Multiple Users and Multiple Inputs on One Machine? 83
BozoForPresident asks: "Not long after seeing a dual monitor setup for the first time I thought how useful it'd be to plug in another keyboard and mouse for a second user. That $4000 dual headed laptop (reported on Slashdot on Sunday March 16) becomes a more viable purchase when you add a couple of USB keyboards and mice for an additional user. Microsoft will never do it but how difficult would it be to make Linux handle 2 (or more) streams of input and direct them to their respective windows?"
Congratulations (Score:5, Funny)
Re:Congratulations (Score:1)
How lame is it that a question like this is being asked about a time sharing system like Linux?
How did something like this get to be an 'ask slashdot' question?
And why would anybody crowd two people onto one machine in this day and age when most of us have whole networks of multiple machines at our disposal, i.e. single user, multiple machines?
Re:Congratulations (Score:1)
Unless you are running Power over Ethernet (not likley on a real computers system), this simply means you have some paperweights with a network connection, and no power source.
(I know what you meant, but as a geek you should apreciate attention to detail.)
Re:Congratulations (Score:1)
apreciate or appreciate?
Ironic isn't it?
What's that about judging others, hmmm...
Re:Congratulations (Score:5, Insightful)
Have a nice day.
Re:Congratulations (Score:1)
Is this gonna turn into a forum for people whining because the connector from their phone doesn't plug into their ethernet jack??
Re:Congratulations (Score:1, Redundant)
Re:Congratulations (Score:2)
Re:Congratulations (Score:2)
Re:Congratulations (Score:1)
Almost modded it as "overrated", as I see your point, but hey - I want to reply this.
Do you see Linux as your community, guarded by thick-bearded philosophers? Is linux an OpenSource-minded-only-OS? Is no "microsoftian citizen" allowed in your [linuxian] world?
Otherwise I agree with you. Having funny comments instead of constructive ones brings no more value to people asking slashdot.
Are these t
Re:Congratulations (Score:2)
Are the answers cluefull?
why would anybody crowd two people onto one machine in this day and age when most of us have whole networks of multiple machines at our disposal, i.e. single user, multiple machines?
Single user, no interaction with other users. Might as well use Big Chief tablets or clay tablets.
In this day, what we want is multiple user, multiple machine, which is a hard (ie many-to-many) problem, hence an interesting problem.
The Recipe (Score:3, Funny)
For second serving:
Add video card. Sift in mouse port and keyboard device (USB recommended when serving more than one). Let blend in x11 conf file. Bind X11. Serve.
Don't forget audio. Can be nice to have multiple
audio out as well.
Hilarity ensues as multiple X desktops compete for such things as CD Drives.
It shouldn't be hard at all. (Score:5, Informative)
Incidentally, you may want to check out this review [dansdata.com] of a product that does something similar in Windows, again using multiple video cards.
Alternately, you may want to cruise Ebay for some secondhand X terminals. While they tend to be ridiculously expensive new (on the order of a whole new PC), you may be able to find someone with a few they just want to get rid of. Of course, check out the specs before hand and cruise Google to make sure that they'll work under Linux without any special hardware or software. X may be an open protocol, but it never hurts to be sure.
With USB devices and a recent XFree86, no (Score:5, Informative)
As an alt to an X terminal, try a diskless fanless thin-client box. Motium [motium.com.au] make those with some really special features, but I don't know if the whizz-bang ones are ready for sale yet.
Re:With USB devices and a recent XFree86, no (Score:3, Interesting)
Also, it seems to me that you wouldn't really need more than one textmode console, since you can run xterm/rxvt/konsole/gnome-terminal on an X-only KVM head. The only times you really need a real console are during bootup and emergencies, when two people using the system
Re:With USB devices and a recent XFree86, no (Score:2, Insightful)
PS/2 is PS/2 is PS/2; you can plug two PS/2 mice or two PS/2 keyboards into a standard machine, diddle with the drivers to tell them about the alternate IO and IRQ addresses and you're away. You cal also get multi-PS/2 port adapters and a lot of the "high-speed serial port" adapters are close enough to 5V RS232 (which is what a PS/2 port is) to work.
That's
Re:With USB devices and a recent XFree86, no (Score:1, Interesting)
PS/2 is most definately NOT 5V RS232. For one things, RS232 doesn't has two data lines, not a single bidirectional one, and no external clock. The bit period is between 60 and 100 microseconds, which means less than 19200 bits per second. I wouldn't call serial "high-speed" until you got well above 10 times that.
PS/2 vs RS232 (Score:2)
No [indiacam.net].
Are you just making your name up as you go along? (-:
Re:With USB devices and a recent XFree86, no (Score:2)
<pointy haired boss>
Actually, that would be a real asset. My database server crashed down last week, and it took my admin 8 hours to bring it back up. If we could have two admins working on it simultaneously, that'd only be 4 hours.
