IETF Logo Mail Archive

Re: [quicwg/base-drafts] SetLossDetectionTime negative timeout (#2052)

Kazuho Oku <notifications@github.com> Wed, 28 November 2018 08:27 UTC

Return-Path: <noreply@github.com>
X-Original-To: quic-issues@ietfa.amsl.com
Delivered-To: quic-issues@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 4BE6D130E50 for <quic-issues@ietfa.amsl.com>; Wed, 28 Nov 2018 00:27:25 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.46
X-Spam-Level:
X-Spam-Status: No, score=-9.46 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.46, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=0.001, MAILING_LIST_MULTI=-1, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=github.com
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 7cCpLVTBwKCf for <quic-issues@ietfa.amsl.com>; Wed, 28 Nov 2018 00:27:23 -0800 (PST)
Received: from out-1.smtp.github.com (out-1.smtp.github.com [192.30.252.192]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 7D3A4130E4D for <quic-issues@ietf.org>; Wed, 28 Nov 2018 00:27:23 -0800 (PST)
Date: Wed, 28 Nov 2018 00:27:22 -0800
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=pf2014; t=1543393642; bh=7ZJkza7zmvDDMHDltXW5KpLCJdeF9Wb2aw2VCso4dns=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:List-ID: List-Archive:List-Post:List-Unsubscribe:From; b=gHiP67yvI2iR1kWCemwlmM2KevRAnB7ew2EtVINP3eEJo0wF/G3wEFEBflWNJmHIK mviyvYdSOIxlC4IotJr8rfwOp1xvBynvU2dOQCWiq0+su+3mirSYLJ+47U0cutz1Ge wqa7TxEs45f83L9Ma/FhJc6TuG43iIOIQITiXRzg=
From: Kazuho Oku <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+0166e4ab0adecb46406e48b98f0793ea4409e4b6c74d181792cf000000011816136a92a169ce16e756f7@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/issues/2052/442360989@github.com>
In-Reply-To: <quicwg/base-drafts/issues/2052@github.com>
References: <quicwg/base-drafts/issues/2052@github.com>
Subject: Re: [quicwg/base-drafts] SetLossDetectionTime negative timeout (#2052)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5bfe516a788bc_b883f912e2d45c01949ab"; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: kazuho
X-GitHub-Recipient: quic-issues
X-GitHub-Reason: subscribed
X-Auto-Response-Suppress: All
X-GitHub-Recipient-Address: quic-issues@ietf.org
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic-issues/t1MgfjVpdBbnw4S1hGu_ktbiXOM>
X-BeenThere: quic-issues@ietf.org
X-Mailman-Version: 2.1.29
List-Id: Notification list for GitHub issues related to the QUIC WG <quic-issues.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/quic-issues/>
List-Post: <mailto:quic-issues@ietf.org>
List-Help: <mailto:quic-issues-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/quic-issues>, <mailto:quic-issues-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 28 Nov 2018 08:27:26 -0000

@ianswett 
> To clarify, this is a case when alarms wake up late, since ideally if this was negative, the alarm should have executed, correct?

I could well be missing something, but my understanding that the case can happen with accurate alarms.

Consider the case when an endpoints view of packets are as follows:

|PN|sent_at|acked?|notes|
|---|---|---|---|
|1|0|Y|sent normally|
|2|100|N|sent normally|
|3|300|N|sent due to RTO|

At this point, the loss timer is set to 700 (i.e. 2 \* min_rto_timeout (200)).

Then, when the endpoint receives a packet containing an ACK for PN=2 at time 600, `rto_count` is reset to zero, because PN=2 is newly acked. Then, the loss timer becomes 500, which is 100 earlier than the current time.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/quicwg/base-drafts/issues/2052#issuecomment-442360989

v2.23.0 | Report a Bug | By Email