Fedora moves the X server [LWN.net]

Fedora moves the X server

Posted Oct 29, 2008 14:56 UTC (Wed) by bboissin (subscriber, #29506) [Link] (6 responses)

If the goal is to be flicker-free, couldn't the kernel start (via a command line argument) directly in tty7 ? Or did I miss something ?

Fedora moves the X server

Posted Oct 29, 2008 14:59 UTC (Wed) by paravoid (subscriber, #32869) [Link] (2 responses)

And besides that, I thought that one of the benefits of kernel mode-setting was flicker-free VT switches...

Fedora moves the X server

Posted Oct 29, 2008 15:10 UTC (Wed) by drag (guest, #31333) [Link] (1 responses)

You still end up seeing the 'ugly' command line prompt.

Also it adds some extra lag to the start up proceedure. Slowing down startups and wake-ups from sleep.

And even if you have flicker-free start-ups on the video card side, changing resolutions will cause some LCD displays to blank out for some time.

All in all it's not going to knock off any dramatic amount of time, but it's worth playing around with to make Linux "seem" much more solid, professional product.

--------------------

As far as I know there is no real technical reason why GDM or any other graphical manager should start up from any tty.

In the future when X moves away from handling hardware with it's own 2-D drivers and it becomes just another userspace application. Then there is going to be very little reason why you would not want to run a half a dozen X servers on a single machine and do away completely with the virtual console-style login for Desktop systems, except maybe one at tty9 or whatever for traditions and sentimental reasons.

Fedora moves the X server

Posted Oct 29, 2008 16:01 UTC (Wed) by acoffman (guest, #4599) [Link]

The point of moving the X server to VT-1 is to improve boot speed - it has
nothing to do with flicker free boot.

Flicker free boot has already been achieved by a different set of changes.

One of which is having the _kernel_ set the video resolution and mode at
boot to match what X will eventually be running so there is no mode switch
during X initialization.

They also do some tricks with the X cursor and a splash screen transition
that is kind of a hack but looks great from the user experience point of
view.

Currently this works on Intel and some Radeon adapters in the Fedora 10
development series. It's very smooth - there is no mode switch or
flickering during boot. There is work ongoing in the Nouveau driver to
bring this to nVidia cards as well.

Fedora moves the X server

Posted Oct 29, 2008 15:26 UTC (Wed) by epa (subscriber, #39769) [Link] (2 responses)

I suppose it could start up in tty7 but what would be the point? Hitting Ctrl-Alt-F1 would then take you to some random virtual console and not the 'first' one used for kernel messages, so some graybeards would still complain.

IMHO, anyone with enough clue to know about virtual consoles and understand the Ctrl-Alt-Fx key combination has enough clue to cycle through F1, F2 etc. until they find the one they want. I always end up having to do that anyway.

I am sure hundreds of HOWTOs and Linux books will become mildly obsolete, but I don't remember such flamewars when replacing init with upstart, or LILO with grub, or fvwm with Enlightenment with Sawfish with Metacity, or any of the other changes Linux distributions have made over the years. It's just that the bikeshed quotient of tty numbers is very high.

Fedora moves the X server

Posted Oct 29, 2008 17:48 UTC (Wed) by PO8 (guest, #41661) [Link]

It should be feasible to modify the Linux kernel so that it logs to VT1, but starts switched to an arbitrary VT specified on the kernel command line. This seems to me like the right fix, achieving the goal of faster boot without otherwise changing the behavior of the system.

Fedora moves the X server

Posted Oct 29, 2008 19:59 UTC (Wed) by jengelh (guest, #33263) [Link]

But having to go through all Ctrl-Alt-Fx to find the X server is just as bad.

Beginning of the End of text-interface era

Posted Oct 29, 2008 15:40 UTC (Wed) by MilanKerslager (guest, #53653) [Link] (5 responses)

We are seeing the beginning (or the middle) of the end of the text-interface era. Next step is text-VTs in graphics mode (aka pseudo-graphics mode I saw in old-time Norton utilities).

Beginning of the End of text-interface era

Posted Oct 29, 2008 15:56 UTC (Wed) by drag (guest, #31333) [Link] (2 responses)

Command-line is infinately usefull and flexible. It's going _nowhere_. It would result in the vast reduction in functionality, increase in complexity, and dramatically reduce the ability for common people to perform simple programming tasks.

As seen with Windows and Apple they have come 'back' from trying to eliminate their restpective shells.
------------------

The 'best' way you can do stuff is to try to find a common ground were command line and graphical shells can live close to one another and benefit from each other. The 'synergy', so to say.

