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From: Michael Neuling <mikey@neuling.org>
To: Paul Mackerras <paulus@samba.org>
Subject: Re: [PATCH 2/2] powerpc,kexec: Speedup kexec hpte tear down
In-reply-to: <20100512010003.GB3548@drongo>
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Date: Wed, 12 May 2010 11:06:58 +1000
Message-ID: <9537.1273626418@neuling.org>
Cc: linuxppc-dev@ozlabs.org, kexec@lists.infradead.org,
	Anton Blanchard <anton@samba.org>
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> > We probably only do the remove on < 1% of the hptes now.  So I doubt we
> > would get a speedup since most of the time we aren't do the remove
> > anymore.
> 
> It would be nice to have some actual numbers.  Could you add some
> counters and print the results at the end?  (Or don't you have any
> way to print things at that stage?)

Printing is hard at that point but I think we can do it.  I'll try to
when I get some time.

A heavily loaded system which kdumps will need a lot more hptes removes
than kexec, so stats for both these cases might be useful also.

Mikey