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Date: Wed, 13 Jan 2016 07:44:26 -0800
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Subject: Re: [PATCH] net: add per device sg_max_frags for skb
From: Eric Dumazet <edumazet@google.com>
To: David Miller <davem@davemloft.net>
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On Wed, Jan 13, 2016 at 7:38 AM, David Miller <davem@davemloft.net> wrote:
> From: Eric Dumazet <edumazet@google.com>
> Date: Wed, 13 Jan 2016 06:19:11 -0800
>
>> 2) TCP stack has coalescing support. write(2) or sendmsg(2) should
>> append data into the last skb in write queue, and still use 32 KB
>> frags.
>
> Another way to get pathological SKBs is to do lots of tiny sendpage()
> calls over discontiguous areas of the file.

Yes, this was what I mentioned in the following sentence.
"You get pathological skb when using sendpage() or ..."