Linux is the best at it out of desktop oriented operating systems go. Some examples:

* X tunnels securely over SSH (even with local 3D acceleration, no less)
* Drag-n-drop from Nautilus to Gnome-terminal.
* xdg-open and gnome-open to launch prefered applications for openning different file types.
* Zenity to launch graphical notifications to scripted events.
* embed command line snippets into launcher icons.

Of course, more things are needed to be done to really get the best of both worlds.

Beginning of the End of text-interface era

Posted Oct 29, 2008 17:10 UTC (Wed) by michich (guest, #17902) [Link]

Command-line is infinately usefull and flexible. It's going _nowhere_.

Of course! Just don't equate command-line with text mode.

Beginning of the End of text-interface era

Posted Nov 3, 2008 10:01 UTC (Mon) by cmsj (guest, #55014) [Link]

"dramatically reduce the ability for common people to perform simple programming tasks"

You've never met a common person, have you ;)

Anyone who is actually likely to drop out of X into a text-mode VT is perfectly capable of hitting Ctrl-Alt-F2. The vast majority of desktop users will basically never ever need to do that (and when they do it's because something about their desktop is screwed up because we failed in some way or another).

This change in Fedora is inconsequential in its impact, but excellent in its progress, and the level of enmity it has generated is hilarious and depressing in equal measure.

Beginning of the End of text-interface era

Posted Oct 29, 2008 18:01 UTC (Wed) by nix (subscriber, #2304) [Link] (1 responses)

Text VTs in graphics mode have been here for a long time. Eventually
they'll become mandatory, I imagine, when graphics cards finally drop the
silicon needed for text mode (probably dropping VGA compatibility at the
same time): Sun workstations have worked this way forever. Thankfully
Linux has supported this for, oh, a decade or more :)

Beginning of the End of text-interface era

Posted Oct 29, 2008 19:08 UTC (Wed) by oak (guest, #2786) [Link]

> Sun workstations have worked this way forever.

Like did the "Unixes" working on the old Amigas (BSD) and Ataris (MiNT)...
Switching to Linux over decade ago seemed kind of regression back then at
least in this regard (and unfortunately KGI didn't get into kernel), but
finally Linux is going to have all the relevant functionality from the old
days by default. :-)

Fedora moves the X server

Posted Oct 29, 2008 15:56 UTC (Wed) by beoba (guest, #16942) [Link] (7 responses)

Makes sense that the graphical interface would go into the first slot, followed by the text interfaces. Never really understood why "7" should be a magic number.

Fedora moves the X server

Posted Oct 29, 2008 18:11 UTC (Wed) by tetromino (guest, #33846) [Link] (6 responses)

Because it makes sense for all the GUI slots to be consecutive. If you are running 4 X servers, you would presumably want them at VT7 .. VT10, and not randomly scattered at VT1, VT9, VT12, and VT-2.7183

Switching one of the X sessions to VT1 just to shave off just a tiny fraction of a second from boot time (and how often do normal linux users boot, anyway? once a month, at the very most?) is, quite frankly, idiotic.

Fedora moves the X server

Posted Oct 29, 2008 20:02 UTC (Wed) by leoc (guest, #39773) [Link] (4 responses)

I bootup my main computer every morning and turn it off at night. What is the point of leaving a desktop machine on all night doing nothing?

Fedora moves the X server

Posted Oct 29, 2008 20:16 UTC (Wed) by niner (subscriber, #26151) [Link] (1 responses)

I do just the same. But I still see a full boot sequence only about once a month thanks
to software suspend. On the notebook suspend to RAM completely eliminates all mode
switching and boot messages.

Fedora moves the X server

Posted Nov 3, 2008 10:05 UTC (Mon) by cmsj (guest, #55014) [Link]

Until this mode-setting jazz is more widely used, suspending and resuming absolutely do involve VT switches. Look for the wickle blinky cursor during both operations.

Fedora moves the X server

Posted Oct 30, 2008 9:55 UTC (Thu) by Tuxie (guest, #47191) [Link]

Building ratio on torrent sites? :)

Fedora moves the X server

Posted Oct 30, 2008 23:02 UTC (Thu) by flewellyn (subscriber, #5047) [Link]

If you also run servers on it?

Fedora moves the X server - yay!

