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From: John Baldwin <jhb@freebsd.org>
To: freebsd-net@freebsd.org
Subject: Re: Use of contiguous physical memory in cxgbe driver
Date: Tue, 11 Feb 2014 13:48:51 -0500
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 (bigwig.baldwin.cx); Tue, 11 Feb 2014 14:49:51 -0500 (EST)
Cc: Adrian Chadd <adrian@freebsd.org>, Garrett Wollman <wollman@freebsd.org>,
 Navdeep Parhar <np@freebsd.org>, "net@freebsd.org" <net@freebsd.org>
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On Thursday, January 23, 2014 2:32:51 am Adrian Chadd wrote:
> It's about time we taught the physmem allocator to be more conducive
> to physically contiguous allocations.
> 
> A server with gigabytes of memory should be able to keep a couple tens
> of megabytes of 64k sized allocation chunks around for exactly this.

Alan Cox already taught the physmem allocator to do this for superpages.  
However, this change was part of the superpages changes, so you can't count 
experiences from machines older than about 7.2 when evaluating the 
effectiveness of the new allocator.

-- 
John Baldwin