From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] tcp: use order-3 pages in tcp_sendmsg()
Date: Thu, 15 Nov 2012 05:47:26 -0800
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To: "Yan, Zheng" <yanzheng@21cn.com>
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On Thu, 2012-11-15 at 15:52 +0800, Yan, Zheng wrote:
> LLC misses happen on the receiver size. It means most pages allocated by the
> senders are cache hot. But when using order-3 pages, 2048 * 32k = 64M, 64M
> is much larger than LLC size.

By the way, this 2048*32k is wrong, as the receiver only uses fragments
in pages, and its not related to the "tcp: use order-3 pages in
tcp_sendmsg()" commit

Many drivers use order-0 pages to hold ethernet frames, regardless of
what was used by the sender ;)