Posted Oct 29, 2008 23:43 UTC (Wed) by PaulWay (guest, #45600) [Link]

Then make the X servers VT1-VT6 and have the text consoles at VT7-VT12. Or whatever. The idea that text consoles have to be first is an arbitrary convention anyway and, as another poster has pointed out, people will find a text console anyway if they want one.

Even if this wasn't possible, I don't think it's the big 'break everything' change you're talking about. People are used to moving windows around on screen - they don't expect to press the button at 47x129 every day. Most Linux people use multiple workspaces but don't always have the same window on the same workspace - they get used to remembering where they last put it. They'll just remember that their graphical terminals - if they have more than one, which, lets face it, is very unlikely - are where they usually put them. Most people habitualise these things fairly quickly so it's hardly likely to cause permanent problems.

And it's not 'a tiny fraction of a second' - in many cases (even on LCD monitors) it can often take two or three seconds to switch video modes and resync. Please try to avoid exaggeration and name-calling in this kind of discussion.

Fedora moves the X server

Posted Oct 29, 2008 16:02 UTC (Wed) by petegn (guest, #847) [Link] (6 responses)

Do i see yet another move by the patheticos to try and kill off the CLI i would suggest those that are affraid of the CLI (((())))) off to the windBloWs world

The CLI is one of the most usefull things in existence so get ya mitts offa it .

Fedora moves the X server

Posted Oct 29, 2008 18:04 UTC (Wed) by nix (subscriber, #2304) [Link] (5 responses)

Text mode (a video adapter property) != command-line interface.

Personally I spend 99.99% of my time in X, mostly so that I get syntax
highlighting and huge numbers of rows and columns in my konsoles: I
imagine most people on non-horribly-constrained hardware do something
similar. I can't imagine why anyone would care what virtual console the X
server is running on...

Fedora moves the X server

Posted Oct 29, 2008 18:17 UTC (Wed) by jzbiciak (guest, #5246) [Link] (2 responses)

I tend to agree. Put the primary interface first. X has become the primary interface for the vast, vast majority of workstations. (I can't really speak for headless servers. I'm a "desktop Linux user.")

As long as I can get to a text console when X gets messed up, then I'm happy. Whether it's Ctrl-Alt-F1 or Ctrl-Alt-F2 doesn't really bother me.

What I don't quite understand is the "speed up" part. Is it that X has to search for an unused TTY and then tell the kernel to switch to it? Can't X just be told what TTY to go to, rather than having to discover it? Or at least patched to skip TTYs that will be dedicated to something other than X?

Fedora moves the X server

Posted Oct 29, 2008 20:06 UTC (Wed) by ianburrell (guest, #47313) [Link] (1 responses)

It takes some video cards and monitors a long time to switch modes when changing virtual terminals. Some of the people on the Fedora mailing list were talking about 3 seconds per switch.

Fedora moves the X server

Posted Oct 30, 2008 14:22 UTC (Thu) by jzbiciak (guest, #5246) [Link]

Here's where I'm confused: How is that a function of switching to VT7? If I start X on VT1 or VT7 or VT493, either way it needs to switch into graphics mode and the monitor needs to resync. That's the source of the 3 second delay, isn't it?

Fedora moves the X server

Posted Oct 29, 2008 19:16 UTC (Wed) by tialaramex (subscriber, #21167) [Link] (1 responses)

Muscle memory is the only good reason I can think of. I cannot even remember explicitly what keys to press, but I know that... aha, I just thought "want text VT" and apparently it was Ctrl-Alt-F1.

Unnecessarily varying things that are in muscle memory is kind of annoying. I don't care enough about this example to make a song and dance, but I can imagine that for some people it seems like their toes are being trodden on.

And yes, a lot of people seem to have got dragged into this by not knowing that VGA text mode is some crazy IBM PS/2 invention, not a venerable Unix tradition, and so its inclusion in Linux is an artefact of Linus' shiny new VGA capable 386 back in 1991 and losing it from Fedora would be as significant as e.g. losing support for the 386 (which yes, already happened). I remember being surprised when I first saw a real Unix workstation (Solbourne I think) crash and scrawl poorly rendered tiny text over its framebuffer, but I got over it, I didn't go out and immediately buy myself a vt320. <insert rambling about Kids These Days...>

Fedora moves the X server

Posted Nov 5, 2008 20:50 UTC (Wed) by roelofs (guest, #2599) [Link]

And yes, a lot of people seem to have got dragged into this by not knowing that VGA text mode is some crazy IBM PS/2 invention

Text mode existed in the very first IBM PCs and in virtually all of the "PCs" that preceded them. It has nothing to do with either VGA or PS/2 beyond continuing to be supported in them (albeit with slightly higher-resolution fonts than most of their predecessors, save only monochrome EGA).

