Re: [Qemu-devel] Anyone seeing huge slowdown launching qemu with Linux 2.6.35?

[Gleb Natapov]

On Wed, Aug 04, 2010 at 12:33:18PM +0100, Richard W.M. Jones wrote:
> On Wed, Aug 04, 2010 at 12:52:23PM +0300, Avi Kivity wrote:
> >  On 08/04/2010 12:24 PM, Richard W.M. Jones wrote:
> > >>>
> > >>>Just like the initrd?
> > >>There isn't enough address space for a 100MB initrd in ROM.
> > >Because of limits of the original PC, sure, where you had to fit
> > >everything in 0xa0000-0xfffff or whatever it was.
> > >
> > >But this isn't a real PC.
> > >
> > >You can map the read-only memory anywhere you want.
> > 
> > I wasn't talking about the 1MB limit, rather the 4GB limit.  Of
> > that, 3-3.5GB are reserved for RAM, 0.5-1GB for PCI.  Putting large
> > amounts of ROM in that space will cost us PCI space.
> 
> I'm only allocating 500MB of RAM, so there's easily enough space to
> put a large ROM, with tons of room for growth (of both RAM and ROM).
> Yes, even real hardware has done this.  The Weitek math copro mapped
> itself in at physical memory addresses c0000000 (a 32 MB window IIRC).
> 
c0000000 is 3G. This is where PCI windows starts usually  (configurable
in the chipset). Don't see anything unusual in this particular HW.

--
                        Gleb.