how-to questions

Adam Lackorzynski adam at
Wed Oct 11 01:22:47 CEST 2006

On Tue Oct 10, 2006 at 09:03:30 +0200, ratko wrote:
> Adam Lackorzynski said:
> >> 2. Where can I see how much memory I can assign to vmlinuz (how much
> >> memory
> >> uses DOpE and L4)?
> >
> > L4Linux can be given the 'mem=xx' option in the loader config file, like
> > in native Linux. With 'L4', do you mean the kernel? The amount of memory
> > taken by the kernel is configured in the kernel itself and is usually
> > some percent of the system memory up to some maximum. Currently it's
> > something around 6%, iirc.
> yes, I know about mem=xx. What i dont know is: what is maximum memory left
> for vmlinuz to use.
> for exmple:
> i have 128mb of memory in PC.
> L4 uses: Xmb
> vmlinuz can use 128mb - Xmb = Ymb
> I tried giving "mem=64" option but (i think DOpE) says it cannot assign
> 64mb to vmlinux. option "mem=50" worked. I don't think it's just a "try
> and see" method, there must be some other way.

DOpE is 'just' a windowing system, the log messages come from the log
server. In your case dm_phys, the memory server, is saying that the
requested allocation cannot be fulfilled as there not enough memory with
the requested attributes left.

dm_phys is also the one to query for remaining memory. When using l4con
the free memory of dm_phys is displayed in the status bar. Otherwise one
could query it with some program.

> >> 4. How can I run more that one Linux process?
> >
> > Easily. Norman already mentioned the 'run' utility. Just start L4Linux
> > another time. You should make sure that the second L4Linux is not
> > touching any hardware the first one is already using, or someone else.
> > Switching off PCI in L4Linux is a good start.
> So new Linux needs another root, swap... seems logical.

Yes. A RAMdisk is quite handy in this case. More advanced setups could
involve ore, our network switch, by e.g. NFS mounting filesystems from a
specific L4Linux instance. There are also other ways possible.

Adam                 adam at

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