Dave Hansen wrote:
On Tue, 2005-02-15 at 04:50 -0600, Robin Holt wrote:
What is the fundamental opposition to an array from from-to node mappings?
They are not that difficult to follow. They make the expensive traversal
of ptes the single pass operation. The time to scan the list of from nodes
to locate the node this page belongs to is relatively quick when compared
to the time to scan ptes and will result in probably no cache trashing
like the long traversal of all ptes in the system required for multiple
system calls. I can not see the node array as anything but the right way
when compared to multiple system calls. What am I missing?
I don't really have any fundamental opposition. I'm just trying to make
sure that there's not a simpler (better) way of doing it. You've
obviously thought about it a lot more than I have, and I'm trying to
understand your process.
As far as the execution speed with a simpler system call. Yes, it will
likely be slower. However, I'm not sure that the increase in scan time
is all that significant compared to the migration code (it's pretty
slow).
-- Dave
I'm worried about doing all of those find_get_page() things over and over
when the mapped file we are migrating is large. I suppose one can argue
that that is never going to be the case (e. g. no one in their right mind
would migrate a job with a 300 GB mapped file). So we are back to the
overlapping set of nodes issue. Let me look into this some more.
--
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Ray Bryant
512-453-9679 (work) 512-507-7807 (cell)
[EMAIL PROTECTED] [EMAIL PROTECTED]
The box said: "Requires Windows 98 or better",
so I installed Linux.
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