Message-ID: <1439401585.29802.15.camel@edumazet-glaptop2.roam.corp.google.com>
Subject: Re: [PATCH] net: Use SK_MEM_QUANTUM as minimum for tcp/udp rmem/wmem
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Sorin Dumitru <sorin@returnze.ro>
Cc: Calvin Owens <calvinowens@fb.com>, Sorin Dumitru <sdumitru@ixiacom.com>,
        David Miller <davem@davemloft.net>, kuznet@ms2.inr.ac.ru,
        jmorris@namei.org, yoshfuji@linux-ipv6.org, kaber@trash.net,
        netdev <netdev@vger.kernel.org>, linux-kernel@vger.kernel.org,
        kernel-team@fb.com
Date: Wed, 12 Aug 2015 10:46:25 -0700
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On Wed, 2015-08-12 at 20:00 +0300, Sorin Dumitru wrote:

> Would clamping the values to a min value, like setsockopt(SO_SNDBUF)
> does, be an option?
> I still find it odd that SO_SNDBUF limits you, while the /proc
> interface doesn't. If you think it's
> too much, I'm ok with reverting it since it affects scripts.
> 
> On those arches where PAGE_SIZE == 64K(or > 16K) it looks like we have
> tcp_wmem[1]
> smaller than tcp_wmem[0]. Shouldn't we do something about this?

As long as we do not crash if/when root user changes /proc/sys/net
settings, we are good.

I would not care if performance is bad if root does something really
stupid. root user is supposed to not mess things just for fun.


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