Re: [httpbis] #432: Review Cachability of Status Codes WRT "Negative Caching"
Mark Nottingham <mnot@mnot.net> Mon, 18 February 2013 00:13 UTC
Return-Path: <ietf-http-wg-request@listhub.w3.org>
X-Original-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Delivered-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id EA06821E805A for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sun, 17 Feb 2013 16:13:25 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.436
X-Spam-Level:
X-Spam-Status: No, score=-9.436 tagged_above=-999 required=5 tests=[AWL=1.163, BAYES_00=-2.599, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id IR20jBdw26ap for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sun, 17 Feb 2013 16:13:24 -0800 (PST)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id AB82A21E8055 for <httpbisa-archive-bis2Juki@lists.ietf.org>; Sun, 17 Feb 2013 16:13:24 -0800 (PST)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1U7ELX-0001oE-K8 for ietf-http-wg-dist@listhub.w3.org; Mon, 18 Feb 2013 00:12:39 +0000
Resent-Date: Mon, 18 Feb 2013 00:12:39 +0000
Resent-Message-Id: <E1U7ELX-0001oE-K8@frink.w3.org>
Received: from maggie.w3.org ([128.30.52.39]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <mnot@mnot.net>) id 1U7ELP-0001nQ-VR for ietf-http-wg@listhub.w3.org; Mon, 18 Feb 2013 00:12:31 +0000
Received: from mxout-08.mxes.net ([216.86.168.183]) by maggie.w3.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.72) (envelope-from <mnot@mnot.net>) id 1U7ELK-0007zm-8F for ietf-http-wg@w3.org; Mon, 18 Feb 2013 00:12:31 +0000
Received: from [192.168.1.80] (unknown [118.209.197.138]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by smtp.mxes.net (Postfix) with ESMTPSA id AAB64509B6 for <ietf-http-wg@w3.org>; Sun, 17 Feb 2013 19:12:04 -0500 (EST)
Content-Type: text/plain; charset="windows-1252"
Mime-Version: 1.0 (Mac OS X Mail 6.2 \(1499\))
From: Mark Nottingham <mnot@mnot.net>
In-Reply-To: <1B168529-9ECB-4A4D-9EC2-190447DB6B72@mnot.net>
Date: Mon, 18 Feb 2013 11:12:00 +1100
Content-Transfer-Encoding: quoted-printable
Message-Id: <2B8C0176-F957-4B69-B264-99CF556BD858@mnot.net>
References: <059.77033a1709a94099b974f5d7985e94b6@trac.tools.ietf.org> <1B168529-9ECB-4A4D-9EC2-190447DB6B72@mnot.net>
To: "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
X-Mailer: Apple Mail (2.1499)
Received-SPF: pass client-ip=216.86.168.183; envelope-from=mnot@mnot.net; helo=mxout-08.mxes.net
X-W3C-Hub-Spam-Status: No, score=-4.3
X-W3C-Hub-Spam-Report: AWL=-2.358, BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001
X-W3C-Scan-Sig: maggie.w3.org 1U7ELK-0007zm-8F bdc9be1484cf9717141dfd0d6f8aaaa8
X-Original-To: ietf-http-wg@w3.org
Subject: Re: [httpbis] #432: Review Cachability of Status Codes WRT "Negative Caching"
Archived-At: <http://www.w3.org/mid/2B8C0176-F957-4B69-B264-99CF556BD858@mnot.net>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/16638
X-Loop: ietf-http-wg@w3.org
Resent-Sender: ietf-http-wg-request@w3.org
Precedence: list
List-Id: <ietf-http-wg.w3.org>
List-Help: <http://www.w3.org/Mail/>
List-Post: <mailto:ietf-http-wg@w3.org>
List-Unsubscribe: <mailto:ietf-http-wg-request@w3.org?subject=unsubscribe>
I haven't seen any discussion, and this is our last ticket (at least for the moment). So, I'll make a proposal; we should identify the following additional status codes as cacheable (i.e., eligible for using a heuristic to determine freshness, in the absence of explicit information); • 204 (No Content) • 404 (Not Found) • 405 (Method Not Allowed) • 414 (Request URI Too Long) • 501 (Not Implemented) • 502 (Bad Gateway) • 503 (Service Unavailable) • 504 (Gateway Timeout) Note that I'm *not* proposing the following, even though they are negatively cached by some implementations, as I suspect doing so may cause interop problems: • 400 (Bad Request) • 403 (Forbidden) • 500 (Internal Server Error) Thoughts? On 11/02/2013, at 5:28 PM, Mark Nottingham <mnot@mnot.net> wrote: > ... and this is the ticked I just promised: > > Begin forwarded message: > >> From: "httpbis" <trac+httpbis@trac.tools.ietf.org> >> Subject: [httpbis] #432: Review Cachability of Status Codes WRT "Negative Caching" >> Date: 11 February 2013 5:27:44 PM AEDT >> To: mnot@pobox.com >> Reply-To: ietf-http-wg@w3.org >> >> #432: Review Cachability of Status Codes WRT "Negative Caching" >> ----------------------------+----------------------------- >> Reporter: mnot@pobox.com | Owner: >> Type: design | Status: new >> Priority: normal | Milestone: unassigned >> Component: p6-cache | Severity: In WG Last Call >> Keywords: | Origin: #223 >> ----------------------------+----------------------------- >> Currently, the following status codes are defined as cacheable -- that is, >> able to be stored without any explicit freshness information: >> >> - 200 (OK) >> - 203 (Non-Authoritative Information) >> - 206 (Partial Content) >> - 300 (Multiple Choices) >> - 301 (Moved Permanently) >> - 410 (Gone) >> >> However, many caches store other status codes (often called "Negative >> Caching") >> >> For example, both Squid and Traffic Server (which have considerable market >> share, and form the basis of many other implementations) negatively cache >> the following status codes: >> >> - 204 (No Content) >> - 400 (Bad Request) >> - 403 (Forbidden) >> - 404 (Not Found) >> - 405 (Method Not Allowed) >> - 414 (Request URI Too Long) >> - 500 (Internal Server Error) >> - 501 (Not Implemented) >> - 502 (Bad Gateway) >> - 503 (Service Unavailable) >> - 504 (Gateway Timeout) >> >> While some of these may be bad to cache by default (in particular, 400 and >> 500), others may make sense: for example, 204 seems straightforward, and >> 404 seems high-value. >> >> The major concern here is making semantic changes to the protocol. >> >> -- >> Ticket URL: <http://trac.tools.ietf.org/wg/httpbis/trac/ticket/432> >> httpbis <http://tools.ietf.org/wg/httpbis/> >> > > -- > Mark Nottingham http://www.mnot.net/ > > > > -- Mark Nottingham http://www.mnot.net/
- Fwd: [httpbis] #432: Review Cachability of Status… Mark Nottingham
- Re: [httpbis] #432: Review Cachability of Status … Mark Nottingham
- Re: [httpbis] #432: Review Cachability of Status … Amos Jeffries
- Re: [httpbis] #432: Review Cachability of Status … Mark Nottingham
- Re: [httpbis] #432: Review Cachability of Status … Mark Nottingham