From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next 08/13] net/mlx5e: Add fragmented memory support
 for RX multi packet WQE
Date: Mon, 14 Mar 2016 13:29:46 -0700
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Cc: Saeed Mahameed <saeedm@dev.mellanox.co.il>,
	Saeed Mahameed <saeedm@mellanox.com>,
	"David S. Miller" <davem@davemloft.net>,
	Linux Netdev List <netdev@vger.kernel.org>,
	Or Gerlitz <ogerlitz@mellanox.com>,
	Eran Ben Elisha <eranbe@mellanox.com>,
	Tal Alon <talal@mellanox.com>,
	Tariq Toukan <tariqt@mellanox.com>,
	Jesper Dangaard Brouer <brouer@redhat.com>
To: achiad shochat <achiad.mellanox@gmail.com>
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On Mon, 2016-03-14 at 21:16 +0200, achiad shochat wrote:

> I really do not see why the new scheme is more DOSable than the common
> scheme of pre-allocating SKB using napi_alloc_skb().

Because sizeof(skb_shared_info) is big enough that if you allocate 128
bytes, you end up using 512 bytes or even more.

In practice it is good enough.