Greg

Fedora moves the X server

Posted Oct 29, 2008 18:33 UTC (Wed) by erwbgy (subscriber, #4104) [Link] (5 responses)

I was bored so I started reading the thread. I stopped when someone said something sensible:

From: Will Woods
Subject: Re: X on tty1 in Rawhide/F10
Newsgroups: gmane.linux.redhat.fedora.devel
Date: 2008-10-28 17:07:00 GMT (1 day, 1 hour and 21 minutes ago)

On Mon, 2008-10-27 at 17:07 -0400, Will Woods wrote:
> Hi folks,
> 
> If you're running F10Beta/Rawhide, you may have noticed already, but I
> wanted to make sure everyone knows this is intentional:
> 
> X HAS MOVED FROM VT7 TO VT1.

OK look. If you absolutely cannot deal with this DRASTIC change in
behavior:

1) add "start on started prefdm" to /etc/event.d/tty1
2) (GNOME) edit /etc/gdm/custom.conf and add
     FirstVT=7
   to the top of the file. Or:
   (KDE) edit /etc/kde/kdm/kdmrc and set
     ServerVTs=-7
     ConsoleTTYs=tty1,tty2,tty3,tty4,tty5,tty6
3) Sigh contentedly at the restoration of your precious tradition.

If you use runlevel 3 + startx, nothing has changed. 

Y'know, it took me all of 10 minutes to figure this out on my own. How
long has this thread gone on? I guess y'all have a lot of free time on
your hands? Because, hey, we've got this release coming out soon - maybe
you could help test it or something?

Just a thought.

-w

p.s.:
https://bugzilla.redhat.com/showdependencytree.cgi?id=F10Preview
https://bugzilla.redhat.com/showdependencytree.cgi?id=F10Blocker
https://bugzilla.redhat.com/showdependencytree.cgi?id=F10Target

Fedora moves the X server

Posted Oct 29, 2008 19:19 UTC (Wed) by gurulabs (subscriber, #10753) [Link] (3 responses)

How is that sensible? We are talking about the DEFAULT behavior. Of course anyone can configure their system anyway they please. That doesn't address the issue of compatibility, consistent, non-determinism, and the fact that the change is NEEDLESS.

As others have noted, the sensible thing to do here is get the fancy/flickerfree/fast bootup while preserving the X server on tty7. They are not mutually exclusive.

Fedora moves the X server

Posted Oct 29, 2008 20:00 UTC (Wed) by rahvin (guest, #16953) [Link] (2 responses)

Everyone's definition of need is different. Personally I consider reductions of seconds of boot time to be very needed. Even 1/2 a second added to other improvements can be very significant and needed. Boot takes far too long and the argument that we shouldn't need to boot very often is nonsensical with the need to conserve energy a paramount in some nations.

Fedora moves the X server

Posted Oct 29, 2008 20:23 UTC (Wed) by niner (subscriber, #26151) [Link] (1 responses)

Want to save energy? Use software suspend! Don't waste time and energy booting.
Want to have faster booting? Do the right thing and use kernel based mode switching.

Fedora moves the X server

Posted Nov 3, 2008 10:19 UTC (Mon) by liljencrantz (guest, #28458) [Link]

Want to seem clever? Read the article before commenting! Don't waste time and energy by switching VT when restoring from suspend.
Want faster suspend/restore? Do the right thing and avoid switching terminals during restore.

Fedora moves the X server

Posted Oct 29, 2008 21:13 UTC (Wed) by dbnichol (subscriber, #39622) [Link]

This is actually not all it takes to remove gdm starting X on VT1. You'd have to stop plymouth from telling gdm to do that. Otherwise, you'd just get X on top of getty.

Fedora moves the X server

Posted Oct 29, 2008 20:52 UTC (Wed) by jrigg (guest, #30848) [Link] (3 responses)

What happens if you don't have X installed? A blank screen on boot up?

Fedora moves the X server

Posted Oct 29, 2008 23:26 UTC (Wed) by bojan (subscriber, #14302) [Link]

I certainly hope not :-)

Fedora moves the X server

Posted Oct 30, 2008 2:59 UTC (Thu) by jmorris42 (guest, #2203) [Link] (1 responses)

> What happens if you don't have X installed? A blank screen on boot up?

