23 08:36 -0400
Re: CR or LF? robin.vowels@gmail.com - 2020-05-23 05:38 -0700
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-05-23 08:58 -0400
Re: base64, not really CR or LF? John Levine <johnl@taugh.com> - 2020-05-23 18:42 +0000
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-05-23 19:28 +0000
Re: CR or LF? Bob Eager <news0073@eager.cx> - 2020-05-23 20:27 +0000
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-23 14:30 -0700
Re: CR or LF? "Kerr-Mudd,John" <notsaying@invalid.org> - 2020-05-24 10:21 +0000
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-05-24 06:06 +0000
Re: CR or LF? Bob Eager <news0073@eager.cx> - 2020-05-24 10:45 +0000
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-24 07:03 -0700
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-24 10:43 -0400
Re: CR or LF? Jan van den Broek <fortytwo@xs4all.nl> - 2020-06-05 22:22 +0100
Re: CR or LF? Mike Spencer <mds@bogus.nodomain.nowhere> - 2020-04-14 17:49 -0300
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-14 06:29 -0700
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-18 08:42 +0100
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-18 11:33 -0700
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-04-18 19:11 +0000
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-04-18 18:32 -0400
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-04-19 01:55 +0000
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-04-18 20:03 +0000
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-18 22:44 +0100
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-04-19 08:46 +0000
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-19 10:58 +0100
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-04-18 22:22 +0000
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-04-18 18:55 -0400
re: CRLF Peter Flass <peter_flass@yahoo.com> - 2020-04-18 18:03 -0700
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-04-19 08:55 +0000
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-04-19 08:16 -0400
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-04-19 09:19 -0400
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-04-19 10:24 -0400
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-19 10:47 -0700
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-04-20 16:02 +0000
Re: CR or LF? Jan van den Broek <fortytwo@xs4all.nl> - 2020-05-05 16:32 +0100
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-04-19 14:54 +0000
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-04-19 12:19 -0400
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-19 10:47 -0700
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-19 09:26 -0700
Re: CR or LF? Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2020-04-20 17:40 +0800
Re: CR or LF? Fred Smith <fred@thejanitor.corp> - 2020-04-20 23:05 +0000
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-04-21 06:07 +0000
Re: CR or LF? Rich Alderson <news@alderson.users.panix.com> - 2020-04-22 15:08 -0400
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-04-22 20:22 +0000
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-04-22 19:40 -0400
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-04-22 23:23 -0700
Re: CR or LF? robin.vowels@gmail.com - 2020-04-23 03:01 -0700
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-04-19 10:47 -0700
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-13 19:54 +0100
Re: CR or LF? hancock4@bbs.cpcn.com - 2020-08-22 11:18 -0700
Re: CR or LF? "Carlos E.R." <robin_listas@es.invalid> - 2020-04-14 05:24 +0200
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-18 08:44 +0100
Re: CR or LF? "Carlos E.R." <robin_listas@es.invalid> - 2020-04-18 12:08 +0200
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-04-18 12:02 +0100
Re: CR or LF? "Carlos E.R." <robin_listas@es.invalid> - 2020-04-18 21:50 +0200
Re: CR or LF? usenet@only.tnx (Questor) - 2020-04-18 03:40 +0000
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-23 03:40 -0700
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-23 08:38 -0400
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-23 08:02 -0700
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-23 11:07 -0400
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-23 11:27 -0700
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-23 12:27 -0700
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-23 18:21 -0400
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-23 20:10 +0000
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-24 08:32 -0700
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-05-24 16:25 +0000
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-24 18:29 +0000
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-05-25 02:00 +0000
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-25 16:28 +0000
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-05-26 14:06 +0000
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-05-26 15:14 +0000
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-25 10:55 -0700
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-05-25 15:04 -0400
