From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 1D616B09 for ; Sat, 13 Apr 2019 19:09:33 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail148101.authsmtp.com (outmail148101.authsmtp.com [62.13.148.101]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 6CE076C5 for ; Sat, 13 Apr 2019 19:09:32 +0000 (UTC) Received: from mail-c237.authsmtp.com (mail-c237.authsmtp.com [62.13.128.237]) by punt16.authsmtp.com. (8.15.2/8.15.2) with ESMTP id x3DJ9TGw066630; Sat, 13 Apr 2019 20:09:29 +0100 (BST) (envelope-from user@petertodd.org) Received: from petertodd.org (ec2-52-5-185-120.compute-1.amazonaws.com [52.5.185.120]) (authenticated bits=0) by mail.authsmtp.com (8.15.2/8.15.2) with ESMTPSA id x3DJ9RMB073703 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sat, 13 Apr 2019 20:09:28 +0100 (BST) (envelope-from user@petertodd.org) Received: from [127.0.0.1] (localhost [127.0.0.1]) by petertodd.org (Postfix) with ESMTPSA id D48FE401EF; Sat, 13 Apr 2019 19:09:26 +0000 (UTC) Received: by localhost (Postfix, from userid 1000) id B33D122282; Sat, 13 Apr 2019 15:09:25 -0400 (EDT) Date: Sat, 13 Apr 2019 15:09:25 -0400 From: Peter Todd To: Dave Scotese , Bitcoin Protocol Discussion Message-ID: <20190413190925.peux7djbopy5xu3t@petertodd.org> References: <816FFA03-B4D9-4ECE-AF15-85ACBFA4BA8F@jonasschnelli.ch> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="lgrhmog5d2dszyhv" Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Server-Quench: a961d8a7-5e1f-11e9-960e-8434971169dc X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZIVwkA IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aQdMdwEUGUUGAgsB Am8bWVReUFR7W2o7 bghPaBtcak9QXgdq T0pMXVMcXAYcexVj e2weVRp1dwYIcX1w bAgzV3ZaCEwrclt4 F08CCGwHMG59YWYf BV1QcwBQeQRLfxlM PgMxNiYHcQ5VPz4z GA41ejw8IwAXIT9O XwQAME4CRg4CGDJ0 eiwyOn00G0QdXCU0 MwdO X-Authentic-SMTP: 61633532353630.1024:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 52.5.185.120/25 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Sun, 14 Apr 2019 12:58:51 +0000 Subject: Re: [bitcoin-dev] assumeutxo and UTXO snapshots X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 13 Apr 2019 19:09:33 -0000 --lgrhmog5d2dszyhv Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Apr 03, 2019 at 02:39:32PM -0700, Dave Scotese via bitcoin-dev wrot= e: > Every block's hash is smaller than the difficulty at that time. Block > 569927's hash was VERY small (started with 21 zeros). The ratio of block > hash to difficulty requirement (0xffffffff - difficulty, I think) could be > used to identify blocks as "special," thus providing the opportunity to > popularize unimportant but memorable-and-therefore-useful details. How c= an > they be useful if they are unimportant? They are useful for sanity > checking. For example, if the drunken bishop walk (or some other popular > randomart) produced by block 569927's hash looked like a face, that would > be memorable: "The block with the smallest hash in 2019 (maybe ever?) loo= ks > like a face after the drunken bishop walk." As hashest smaller than the target have no significance to the Bitcoin consensus I'd suggest not basing any features on that property. It's just as arbitrary as picking whole decimal number block heights, yet has the additi= onal downsides of being harder to compute, and being likely to confuse people as= to how the Bitcoin consensus works. --=20 https://petertodd.org 'peter'[:-1]@petertodd.org --lgrhmog5d2dszyhv Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEFcyURjhyM68BBPYTJIFAPaXwkfsFAlyyM+AACgkQJIFAPaXw kfusDgf+JS+zj8pRV0Nd5ryPQqisQdTGZn7RXrza/Fp+AH9yhxya62n5uvMc3Bgf U3tnwGNjeJu+wexk0fQN8RVA7Yp4tvqpTVtGxxCjtY7h/RQ9piQObaQlP0YYv8pk Lm7E6hM6hResz/LM2GDD/2mKL7iLQyPS9QkXJdk4sQSiR4H1EiQXeOqD34cqluLP qWo5eNAuG4dWriKtAPxfly0MfPo9PISCjmhz6AVV3whdryQ2hQV11p/dBMloDJ+0 APovks3qqQczc6/rgJURNRWnSP38Wp6z/pqBeH5iYObdFRa3heCYSZC99l/iuSNj qxVPViLJ03kspZegnvkiNTVCxu4sdA== =NKki -----END PGP SIGNATURE----- --lgrhmog5d2dszyhv--