From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0E92C6778A for ; Tue, 24 Jul 2018 17:14:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5EA5E20844 for ; Tue, 24 Jul 2018 17:14:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5EA5E20844 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388533AbeGXSVe (ORCPT ); Tue, 24 Jul 2018 14:21:34 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:35054 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388422AbeGXSVe (ORCPT ); Tue, 24 Jul 2018 14:21:34 -0400 Received: from localhost (c-24-20-22-31.hsd1.or.comcast.net [24.20.22.31]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 5D00C108B62A7; Tue, 24 Jul 2018 10:14:06 -0700 (PDT) Date: Tue, 24 Jul 2018 10:14:05 -0700 (PDT) Message-Id: <20180724.101405.797730329231867648.davem@davemloft.net> To: dsahern@gmail.com Cc: xiyou.wangcong@gmail.com, netdev@vger.kernel.org, nikita.leshchenko@oracle.com, roopa@cumulusnetworks.com, stephen@networkplumber.org, idosch@mellanox.com, jiri@mellanox.com, saeedm@mellanox.com, alex.aring@gmail.com, linux-wpan@vger.kernel.org, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC/RFT net-next 00/17] net: Convert neighbor tables to per-namespace From: David Miller In-Reply-To: <5021d874-8e99-6eba-f24b-4257c62d4457@gmail.com> References: <28c30574-391c-b4bd-c337-51d3040d901a@gmail.com> <5021d874-8e99-6eba-f24b-4257c62d4457@gmail.com> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 24 Jul 2018 10:14:06 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Ahern Date: Tue, 24 Jul 2018 09:14:01 -0600 > I get the impression there is no longer a strong resistance against > moving the tables to per namespace, but deciding what is the right > approach to handle backwards compatibility. Correct? Changing the > accounting is inevitably going to be noticeable to some use case(s), but > with sysctl settings it is a simple runtime update once the user knows > to make the change. > > neighbor entries round up to 512 byte allocations, so with the current > gc_thresh defaults (128/512/1024) 512k can be consumed. Using those > limits per namespace seems high which is why I suggested a per-namespace > default of (16/32/64) which amounts to 32k per namespace limit by > default. Open to other suggestions as well. No objection from me about going to per-ns neigh tables. About the defaults, I wonder if we can scale them to the amount of memory given to the ns or something like that? I bet this will better match the intended use of the ns.