[uml-user] Question about UML stability

[Stefan H. <she...@or...>]

Hello!

First of all let me say that I think you all do a great job with User Mode =

Linux. I read and heard so many good things about it that I simply had to=20
give it a shot and set up a test environment with several different virtual=
=20
Linux machines running on the same host (planned: AMD Athlon system with a
60 GB harddrive and 1 GB of RAM, right now: Pentium III/667 with 384 MB of =

RAM for testing it). But I ran into stability problems, mainly while bootin=
g=20
up the virtual machines...

This might seem to sound like an odd question to you but I have to ask=20
anyway... Can you give me any indication of how stable you think User Mode =

Linux is right now? I am asking because I was trying to set it up for the=20
last two days but I got a lot of Kernel panics and other errors during boot=
.=20
Sometimes it worked fine (probably 3 out of 10 times I booted) and I was ab=
le=20
to set up networking etc. but most of the time I get messages like these:

-> Kernel mode fault at addr 0x7, ip 0x1001949a
-> insert=5Fvm=5Fstruct: tree inconsistent with list
-> segfault with no mm
-> kernel BUG at dcache.c:654
and so on.

Right now my system's configuration is as follows:

SuSE 7.1 host with an unchanged Kernel 2.2.18, using ext2 on the UML=20
partition. UML Kernel version 2.4.4-1um (I tried 2.4.5 but it crashed even =

more often). I used the RPM of that published on your page.

I tried different root filesystems that you have on SourceForge like=20
root=5Ffs=5Fmandrake=5F7.1=5Fbig.bz2, root=5Ffs=5Fredhat=5F7.0=5Fbig.bz2, a=
nd=20
deb-package-2.4.4.tar.bz2 where the debian installation worked best but is =

very small. I also installed Mandrake 8.0 and created my own root filesyste=
m=20
out of it. It sometimes works fine as well, sometimes...

I have to admit that I didn't want to patch my host's Kernel so I had to us=
e=20
SLIP (umn) networking which I got to work but only in the rare case that th=
e=20
systems booted up at all... Here's my command line I use to boot up the=20
system(s):

linux ubd0=3D./redhat70=5Fbig ubd1=3D./swap256 mem=3D256m umn=3D192.168.201=
.65

So, please now feel free to start hitting on me :-). Is there anything I=20
missed entirely? Is stability really that bad or is it just me? Does it eve=
n=20
make sense to try it again or am I forced to give it a rest and use VMware =

instead to run my virtual test servers?

I would love to use UML, that's why I am asking. If you say that stability =
is=20
usually much better than I experienced in the past two days I will sure giv=
e=20
it another try so in return for your help I can provide you with feedback o=
n=20
how UML is doing on a machine with 1 GB of RAM and several instances of UML=
=20
running at the same time and on high load. How does that sound?! :-)

Many thanks in advance for any answers.

Regards, Stefan.