From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shan Wei <shanwei88@gmail.com>
Subject: [BUG report] net.core.rmem_default is larger than net.core.rmem_max
Date: Fri, 27 Apr 2012 17:31:22 +0800
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Cc: NetDev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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It's unconventional that "default" value  is greater than "max". :-(

net.core.rmem_max = 131071
net.core.rmem_default = 229376

net.core.wmem_max = 131071
net.core.wmem_default = 229376


And bisect the code to find the following commit caused this phenomenon.
This patch increase SK_WMEM_MAX and SK_RMEM_MAX which are used to 
initialize them.
But rmem_max and wmem_max value are still be covered according the RAM size
in sk_init().

87fb4b7b533073eeeaed0b6bf7c2328995f6c075 is the first bad commit
commit 87fb4b7b533073eeeaed0b6bf7c2328995f6c075
Author: Eric Dumazet <eric.dumazet@gmail.com>
Date:   Thu Oct 13 07:28:54 2011 +0000

    net: more accurate skb truesize