Re: CR or LF? robin.vowels@gmail.com - 2020-05-24 21:32 -0700
Re: CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-05-25 15:44 +0000
Re: mainframe I/O, was CR or LF? John Levine <johnl@taugh.com> - 2020-05-25 16:32 +0000
Re: mainframe I/O, was CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-05-26 00:39 +0000
Re: mainframe I/O, was CR or LF? antispam@math.uni.wroc.pl - 2020-05-31 00:21 +0000
Re: mainframe I/O, was CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-30 21:59 -0400
Re: mainframe I/O, was CR or LF? David Wade <g4ugm@dave.invalid> - 2020-05-31 09:30 +0100
Re: mainframe I/O, was CR or LF? antispam@math.uni.wroc.pl - 2020-05-31 15:48 +0000
Re: mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-31 13:49 -0700
Re: mainframe I/O, was CR or LF? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2020-06-01 16:28 +0000
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-01 18:48 +0000
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-01 16:27 +0000
Re: mainframe I/O, was CR or LF? usenet@only.tnx (Questor) - 2020-06-02 19:12 +0000
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-02 20:28 +0000
Re: mainframe I/O, was CR or LF? David Wade <g4ugm@dave.invalid> - 2020-06-03 09:13 +0100
Re: mainframe I/O, was CR or LF? Fred Smith <fred@thejanitor.corp> - 2020-06-03 08:33 +0000
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-03 16:20 +0000
Re: mainframe I/O, was CR or LF? usenet@only.tnx (Questor) - 2020-06-03 18:25 +0000
Re: mainframe I/O, was CR or LF? Rich Alderson <news@alderson.users.panix.com> - 2020-06-03 17:20 -0400
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-04 15:20 +0000
Re: mainframe I/O, was CR or LF? John Levine <johnl@taugh.com> - 2020-06-04 19:51 +0000
Re: mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-06-04 16:26 -0700
Re: mainframe I/O, was CR or LF? usenet@only.tnx (Questor) - 2020-06-05 18:46 +0000
Re: mainframe I/O, was CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-06-05 12:26 -0700
Re: mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-06-05 13:28 -0700
Re: mainframe I/O, was CR or LF? David Lesher <wb8foz@panix.com> - 2020-06-08 01:03 +0000
Re: PDP-11s, was mainframe I/O, was CR or LF? John Levine <johnl@taugh.com> - 2020-06-06 00:08 +0000
Re: mainframe I/O, was CR or LF? usenet@only.tnx (Questor) - 2020-06-04 17:41 +0000
Re: mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-06-04 16:26 -0700
Re: mainframe I/O, was CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-06-04 17:04 -0700
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-04 15:18 +0000
Re: memory sizes, mainframe I/O, was CR or LF? John Levine <johnl@taugh.com> - 2020-06-04 20:53 +0000
Re: memory sizes, mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-04 22:22 +0000
Re: memory sizes, mainframe I/O, was CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-06-04 19:27 -0400
Re: memory sizes, mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-05 16:10 +0000
Re: memory sizes, mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-06-05 10:03 -0700
Re: memory sizes, mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-05 20:29 +0000
Re: memory sizes, mainframe I/O, was CR or LF? usenet@only.tnx (Questor) - 2020-06-05 18:47 +0000
Re: mainframe I/O, was CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-06-04 16:26 -0700
Re: mainframe I/O, was CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-06-01 16:32 +0000
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-25 10:55 -0700
Re: CR or LF? Anne & Lynn Wheeler <lynn@garlic.com> - 2020-05-25 15:04 -1000
Re: CR or LF? Peter Flass <peter_flass@yahoo.com> - 2020-05-26 12:56 -0700
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-26 14:15 -0700
Re: CR or LF? robin.vowels@gmail.com - 2020-05-25 21:41 -0700
Re: CR or LF? Thomas Koenig <tkoenig@netcologne.de> - 2020-05-28 11:50 +0000
Re: CR or LF? Bob Eager <news0073@eager.cx> - 2020-05-28 11:56 +0000
Re: CR or LF? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-05-30 14:49 +0000
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-30 17:39 +0000
Re: CR or LF? scott@slp53.sl.home (Scott Lurndal) - 2020-05-30 19:07 +0000
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-30 19:32 +0000
Re: CR or LF? Quadibloc <jsavard@ecn.ab.ca> - 2020-05-30 13:10 -0700
Re: CR or LF? John Levine <johnl@taugh.com> - 2020-05-30 20:43 +0000
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-05-30 15:50 -0400
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-30 16:30 -0400
Re: CR or LF? Dan Espen <dan1espen@gmail.com> - 2020-05-30 19:42 -0400
Re: CR or LF? J. Clarke <jclarke.873638@gmail.com> - 2020-05-30 22:17 -0400
Re: CR or LF? Ahem A Rivet's Shot <steveo@eircom.net> - 2020-05-31 09:45 +0100
Re: CR or LF? usenet@only.tnx (Questor) - 2020-05-25 18:37 +0000
Re: CR or LF? Bob Eager <news0073@eager.cx> - 2020-05-25 19:52 +0000
Re: CR or LF? usenet@only.tnx (Questor) - 2020-05-25 07:37 +0000
Re: CR or LF? hancock4@bbs.cpcn.com - 2020-08-22 11:15 -0700
Re: CR or LF? Robin Vowels <robin.vowels@gmail.com> - 2020-08-22 18:55 -0700
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