From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Zhai, Edwin" <edwin.zhai@intel.com>
Subject: super page with live migration
Date: Fri, 26 Sep 2008 15:45:31 +0800
Message-ID: <20080926074531.GA12042@edwin-srv.sh.intel.com>
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To: Keir <Keir.Fraser@cl.cam.ac.uk>
Cc: xen-devel@lists.xensource.com, "Zhai, Edwin" <edwin.zhai@intel.com>
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Keir,

As you know, we try to allocate super pages in xc_hvm_build for better 
performance in EPT case. But the same logic is missing in xc_domain_restore.

When try to add the logic, I found it is blocked by the lazy populate algorithm 
in restore -- only populating the pages received from source side rather than 
doing it at one time.

So the result is the EPT guest has performance drop after live migration:(

Do you have any plan to change the lazy populate algorithm? The purpose of it, I 
believe, is to make restore process work without guest memory layout knowledge.  

But different memory allocation process may cause some issues, such as perf drop 
after live migration.

Thanks,



-- 
best rgds,
edwin