From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Laight <David.Laight@ACULAB.COM>
Subject: RE: [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to
 per-namespace
Date: Thu, 26 Jul 2018 11:12:34 +0000
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Cc: Cong Wang <xiyou.wangcong@gmail.com>,
        David Miller <davem@davemloft.net>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        "nikita.leshchenko@oracle.com" <nikita.leshchenko@oracle.com>,
        Roopa Prabhu <roopa@cumulusnetworks.com>,
        Stephen Hemminger <stephen@networkplumber.org>,
        Ido Schimmel <idosch@mellanox.com>,
        Jiri Pirko <jiri@mellanox.com>,
        "Saeed Mahameed" <saeedm@mellanox.com>,
        Alexander Aring <alex.aring@gmail.com>,
        "linux-wpan@vger.kernel.org" <linux-wpan@vger.kernel.org>,
        NetFilter <netfilter-devel@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
To: "'Eric W. Biederman'" <ebiederm@xmission.com>,
        David Ahern <dsahern@gmail.com>
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From: Eric W. Biederman
> Sent: 25 July 2018 18:38
...
> >> Further unless I misread something you are increasing the number of
> >> timers to 3 per namespace.  If I create create a thousand network
> >> namespaces that feels like it will hurt system performance overall.
> >
> > It seems to me the timers are per neighbor entry not table. The per
> > table ones are for proxies.
> 
> It seems I misread that bit when I was refreshing my memory on what
> everything is doing.  If we can already have 1024 timers that makes
> timers not a concern.

Surely it is enough to just have a timestamp in each entry.
Deletion of expired items need not be done until insert (which
has the table suitable locked) bumps into an expired item.

	David

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