Message-ID: <43DDE8D1.6060503@cosmosbay.com>
Date: Mon, 30 Jan 2006 11:22:09 +0100
From: Eric Dumazet <dada1@cosmosbay.com>
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To: "David S. Miller" <davem@davemloft.net>
CC: bcrl@kvack.org, akpm@osdl.org, linux-kernel@vger.kernel.org
Subject: Re: Questions about alloc_large_system_hash() and TLB entries
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David S. Miller a ?crit :
> From: Eric Dumazet <dada1@cosmosbay.com>
> Date: Mon, 30 Jan 2006 10:03:40 +0100
> 
>> What would be the needed changes in the code to get both :
>>
>>    - Allocate ram equally from all the nodes of the machine
>>
>>    - Use large pages (2MB) to lower TLB stress
> 
> These two desires are mutually exclusive, I think.
> 
> If you want an 8MB hash table, for example, with 2MB mappings
> you could use memory from a maximum of 4 nodes since the
> 2MB chunks have to be physically 2MB aligned and 2MB contiguous.

Yes of course, but as those hash tables are very big (their size is bigger 
than 2MB * number_of_nodes if you have at least 4GB per node), this could be 
done ?

Eric

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