From what I have read you would get a login. They adjusted runlevel 5 to not put a getty on tty1 and left the others alone. So if you didn't have X installed you would come up in runlevel 3 and get the expected results. Same if you had problems and came up in single user mode.

Fedora moves the X server

Posted Apr 8, 2009 13:51 UTC (Wed) by marcH (subscriber, #57642) [Link]

Before the change, if X was missing or broken, you would get a text login prompt BY DEFAULT. Not anymore. Now you get a black screen by default. How user-friendly. How bold to assume X will always work.

Fedora moves the X server

Posted Oct 29, 2008 22:17 UTC (Wed) by daniels (subscriber, #16193) [Link] (3 responses)

Every time I make the mistake of reading it, I'm further convinced that fedora-devel-list's raison d'être is to make people feel better about debian-devel.

Fedora moves the X server

Posted Oct 30, 2008 3:39 UTC (Thu) by njs (subscriber, #40338) [Link]

Ha! And just as I was regretting reading all the way through this.

Fedora moves the X server

Posted Oct 30, 2008 23:23 UTC (Thu) by dbnichol (subscriber, #39622) [Link]

I recently subscribed to fedora-devel since I wanted to get more involved in the distro, and I find myself often regretting the decision. It seems "devel" is actually rarely discussed and mostly the list is used for lengthy diatribes about how fedora is ruining people's lives. Try this one on for size: http://thread.gmane.org/gmane.linux.redhat.fedora.devel/93649

That was a good one

Posted Nov 5, 2008 0:23 UTC (Wed) by pr1268 (guest, #24648) [Link]

Every time I make the mistake of reading it, I'm further convinced that fedora-devel-list's raison d'être is to make people feel better about debian-devel.

Thank you--that comment alone just made me not regret having read this far down in the comments. :)

This is kinda stupid, BECAUSE...

Posted Oct 30, 2008 9:05 UTC (Thu) by colo (guest, #45564) [Link]

...it also single-handedly invalidates most tutorials on the web which require you to, for whatever reason, switch to a non-X TTY by pressing "[CTRL]+[ALT]+[F1]".

I don't see any real gain in a move like this. It's somewhere in between an annoyance for the experienced, and a complete show-stopper for newbies.

Correction

Posted Oct 30, 2008 11:32 UTC (Thu) by avik (guest, #704) [Link] (1 responses)

Three lengthy flame wars.

Correction

Posted Oct 31, 2008 19:05 UTC (Fri) by dirtyepic (guest, #30178) [Link]

heh. cute.

Fedora moves the X server

Posted Oct 30, 2008 14:01 UTC (Thu) by smorovic (guest, #52892) [Link] (1 responses)

It's a sound technical decision.

I would like to avoid VT switch on a normal boot. Ideally, X/kernel should initialize graphic card from the bios text mode only once and that now happens with plymouth and X on tty1. If X is started on tty7 (while kernel starts init on tty1), there will be VT switch during the boot process.

Fortunately, with KMS the VT switching (which AFAIK means saving graphic card state and rerunning VGA bios real mode code on x86 machine) goes away even for tty7, but it won't be supported for all common modern graphic hardware for some time (and probably even later for binary drivers).

I support the change. It's just a naming convention and changed shortcut key (that is not mapped by the GUI anyway), not API / ABI incompatibility that would break userspace.

How does Fedora moves the X server?

Posted Nov 2, 2008 10:53 UTC (Sun) by i3839 (guest, #31386) [Link]

You seem like a sensible person who might know more.

Not using Fedora myself and running a heavily modified/tuned distro, you seem the right person to ask the only interesting question which isn't answered anywhere:

How do you tell the X server on which VT to start on?

I start login -f from inittab on tty1, agetties on vc/[234], and Xorg is still using VT 5, not 1. lsof /dev/tty1 shows nothing, while it does show X running on VC 5.

Fedora moves the X server

Posted Oct 30, 2008 23:04 UTC (Thu) by flewellyn (subscriber, #5047) [Link] (1 responses)

Wait...lengthy flamewars about WHAT VT TO START X IN?

Surely they have more important things to do?

Sheesh...why not just edit your inittab (or whatever Upstart uses) to do what you like, protect it from upgrades, and have done with it?

Fedora moves the X server

Posted Oct 31, 2008 0:15 UTC (Fri) by nix (subscriber, #2304) [Link]

This is classic bikeshed-painting. The actually important and interesting
stuff is too complex for J. Random Punter to have an opinion about in ten
seconds, so it doesn't trigger flamewars.