Please excuse me now as I have to start dinner. This chicken was supposed to roast for 6 hours, but I'll just turn t
Re:With USB devices and a recent XFree86, no (Score:2)
486es do work as an X terminal (Score:2)
Re:486es do work as an X terminal (Score:2)
Re:486es do work as an X terminal (Score:1)
Uhm, on anything faster than a 486, MP3 decoding is not terribly taxing on the CPU. It used to take 100% of my 486DX2/66. (Technically, I was decoding MP2s at the time, but the processing requirements for decode are similar.) Now MP3 decoding takes about 5% of the CPU on my 6-year old Pentium II-300. I can't imagine it taking up more than 1% of a modern machine.
Perhaps you meant ripping and encoding? Both of those are much more CPU intensive. Or perhaps you mean "Running eye candy visualizations"?
Re:486es do work as an X terminal (Score:2)
Therefore unusable on even a 486DX4-120, the fastest 486 I know of. If it's sucking 100% CPU locally - make that 50% for a hypothetically faster CPU but IRL probably around 70% - add in the overhead of fetching from the net, try to display something at the same time, and you're a dead duck.
Re:486es do work as an X terminal (Score:2)
For a while, I let others log into one of the linux boxes this way, 'cause their boxes were too underpowered to handle both graphics and any real apps.
Re:486es do work as an X terminal (Score:2)
I was speaking of borrowing back horsepower from the client to reduce network load. Playing MP3 or Ogg files locally costs roughly 10x less LAN traffic and is much less laggy. This applies much more so for video or 3D stuff. A 486 is generally not up to decoding MP3s, look toward a Pentium over 100MHz as a working minimum local-Ogg player.
Re:486es do work as an X terminal (Score:1)
the 486 will only have to run X, and will be connected to a machine, with a fairly fast connection... like 100mbit ethernet
Re:It shouldn't be hard at all. (Score:2, Informative)
Re:It shouldn't be hard at all. (Score:5, Informative)
Re:It shouldn't be hard at all. (Score:1)
This is partially true, however there are a small number of GeForce4 MX cards available in a PCI version (I use one myself; my desktop system is a strange Athlon server with no available AGP slot). You will not be able to make use of streaming AGP textures, of course, but it's more than sufficient for low- to mid-range OpenGL apps.
What about sound? (Score:2)
I've considered this. However I can't figgure out how to make sound work. X11 assumes you have a DISPLAY variable set, and sends data to that, so you can have as many different screens as you wish. (Up to some limit). There is no standard way to do sound in that manor. Many different things are trying, but none are universial, so even if you get something to work, it won't work with much.
I understand that X11 now has a sound extnetion, which could solve this problem and is standard enough that it is
Difficult? You jest, sir! (Score:3, Informative)
BTW did you know that you can also run multiple virtual X sessions (similar to the virtual terminals but graphical) on the same display/keyboard/mouse? I have 2 sessions running on my machine at home.
There is software for windows to do up to 5 (Score:5, Informative)
Hook up to four additional USB keyboards and mice, and a monitor for each station (obviously you'd need more video cards if you want more than two stations) and it treats them all as seperate computers.
I found out about it because MSI bundles a two station version with the geforce 4x00 cards. I haven't tried it, though.
It works for windows.
-Adam
Re:There is software for windows to do up to 5 (Score:2)
Some SGIs do this (Score:2)
This can also be done on the Octane, but requires a PS/2 keys/mouse interface PCI card.
I would suggest looking at the XFree
Can be done in X server level easily (Score:1)
You just play with the input and output methods and create two screens.
and then ? (Score:1)
Re:and then ? (Score:2, Funny)
Re:and then ? (Score:5, Interesting)
Software Licensing - or at least that's why I was asked to look into some bizarre korean multihead cards back in 1999.
At the place I was working at that time, they used some expensive software that was licensed per processor. If one user used the software on a dual cpu machine, 2 licenses would be checked out. If he was on a single CPU machine one license would be checked out. Multiple instances of the software running on the same machine did not check out any additional licenses.
The idea was, to stick some of these strange cards into a bunch of machines, and put the users who were in training on these boxes. The resule: 2 users per license, saving up some licenses for the people who needed to run the program on the multicpu boxes.
The cards were completey unsuitable, and burned out quickly, so the project never went anywhere.
Re:and then ? (Score:1)
Also, this just has the interesting factor. Sure you could just plug in another computer but why not try to optimize the hardware that already exists. Many people own a ghz level processor and still only need to surf the web and read email. A setup like this would work fin
Re:and then ? (Score:1)
Troll? (Score:2, Troll)
Whats up with the ask slashdot trolls as of late... come on!
