tree 140df25fef28c94f9ec1e5c29b4a8d0876da2fe8
parent ad1af0fedba14f82b240a03fe20eb9b2fdbd0357
author Eric Dumazet <eric.dumazet@gmail.com> 1282802537 -0700
committer David S. Miller <davem@davemloft.net> 1282802537 -0700

tcp: fix three tcp sysctls tuning

As discovered by Anton Blanchard, current code to autotune 
tcp_death_row.sysctl_max_tw_buckets, sysctl_tcp_max_orphans and
sysctl_max_syn_backlog makes little sense.

The bigger a page is, the less tcp_max_orphans is : 4096 on a 512GB
machine in Anton's case.

(tcp_hashinfo.bhash_size * sizeof(struct inet_bind_hashbucket))
is much bigger if spinlock debugging is on. Its wrong to select bigger
limits in this case (where kernel structures are also bigger)

bhash_size max is 65536, and we get this value even for small machines. 

A better ground is to use size of ehash table, this also makes code
shorter and more obvious.

Based on a patch from Anton, and another from David.

Reported-and-tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>