From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: compound skb frag pages appearing in start_xmit
Date: Tue, 09 Oct 2012 16:27:27 +0200
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Cc: Eric Dumazet <edumazet@google.com>,
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To: Ian Campbell <Ian.Campbell@citrix.com>
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On Tue, 2012-10-09 at 15:17 +0100, Ian Campbell wrote:

> Does the higher order pages effectively reduce the number of frags which
> are in use? e.g if MAX_SKB_FRAGS is 16, then for order-0 pages you could
> have 64K worth of frag data.
> 
> If we switch to order-3 pages everywhere then can the skb contain 512K
> of data, or does the effective maximum number of frags in an skb reduce
> to 2?

effective number of frags reduce to 2 or 3

(We still limit GSO packets to ~63536 bytes)