Re: [quicwg/base-drafts] create codec streams only when necessary (#2090)

MikkelFJ <notifications@github.com> Wed, 12 December 2018 10:12 UTC

Return-Path: <bounces+848413-a050-quic-issues=ietf.org@sgmail.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 683D312777C for <quic-issues@ietfa.amsl.com>; Wed, 12 Dec 2018 02:12:41 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.056
X-Spam-Level:
X-Spam-Status: No, score=-3.056 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_IMAGE_ONLY_28=1.404, HTML_MESSAGE=0.001, MAILING_LIST_MULTI=-1, RCVD_IN_DNSWL_NONE=-0.0001, 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 u7bgkQWU76Ow for <quic-issues@ietfa.amsl.com>; Wed, 12 Dec 2018 02:12:38 -0800 (PST)
Received: from o4.sgmail.github.com (o4.sgmail.github.com [192.254.112.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 90794131188 for <quic-issues@ietf.org>; Wed, 12 Dec 2018 02:12:38 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=github.com; h=from:reply-to:to:cc:in-reply-to:references:subject:mime-version:content-type:content-transfer-encoding:list-id:list-archive:list-post:list-unsubscribe; s=s20150108; bh=jmhFqKh1JVuWPRVYKiGdzOKRIJo=; b=iNdz8H8SspNYVjmJ TVXBwIvpTvQLek3Rym2HVRWM4RyErZOjCkdNjYzmasP86FFv9ChYALnB9CeheMMs WC2IMeRTwwrOpCfCCzGi/Zqq/hMYdZPrSM+oMgH/2xRJ2IgmCmQNvLWf8yeiZDYH EEdmI07zKy/IhlPulo3rgdjh/OM=
Received: by filter0106p1iad2.sendgrid.net with SMTP id filter0106p1iad2-2379-5C10DF14-21 2018-12-12 10:12:36.743663869 +0000 UTC m=+125008.515466984
Received: from github-lowworker-5909e27.cp1-iad.github.net (unknown [192.30.252.35]) by ismtpd0037p1iad2.sendgrid.net (SG) with ESMTP id vm6KgQe3Sp62yJ9iYALOLA for <quic-issues@ietf.org>; Wed, 12 Dec 2018 10:12:36.777 +0000 (UTC)
Received: from github.com (localhost [127.0.0.1]) by github-lowworker-5909e27.cp1-iad.github.net (Postfix) with ESMTP id BA74C3E0958 for <quic-issues@ietf.org>; Wed, 12 Dec 2018 02:12:36 -0800 (PST)
Date: Wed, 12 Dec 2018 10:12:36 +0000
From: MikkelFJ <notifications@github.com>
Reply-To: quicwg/base-drafts <reply+0166e4ab1fce50b25a123a27244bca74d21ae67c2253268392cf000000011828a11492a169ce170ba08e@reply.github.com>
To: quicwg/base-drafts <base-drafts@noreply.github.com>
Cc: Subscribed <subscribed@noreply.github.com>
Message-ID: <quicwg/base-drafts/pull/2090/c446533829@github.com>
In-Reply-To: <quicwg/base-drafts/pull/2090@github.com>
References: <quicwg/base-drafts/pull/2090@github.com>
Subject: Re: [quicwg/base-drafts] create codec streams only when necessary (#2090)
Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="--==_mimepart_5c10df14b8c11_55f93f827bcd45b41331f2"; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Precedence: list
X-GitHub-Sender: mikkelfj
X-GitHub-Recipient: quic-issues
X-GitHub-Reason: subscribed
X-Auto-Response-Suppress: All
X-GitHub-Recipient-Address: quic-issues@ietf.org
X-SG-EID: l64QuQ2uJCcEyUykJbxN122A6QRmEpucztpreh3Pak2wKXKcSns3Jt3ceEGQiv+LrXfNRS0wD7b3VT fc+h4nUJBqPgnuM30rs6eo9SrGw8FUFs8XGxmy+GrIstT+abWwsbRDO34XRF+sHkokx/nnHw6Kyn7R SQIh0uacBvYbpoSd+PzhzsoUOf5PD5Y5xBmNKq/ZawxyiTjRwDZAnGGUlA==
Archived-At: <https://mailarchive.ietf.org/arch/msg/quic-issues/XQZ2porWzz4eHvnED_6CutlIJzM>
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, 12 Dec 2018 10:12:42 -0000

I agree with MT that unnecessary concurrency is bad, but without digging into MT's architecture, I'd just point out that atomic reads or writes of integers are generally very cheap operations, unlike atomic exchange and the likes. This only applies when you can afford to react lazily to updates - such as more flow credits available. Technically you may need a costly bus sync (fence) to eventually see writes by other cores, but in praxis this happen soon enough.

-- 
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/pull/2090#issuecomment-446533829