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author | Luke Dashjr <luke@dashjr.org> | 2018-03-07 14:43:11 +0000 |
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committer | bitcoindev <bitcoindev@gnusha.org> | 2018-03-07 14:43:18 +0000 |
commit | c3329e6ce75eefd273169a2862393cbad7862a48 (patch) | |
tree | db10c042ac6a4f2a4c4678b4d649895e9f5acc2c | |
parent | 05845186f2831ab529cec2600381e060b7e237ee (diff) | |
download | pi-bitcoindev-c3329e6ce75eefd273169a2862393cbad7862a48.tar.gz pi-bitcoindev-c3329e6ce75eefd273169a2862393cbad7862a48.zip |
Re: [bitcoin-dev] BIP proposal: Reserved nversion bits in blockheader
-rw-r--r-- | 25/0551fe115c8e9fbcddb308dc25851c059fd427 | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/25/0551fe115c8e9fbcddb308dc25851c059fd427 b/25/0551fe115c8e9fbcddb308dc25851c059fd427 new file mode 100644 index 000000000..a1601ed8c --- /dev/null +++ b/25/0551fe115c8e9fbcddb308dc25851c059fd427 @@ -0,0 +1,203 @@ +Return-Path: <luke@dashjr.org> +Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org + [172.17.192.35]) + by mail.linuxfoundation.org (Postfix) with ESMTPS id 685E110A6 + for <bitcoin-dev@lists.linuxfoundation.org>; + Wed, 7 Mar 2018 14:43:18 +0000 (UTC) +X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 +Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21]) + by smtp1.linuxfoundation.org (Postfix) with ESMTP id 315275F3 + for <bitcoin-dev@lists.linuxfoundation.org>; + Wed, 7 Mar 2018 14:43:17 +0000 (UTC) +Received: from ishibashi.localnet (unknown [IPv6:2001:470:5:265::71]) + (Authenticated sender: luke-jr) + by zinan.dashjr.org (Postfix) with ESMTPSA id C47A038A0C5C; + Wed, 7 Mar 2018 14:43:14 +0000 (UTC) +X-Hashcash: 1:25:180307:btcdrak@gmail.com::Eu76AhF0k1Em=9+m:dhRD +X-Hashcash: 1:25:180307:bitcoin-dev@lists.linuxfoundation.org::LF9EqQZt9Uw6TE2b:gfiP +From: Luke Dashjr <luke@dashjr.org> +To: Btc Drak <btcdrak@gmail.com>, + Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org> +Date: Wed, 7 Mar 2018 14:43:11 +0000 +User-Agent: KMail/1.13.7 (Linux/4.15.1-gentoo; KDE/4.14.37; x86_64; ; ) +References: <CADJgMzv85-So7F1+nyDP_xA2GH5erodA21PM-uAJw8P6_ix6hA@mail.gmail.com> +In-Reply-To: <CADJgMzv85-So7F1+nyDP_xA2GH5erodA21PM-uAJw8P6_ix6hA@mail.gmail.com> +X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F +X-PGP-Key-ID: BD02942421F4889F +X-PGP-Keyserver: hkp://pgp.mit.edu +MIME-Version: 1.0 +Content-Type: Text/Plain; + charset="iso-8859-15" +Content-Transfer-Encoding: 7bit +Message-Id: <201803071443.13417.luke@dashjr.org> +X-Spam-Status: No, score=-0.2 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED, + T_RP_MATCHES_RCVD, URIBL_DBL_SPAM, + URIBL_RHS_DOB autolearn=no version=3.3.1 +X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on + smtp1.linux-foundation.org +Subject: Re: [bitcoin-dev] BIP proposal: Reserved nversion bits in + blockheader +X-BeenThere: bitcoin-dev@lists.linuxfoundation.org +X-Mailman-Version: 2.1.12 +Precedence: list +List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org> +List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> +List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> +List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> +List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> +List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> +X-List-Received-Date: Wed, 07 Mar 2018 14:43:18 -0000 + +Why are you posting this obsolete draft? You've already received review in +private, and been given useful suggestions. There's even a shared Google Doc +with the current draft: + + https://docs.google.com/document/d/1GedKia78NUAtylCzeRD3lMlLrpPVBFg9TV9LRqvStak/edit?usp=sharing + +Again: + +* This is no different from what Timo and Sergio proposed years ago, and as +such should be based on their work instead of outright not-invented-here +respecification. The current draft integrates their work while not trying to +steal credit for it (they are included as primary authors). + +* The specification should be complete, including updates for GBT and the +Stratum mining protocol. These are included in the current draft. + +Additionally, it is not appropriate to begin using a draft BIP on mainnet +before any discussion or consensus has been reached. Doing so seems quite +malicious, in fact. I hope DragonMint miners can still operate using the +*current* Bitcoin protocol. + +Luke + + +On Wednesday 07 March 2018 8:19:57 AM Btc Drak via bitcoin-dev wrote: +> Hi, +> +> The following proposal reduces the number of version-bits that can be used +> for parallel soft-fork signalling, reserving 16 bits for non-specific use. +> This would reduce the number of parallel soft-fork activations using +> versionbits to from 29 to 13 and prevent node software from emitting false +> warnings about unknown signalling bits under the versionbits signalling +> system (BIP8/9). I chose the upper bits of the nVersion, because looking at +> the versionbits implementation in the most widely deployed node software, +> it is easier to implement than say annexing the lower 2 bytes of the field. +> +> The scope of the BIP is deliberately limited to reserving bits for general +> use without specifying specific uses for each bit, although there have +> previously been various discussions of some use-cases of nVersion bits +> including version-rolling AsicBoost[1], and nonce rolling to reduce CPU +> load on mining controllers because ntime-rolling can only be done for short +> periods otherwise it could have negative side effects distorting time. +> However, specific use cases are not important for this BIP. +> +> I am reviving discussion on this topic now, specifically, because the new +> DragonMint miner uses version-rolling AsicBoost on mainnet[2]. It is +> important to bring up so node software can adapt the versionbits warning +> system to prevent false positives. This BIP has the added advantage that +> when a new use for bits is found, mining manufacturers can play in the +> designated area without causing disruption or inconvenience (as +> unfortuntely, the use of version-rolling will cause until BIP8/9 warning +> systems are adapted). I appologise for the inconvenience in advance, but +> this is the unfortunate result of restraints while negotiating to get the +> patent opened[3] and licensed defensively[4] in the first place. +> +> I believe there was a similar proposal[5] made some years ago, before the +> advent of BIP9. This proposal differs in that it's primary purpose is to +> remove bits from the versionbits soft-fork activation system and earmark 16 +> bits for general use without allocating fixed uses for each bit. The BIP +> cites a couple of usecases for good measure, but they are just +> informational examples, not part of a specification laid down. For this +> reason, there no is mention of the version-rolling Stratum extension[6] +> specifics within the BIP text other than a reference to the specification +> itself. +> +> Refs: +> +> [1] https://arxiv.org/pdf/1604.00575.pdf +> [2] +> https://halongmining.com/blog/2018/03/07/dragonmint-btc-miner-uses-version-> rolling-asicboost/ [3] +> https://www.asicboost.com/single-post/2018/03/01/opening-asicboost-for-defe +> nsive-use/ [4] https://blockchaindpl.org/ +> [5] https://github.com/BlockheaderNonce2/bitcoin/wiki +> [6] http://stratumprotocol.org/stratum-extensions +> +> <pre> +> BIP: ? +> Title: Reserved nversion bits in blockheader +> Author: BtcDrak <btcdrak@gmail.com> +> Comments-Summary: No comments yet. +> Comments-URI: https://github.com/bitcoin/bips/wiki/Comments:BIP-???? +> Status: Draft +> Type: Informational +> Created: 2018-03-01 +> License: BSD-3-Clause +> CC0-1.0 +> </pre> +> +> ==Abstract== +> +> This BIP reserves 16 bits of the block header nVersion field for +> general purpose use and removes their meaning for the purpose of +> version bits soft-fork signalling. +> +> ==Motivation== +> +> There are a variety of things that miners may desire to use some of +> the nVersion field bits for. However, due to their use to coordinate +> miner activated soft-forks, full node software will generate false +> warnings about unknown soft forks if those bits are used for non soft +> fork signalling purposes. By reserving bits from the nVersion field +> for general use, node software can be updated to ignore those bits and +> therefore will not emit false warnings. Reserving 16 bits for general +> use leaves enough for 13 parallel soft-forks using version bits. +> +> ==Example Uses== +> +> The following are example cases that would benefit from using some of +> the bits from the nVersion field. This list is not exhaustive. +> +> Bitcoin mining hardware currently can exhaust the 32 bit nonce field +> in less than 200ms requiring the controller to distribute new jobs +> very frequently to each mining chip consuming a lot of bandwidth and +> CPU time. This can be greatly reduced by rolling more bits. Rolling +> too many bits from nTime is not ideal because it may distort the +> timestamps over a longer period. +> +> Version-rolling AsicBoost requires two bits from the nVersion field to +> calculate 4-way collisions. Any two bits can be used and mining +> equipment can negotiate which bits are to be used with mining pools +> via the Stratum "version-rolling" extension. +> +> ==Specification== +> +> Sixteen bits from the block header nVersion field, starting from 13 +> and ending at 28 inclusive (0x1fffe000), are reserved for general use +> and removed from BIP8 and BIP9 specifications. A mask of 0xe0001fff +> should be applied to nVersion bits so bits 13-28 inclusive will be +> ignored for soft-fork signalling and unknown soft-fork warnings. +> +> This specification does not reserve specific bits for specific purposes. +> +> ==Backwards Compatibility== +> +> This proposal is backwards compatible, and does not require a soft +> fork to implement. +> +> ==References== +> +> [[bip-0008.mediawiki|BIP8]] +> [[bip-0009.mediawiki|BIP9]] +> [https://arxiv.org/pdf/1604.00575.pdf AsicBoost white paper] +> [https://github.com/BlockheaderNonce2/bitcoin/wiki nNonce2 proposal] +> [http://stratumprotocol.org/ Stratum protocol extension for +> version-rolling] +> +> ==Copyright== +> +> This document is dual licensed as BSD 3-clause, and Creative Commons +> CC0 1.0 Universal. + |