From: David Ahern <dsahern@gmail.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>,
David Miller <davem@davemloft.net>,
Linux Kernel Network Developers <netdev@vger.kernel.org>,
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,
NetFilter <netfilter-devel@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to per-namespace
Date: Wed, 25 Jul 2018 12:13:30 -0600 [thread overview]
Message-ID: <dacc9322-fd5a-dfeb-e4f1-7a288fb79886@gmail.com> (raw)
In-Reply-To: <87zhyfw70m.fsf@xmission.com>
On 7/25/18 11:38 AM, Eric W. Biederman wrote:
>
> Absolutely NOT. Global thresholds are exactly correct given the fact
> you are running on a single kernel.
>
> Memory is not free (Even though we are swimming in enough of it memory
> rarely matters). One of the few remaining challenges is for containers
> is finding was to limit resources in such a way that one application
> does not mess things up for another container during ordinary usage.
>
> It looks like the neighbour tables absolutely are that kind of problem,
> because the artificial limits are too strict. Completely giving up on
> limits does not seem right approach either. We need to fix the limits
> we have (perhaps making them go away entirely), not just apply a
> band-aid. Let's get to the bottom of this and make the system better.
Eric: yes, they all share the global resource of memory and there should
be limits on how many entries a remote entity can create.
Network namespaces can provide a separation such that one namespace does
not disrupt networking in another. It is absolutely appropriate to do
so. Your rigid stance is inconsistent given the basic meaning of a
network namespace and the parallels to this same problem -- bridges,
vxlans, and ip fragments. Only neighbor tables are not per-device or per
namespace; your insistence on global limits is missing the mark and wrong.
next prev parent reply other threads:[~2018-07-25 19:26 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-17 12:06 [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to per-namespace dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 01/17] net/ipv4: rename ipv4_neigh_lookup to ipv4_dst_neigh_lookup dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 02/17] net/neigh: export neigh_find_table dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 03/17] net/ipv4: wrappers for arp table references dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 04/17] net/ipv4: Remove open coded use of arp table dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 05/17] net/ipv6: wrappers for neighbor table references dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 06/17] net/ipv6: Remove open coded use of neighbor table dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 07/17] drivers/net: remove open coding of neighbor tables dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 08/17] net: Remove nd_tbl from ipv6 stub dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 09/17] net: Remove arp_tbl and nd_tbl from headers dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 10/17] net: Add key_len to neighbor constructor dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 11/17] net: Change neigh_table_init and neigh_table_clear signature dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 12/17] net/neigh: Change neigh_xmit to take an address family dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 13/17] net/neighbor: Convert internal functions away from neigh_tables dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 14/17] net/ipv4: Convert arp table to per namespace dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 15/17] net/ipv6: Convert neighbor table to per-namespace dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 16/17] net/decnet: Move " dsahern
2018-07-17 12:06 ` [PATCH RFC/RFT net-next 17/17] net/neighbor: Remove neigh_tables and NEIGH enum dsahern
2018-07-17 17:40 ` [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to per-namespace Cong Wang
2018-07-17 17:43 ` David Ahern
2018-07-17 17:53 ` Cong Wang
2018-07-17 19:02 ` David Ahern
2018-07-17 20:37 ` Cong Wang
2018-07-18 3:59 ` David Miller
2018-07-19 16:16 ` David Ahern
2018-07-19 17:12 ` Cong Wang
2018-07-24 15:14 ` David Ahern
2018-07-24 17:14 ` David Miller
2018-07-25 18:23 ` David Ahern
2018-07-24 22:09 ` Cong Wang
2018-07-25 12:33 ` Eric W. Biederman
2018-07-25 14:06 ` David Ahern
2018-07-25 17:38 ` Eric W. Biederman
2018-07-25 18:13 ` David Ahern [this message]
2018-07-25 19:17 ` Eric W. Biederman
2018-08-13 21:48 ` David Ahern
2018-08-15 4:36 ` Eric W. Biederman
2018-07-26 11:12 ` David Laight
2018-07-27 16:27 ` Eric W. Biederman
2018-07-19 0:54 ` Michael Richardson
2018-07-19 15:49 ` David Ahern
2018-08-12 6:46 ` [RFC/RFT, net-next, " Vasily Averin
2018-08-12 17:37 ` David Ahern
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=dacc9322-fd5a-dfeb-e4f1-7a288fb79886@gmail.com \
--to=dsahern@gmail.com \
--cc=alex.aring@gmail.com \
--cc=davem@davemloft.net \
--cc=ebiederm@xmission.com \
--cc=idosch@mellanox.com \
--cc=jiri@mellanox.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-wpan@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=netfilter-devel@vger.kernel.org \
--cc=nikita.leshchenko@oracle.com \
--cc=roopa@cumulusnetworks.com \
--cc=saeedm@mellanox.com \
--cc=stephen@networkplumber.org \
--cc=xiyou.wangcong@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).