Re: [Anima] ANIMA when there is a system-wide issue

Michael Richardson <mcr+ietf@sandelman.ca> Mon, 30 November 2020 23:36 UTC

Return-Path: <mcr+ietf@sandelman.ca>
X-Original-To: anima@ietfa.amsl.com
Delivered-To: anima@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 5AD5B3A1077 for <anima@ietfa.amsl.com>; Mon, 30 Nov 2020 15:36:20 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4inanfqQIv9I for <anima@ietfa.amsl.com>; Mon, 30 Nov 2020 15:36:18 -0800 (PST)
Received: from tuna.sandelman.ca (tuna.sandelman.ca [IPv6:2607:f0b0:f:3:216:3eff:fe7c:d1f3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 37BC03A1044 for <anima@ietf.org>; Mon, 30 Nov 2020 15:36:17 -0800 (PST)
Received: from localhost (localhost [127.0.0.1]) by tuna.sandelman.ca (Postfix) with ESMTP id 83189389A2; Mon, 30 Nov 2020 18:37:59 -0500 (EST)
Received: from tuna.sandelman.ca ([127.0.0.1]) by localhost (localhost [127.0.0.1]) (amavisd-new, port 10024) with LMTP id G159X4S7rv-I; Mon, 30 Nov 2020 18:37:59 -0500 (EST)
Received: from sandelman.ca (obiwan.sandelman.ca [IPv6:2607:f0b0:f:2::247]) by tuna.sandelman.ca (Postfix) with ESMTP id 22FCE389A1; Mon, 30 Nov 2020 18:37:59 -0500 (EST)
Received: from localhost (localhost [IPv6:::1]) by sandelman.ca (Postfix) with ESMTP id 9A99F71C; Mon, 30 Nov 2020 18:36:16 -0500 (EST)
From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
cc: Anima WG <anima@ietf.org>
In-Reply-To: <136aa329-41a5-8b65-ef9e-fadf089696eb@gmail.com>
References: <136aa329-41a5-8b65-ef9e-fadf089696eb@gmail.com>
X-Mailer: MH-E 8.6+git; nmh 1.7+dev; GNU Emacs 26.1
X-Face: $\n1pF)h^`}$H>Hk{L"x@)JS7<%Az}5RyS@k9X%29-lHB$Ti.V>2bi.~ehC0; <'$9xN5Ub# z!G,p`nR&p7Fz@^UXIn156S8.~^@MJ*mMsD7=QFeq%AL4m<nPbLgmtKK-5dC@#:k
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature"
Date: Mon, 30 Nov 2020 18:36:16 -0500
Message-ID: <29097.1606779376@localhost>
Archived-At: <https://mailarchive.ietf.org/arch/msg/anima/XHpnebd146BkqjfGrNtOtlpOOOA>
Subject: Re: [Anima] ANIMA when there is a system-wide issue
X-BeenThere: anima@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Autonomic Networking Integrated Model and Approach <anima.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/anima>, <mailto:anima-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/anima/>
List-Post: <mailto:anima@ietf.org>
List-Help: <mailto:anima-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/anima>, <mailto:anima-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 30 Nov 2020 23:36:20 -0000

Brian E Carpenter <brian.e.carpenter@gmail.com> wrote:
    > Perhaps there is something we should specify in ANIMA to prevent the
    > ANIMA infrastructure falling into this sort of trap: when there is a
    > system-wide issue (such as hitting an O/S resource limit everywhere at
    > the same time) it also prevents the autonomic mechanisms from working.

I think you mean, that it should not also prevent the autonomic system?
I think that key is:
  1) allocate resources (including threads) up-front
  2) do not dynamically allocate threads per interface, but rather use async
    routines.

But, I don't know what we could write into the specification to make this
happen.  It seems that we really just need smart implementers.

--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide