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From: "Y. D." <duyuyang@gmail.com>
To: xen-devel <xen-devel@lists.xensource.com>
Subject: Different: nr_pages vs. max_pfn
Date: Wed, 19 Nov 2008 17:45:50 +0800	[thread overview]
Message-ID: <200811191745479618049@gmail.com> (raw)

Hi,

In start_info, there is a field nr_pages definig how much memory is allocated to the domain, which is obvious.
While in shared_info, there is a field max_pfn. I don't know why max_pfn is not equal to nr_pages.
Say for 32MB memory, nr_pages = 8192, while max_pfn = 10240 (may vary?), of which 2048 pfn's have invalid mfn.
Can anybody explain that why max_pfn is larger? Is it static or dynamic?
Furture, does pfn to mfn frame mapping ever change? Hopefully not.

Thanks,
Shawn

             reply	other threads:[~2008-11-19  9:45 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-19  9:45 Y. D. [this message]
2008-11-19  9:54 ` Different: nr_pages vs. max_pfn Keir Fraser
2008-11-19 10:23   ` Jayaraman, Bhaskar
2008-11-19 12:22   ` Y. D.

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