[CLUE-Tech] (In)Stability of X?

[Michael J. Hammel]

Thus spoke Matt Gushee
> 3.3.6 -- I tried to install 4.1 a couple months ago, but found out it
> didn't support my video card except in lo-res VGA mode ... not sure I
> understand that ...

The architecture between 3.3.x and 4.x changed drastically.  All low level
code had to be rewritten.  Because the expertise for some cards was no longer
part of the XFree86 team and the current team didn't have either specs or
cards to test with, some older 3.3.x supported cards were dropped in 4.x.
The team didn't want to do that, of course.  It was just a matter of
available resources.

> On the other hand, I have a Dell Inspiron 3500 laptop from work. It has
> a neomagic chipset (I forget which model exactly -- who can keep track?)
> and is running XF86 4.1. When in the office, I have typically used it
> hooked up to an external LCD monitor. When I use it standalone, it 
> occasionally locks up, but hooked up to the external monitor, it locks
> up almost every day, sometimes several times a day. This especially 
> happens when I use KDE apps (or should I say QT? dunno -- I don't really
> use non-KDE QT apps), and Konqueror is certain death.

I'm willing to be this isn't just the X driver, but a combination of that
driver with a strange set of integrated components on your laptop.  Laptops
are notorious for mixing hardware components, requiring specialized drivers
to make sure they work properly.  That's why laptops have been more
problematic to support for Linux in the past than desktop machines.

> My usual window manager on both machines is Window Maker, though I some-
> times run others -- and though I sometimes run KDE apps, I don't use
> the full desktop.

Probably irrelevant.  Lock ups tend to be related to hardware access.
Applications don't usually do much of that unless your using a CD burner or
DVD player or maybe an audio card at the same time.  Window manager lockups
can usually be cleared by killing X without a hardware reboot.

> However, I suspect this is really more of a hardware issue, because:
> 
>  * If I turn off the built-in monitor from the keyboard, after a while
>    it comes back on by itself.
>  * The problem becomes less severe (but doesn't vanish) if I set the
>    BIOS to 'external monitor' (as opposed to auto-detect).
>  * When I started getting fed up with it, I tried SSHing in from another
>    machine and killing X. Killed XFree86, xinit, startx, anything I
>    could think of having to do with X, and double-checked with 'ps aux'
>    that they were dead. The image on the screen remained frozen, and
>    the keyboard continued to be completely dead.

Sounds like a funky component issue.

> Seems like certain GUI apps are dangerous: I mentioned KDE above; I
> also recall that several years ago, when I first started using the
> GIMP (version 0.99?), I had very frequent lockups: what would happen
> was that when there was an exception, the GIMP would write a message
> to the console, with a prompt for the user to make a choice ... and
> block waiting for input, effectively locking the X session. It still
> happens once in a while.

That can be disabled at build time, I believe, in current versions.  It's a
debugging tool for developers, so it shouldn't be turned on in end-user
distributables.

> Then there's Netscape 4.x. No doubt everybody's got their own horror
> story, so I won't go on at length. But sometimes I browse Japanese 
> sites, using TrueType fonts for the Japanese characters. For the first
> few pages, and sometimes later ones (I suppose until most of the 
> characters are cached), Netscrape takes a LONG, LONG time (2-3 minutes
> sometimes) to render a page, and everything else freezes until it's done.

Netscapes font renderer is pretty ugly.  It will cause X lock ups on
ocassion, but not the kind that tend to require hardware reboots (the
renderer gets stuck in a spin loop, usually, but that's different than a
hardware corruption).  I tend to avoid Java sites and sites that make use of
heavy Javascript and/or sites that pop open new windows (geocities and the
ilk).  I'd switch to the newer browsers (Galeon, Mozilla, etc.), but most of
those have their own problems.  

-- 
Michael J. Hammel           |
The Graphics Muse           |  I'd explain it to you, but your brain would 
mjhammel at graphics-muse.org  |  explode.  -- Dilbert
http://www.graphics-muse.com