Last time i checked Windows already supported -
Fast User Switching
Multiple Mice
Multiple Keyboard
Multiple Monitors
Try windows XP for the fast user switching,
Multiple monitors have been there since win98.
And just try plugging a USB keyboard/mouse into your laptop and you'll see that the orginals and usb ones work at the same time!
So it isn't like they're that far from alre
Re:Troll? (Score:1)
...and no one likes people who don't read the question.
How exactly are you proposing to bind one keyboard/mouse pair to one monitor using XP? Are you suggesting that different users could be logged in to different displays at the same time?
Re:Troll? (Score:1, Redundant)
He wasn't saying it was possible, but that it was hardly a long way off for Windows NT.
Re:Troll? (Score:2)
With open source, you have the power to do whatever you need to do. See this project [puc-rio.br] on multi-user X for an example. It's not pretty, but someone got it to work.
The original poster was quite correct. MS will Never supp
Re:Troll? (Score:2)
Remember - you are dealing with a closed source system. Kinda like being in a jail cell with the keys hanging on the wall outside that you can barely feel with your finger tips.
Windows YP, codename: Tantalus [mac.com]
I saw this on windows back in 1999 (Score:2)
A manager had been somewhere in southeast asia, and had picked up a few sets of a very strange device. They were pci cards that packed a low end video card, and some logic into a single package. Each one had a RJ-45 jack on the back, that connected to a little pod which hooked to a keyboard, monitor, etc to allow a second (third, etc...) user to have their own workspace and desktop on the host machine.
They only w
Re:I saw this on windows back in 1999 (Score:3, Informative)
Might as well have a PC for each person (Score:1)
XP: $300
Office XP std: $480
Monitor, KB, mouse: $200
Cost of HW for extra kb, mouse and monitor?
Plus the convienance of something freezing for one person and then having more than one person wait on a reboot.
That is $980. A new PC is $1000. Where are your savings? The $1000 is a new dell with a refurb monitor with XP pro and Office Standard. Plus 256MB of mem.
Re:Might as well have a PC for each person (Score:4, Funny)
Keyboard $10
Mouse $5
Cheap dual-head AGP video $65
Linux: Free
The look on Bill's face: Priceless.
Re:Might as well have a PC for each person (Score:2, Interesting)
Prior Ask /. on the same topic (Score:5, Informative)
There was a tutorial [linuxplanet.com] mentioned in the comments.
Re:Prior Ask /. on the same topic (Score:1)
Should not be difficult to do (Score:1)
Was on LKML recently (Score:4, Insightful)
This question was asked on the Linux kernel mailing list a while ago. The response was (from memory):
Yes, you can have 2 keyboards, mice and video cards in a single PC. And you can run 2 instances of X on different virtual consoles. But, there can be only one active VC at any time, and it's hard to change that limit.
The conclusion was that it would probably be easier and cheaper to set up an X terminal.
you can do it on windows already (Score:3, Informative)
check here [igcinc.com], here [thinsoftinc.com], or here [cyclopstech.com.hk].
And this is better than buying two computers how? (Score:2)
The idea seemed cool to me, at first. But the inconveniences didn't seem to balance the cost-savings.
And with powerful new computers so cheap now, I think it makes even less sense today. How much did an ethernet card cost back then?
Re:And this is better than buying two computers ho (Score:1)
Now if both users were continually running CPU intensive tasks, then there wouldnt be that much of an advantage. But in many cases such as web surfing, word proccessing, programming, etc, there is a lot of CPU cycles which are simply wasted - CPU usage is NOT constantly at 100%. In a
Trying to justify the question (Score:1)
Already done (Score:3, Interesting)
Use dumb graphical terminals? (Score:2)
This centralized computing model saved some HP-UX licenses. It later became obsolete when we started adapting linux.
anothe roption I would probably look into is Xvnc. (Real VNC [realvnc.com]) Unlike it's Windows counter part, it allows you to set up multiple independent desktops.
Re:Use dumb graphical terminals? (Score:2)
I actually got to use them at the benchmarking center and you could not tell they were not running x native (IMHO). Well this is not a Linux solution it is an X / Unix solution and the Sun Ray may even work with a Linux X server. Something to look at at least.
Wow, talk about niche markets! (Score:1, Funny)
What about VPC? (Score:2)
Haven't tried it, but sounds like its worth a try for the windows side...
get "thin" clients (Score:2)
You can then either boot the machine from an Linux Terminal Server [ltsp.org] floppy or CD, or from something like a Knoppix CD [knoppix.de], or you can netboot them; you don't even have to bother installing anything loca
Can't be arsed (Score:2)
1 server and N diskless PXE enabled machines. You can do it for about $150 per machine.
Check out Synergy (Score:1)