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

[Richard W.M. Jones]

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).

Rich.

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