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Re: [Xen-users] Vanishing memory? Whats going on?

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] Vanishing memory? Whats going on?
From: bleomycin <diabolical@xxxxxxxxx>
Date: Sat, 5 Jul 2008 20:43:24 -0700 (PDT)
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John Haxby-3 wrote:
> 
> 
> What you're looking at with "free -m" is, I would imagine, the memory 
> available to dom0 and that would make sense as the hypervisor takes a 
> slice and then each domU takes 0.5GB leaving you with just shy of 3GB.
> 
> If you can't create a third domU then its because the balloon driver in 
> dom0 can't reclaim enough memory to start the new domain: generally 
> speaking the balloon driver will "acquire" memory from the cache.
> 
> You could try setting dom0_mem=1024M (for example) on the kernel command 
> line in grub  (there's a kernel line and a couple of module lines 
> normally).   That will leave you with just short of 3GB for guests.
> 
> Oh, and if you have the choice then go for pv guests rather than hvm 
> because having a kernel that knows its in a virtual environment is 
> generally an advantage.
> 
> jch
> 
> _______________________________________________
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> 
> 

Thank you very much for the reply. I must not fully understand the point of
hvm. Other than being used to run windows, I thought hvm was required to
take full advantage of intel/amd's VT technology built into the newer
processors? Or is that handled automatically regardless of hvm?
-- 
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http://www.nabble.com/Vanishing-memory--Whats-going-on--tp18269784p18298577.html
Sent from the Xen - User mailing list archive at Nabble.com.


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