[A83] Re: Me so curious [OT]

[Prev][Next][Index][Thread]

[A83] Re: Me so curious [OT]


Ronald Teune writes:
> Heh, or if Microsoft ported windoze to it :-P
> By the way, in Holland M$ is broadcasting commercials something like
> this: "blah blah Computers always hang on the wrong moment blah blah
> Now there's reliable software: Microsofs Windows XP Proffesional and
> Microsoft Office XP Proffesional"

And they would be correct.  Compared to the Windows 95 line, Windows XP is
_very_ stable.

> Well, Microsoft, good OSes are there since there were good computers.
> Anyway, is the OS really changed? One day I heard that in windoze all
> programs are hooked in the OS core, so if one program crashes, it
> takes everything down. In Linux everything would be free and not
> hooked into eachother, so if a program crashes, only the program
> itself crashes. Is this also the case in NT/XP? Or is the commercial
> lying... lie-ing, well, I mean "it lies".
> I really had to say this. :-)

That is basically correct about Windows 95, although I would not base my
knowledge on something "I heard".  Windows NT is a "real operating system"
like Linux or FreeBSD.  Programs are separate from each other and in theory,
one program should not be able to crash another program.

There are few issues that cause problems with this.  The first is the
interface problem.  If a program manages to lock up the GUI (like a full
screen app) then the OS may be running fine, but you won't have any way to
access it to terminate the offending program.  The exact same thing can
happen on Linux with XFree86.  The advantage there is that you can usually
access it remotely via SSH to terminate the X server.  On Windows, which
doesn't have such remote control capabilities by default, there isn't much
you can do besides restarting it.  With Cygwin, you can run an SSH server as
a service.  This, combined with other process related tools like "ps" and
"kill", can save you in such circumstances.

There is also the issue of resource exhaustion.  Things like "fork bombs",
which start a huge number of processes, can keep you from being able to use
the system.  If the system can't start any more processes, then you can't
login remotely, because the SSH server won't be able to fork a process to
start a shell.  You may be logged in already and have a shell prompt, but
the shell won't be able to fork a process to execute a command (like
"killall").  Of course, UNIX has resource limits to deal with such
situations.

Drivers are a big issue with OS stability.  The biggest reason why the
Windows 95 line is perceived as being so unstable is due to bad drivers.
Drivers have root access to the machine.  A bug in a driver can easily crash
the entire machine.  With so many third party devices with lousy drivers, is
it any wonder why Windows 95 crashes so often for so many people?  There are
ways to deal with this problem.  It is possible to have an OS that will run
fine with buggy drivers.  However, I don't know of any available operating
systems that take this route.  Windows NT, Linux and FreeBSD will all crash
if a driver is buggy.  This is due to the driver essentially being part of
the kernel.

--
David Phillips <david@acz.org>
http://david.acz.org/
References: