From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Magenheimer <dan.magenheimer@oracle.com>
Subject: Even faster page copy for Xen?
Date: Thu, 15 Jul 2010 11:15:46 -0700 (PDT)
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To: Keir Fraser <keir.fraser@eu.citrix.com>, Jan Beulich <JBeulich@novell.com>
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Hi Jan, Keir --

My x86 assembly skills are much too poor to carefully evaluate
and, if of value, implement this in Xen but given your previous
interest, such as:

http://xenbits.xensource.com/xen-unstable.hg?rev/8de4b4e9a435=20

the following might be worth looking at.

Intel has just posted memcpy improvements for glibc for recent
popular Intel processor families here:

http://article.gmane.org/gmane.comp.lib.glibc.alpha/15278=20

The preface to the above patch looks very enticing...

Semi-related, I wonder if you know, if there were a
"copy_page_from_other_node()" to be used if the
caller is fairly sure that the page is being copied
between nodes, could this be made significantly faster
than a normal copy_page()?

Thanks,
Dan