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Re: [Xen-devel] Re: how to avoid lost trace records?

To: George Dunlap <dunlapg@xxxxxxxxx>
Subject: Re: [Xen-devel] Re: how to avoid lost trace records?
From: Olaf Hering <olaf@xxxxxxxxx>
Date: Mon, 22 Nov 2010 13:40:15 +0100
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On Mon, Nov 22, George Dunlap wrote:

> Olaf,
> 
> Dang, 8 megs per cpu -- but I guess that's really not so much overhead
> on a big machine; and it's definitely worth getting around the lost
> records issue.  Send the T_INFO_PAGES patch to the list, and see what
> Keir thinks.

Yes, will do.

Sometimes there is a boost of records, like set_p2m_entry and the like.
They all happen on the same cpu, so the per_cpu buffer fills up quickly.
And thats what I'm debugging right now. Too bad, tracing adds overhead
so the bug disappears. So, back to reading source code and find the race
that way.

Olaf

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