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From: "H. Peter Anvin" <hpa@zytor.com>
To: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: akpm@linux-foundation.org, containers@lists.linux-foundation.org,
	bblum@google.com, linux-kernel@vger.kernel.org,
	menage@google.com, vda.linux@googlemail.com, mikew@google.com
Subject: Re: [RFCv2][PATCH] flexible array implementation
Date: Wed, 22 Jul 2009 19:45:11 -0700	[thread overview]
Message-ID: <4A67CEB7.2080505@zytor.com> (raw)
In-Reply-To: <20090721220017.60A219D3@kernel>

On 07/21/2009 03:00 PM, Dave Hansen wrote:
> 
> Here's an alternative.  I think it's what Andrew was
> suggesting  here:
> 
> 	http://lkml.org/lkml/2009/7/2/518 
> 
> I call it a flexible array.  It does all of its work in
> PAGE_SIZE bits, so never does an order>0 allocation.
> The base level has PAGE_SIZE-2*sizeof(int) bytes of
> storage for pointers to the second level.  So, with a
> 32-bit arch, you get about 4MB (4183112 bytes) of total
> storage when the objects pack nicely into a page.  It
> is half that on 64-bit because the pointers are twice
> the size.
> 

I'm wondering if there is any use case which would require scaling below
the PAGE_SIZE level... in which case it would be nice for it to
gracefully decay to a single kmalloc allocation + some metadata.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.


  parent reply	other threads:[~2009-07-23  2:46 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-21 22:00 [RFCv2][PATCH] flexible array implementation Dave Hansen
2009-07-21 22:09 ` Dave Hansen
2009-07-21 22:35   ` Andrew Morton
2009-07-22  3:25 ` Li Zefan
2009-07-22  4:34   ` Dave Hansen
2009-07-22  6:14     ` Li Zefan
2009-07-22  7:09 ` Amerigo Wang
2009-07-22 15:02   ` Dave Hansen
2009-07-22 18:30 ` Matt Helsley
2009-07-22 22:03   ` Dave Hansen
2009-07-22 19:55 ` Mike Waychison
2009-07-22 22:00   ` Dave Hansen
2009-07-22 20:57 ` Benjamin Blum
2009-07-22 21:51   ` Dave Hansen
2009-07-22 23:20     ` Benjamin Blum
2009-07-23  5:41       ` Dave Hansen
2009-07-23  2:45 ` H. Peter Anvin [this message]
2009-07-23 14:30   ` Dave Hansen

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