From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UFnF3-0007PG-SD for bitcoin-development@lists.sourceforge.net; Wed, 13 Mar 2013 15:05:21 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.149.95 as permitted sender) client-ip=62.13.149.95; envelope-from=pete@petertodd.org; helo=outmail149095.authsmtp.com; Received: from outmail149095.authsmtp.com ([62.13.149.95]) by sog-mx-3.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1UFnEy-0006lO-Uv for bitcoin-development@lists.sourceforge.net; Wed, 13 Mar 2013 15:05:21 +0000 Received: from mail-c232.authsmtp.com (mail-c232.authsmtp.com [62.13.128.232]) by punt7.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id r2DF59uv038166; Wed, 13 Mar 2013 15:05:09 GMT Received: from savin (76-10-178-109.dsl.teksavvy.com [76.10.178.109]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id r2DF52E7063124 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Wed, 13 Mar 2013 15:05:04 GMT Date: Wed, 13 Mar 2013 11:05:01 -0400 From: Peter Todd To: Luke-Jr Message-ID: <20130313150501.GA14067@savin> References: <201303131256.30144.luke@dashjr.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="SLDf9lqlvOQaIe6s" Content-Disposition: inline In-Reply-To: <201303131256.30144.luke@dashjr.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: 6304159f-8bef-11e2-b10b-0025903375e2 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aAdMdwEUFVQGAgsB AmUbWlFeUFh7WWc7 bAxPbAVDY01GQQRq WVdMSlVNFUsqA2h3 AxxrVRl0dAREfDB4 Y0VjEHZYXEB7cE8r X0YGQDsbZGY1an1N UUAKagNUcgZDfhxG bVUqVj1vNG8XDQg5 AwQ0PjZ0MThBJSBS WgQAK04nCR5NTnhl DxEOEDw0dQAA X-Authentic-SMTP: 61633532353630.1019:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 76.10.178.109/587 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Score: -1.5 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1UFnEy-0006lO-Uv Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] 0.8.1 ideas X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Mar 2013 15:05:22 -0000 --SLDf9lqlvOQaIe6s Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Mar 13, 2013 at 12:56:29PM +0000, Luke-Jr wrote: > Here's a simple proposal to start discussion from... >=20 > BEFORE block 262144: > - Never make a block that, combined with the previous 4 blocks, results i= n=20 > over 4500 transaction modifications. > - Reject any block that includes more than 4500 transaction modifications= on=20 > its own (slight soft-fork) > - (these rules should make older clients safe under most circumstances) >=20 > FROM block 262144 to block 393216 (hard fork #1): > - Never make, and reject any block that includes more than 24391 transact= ion=20 > modifications on its own (this *should* be equivalent to 1 MB) > - (this rules can make older client backports safe unless a reorg is more= than=20 > 6 blocks deep) >=20 > FROM block 393216 onward (hard fork #2): > - Never make, and reject any block that includes more than 48781 transact= ion=20 > modifications on its own (this *should* be equivalent to 2 MB) > - Accept blocks up to 2 MB in data size If we're going to consider doing this, at minimum we need to also include a separate limit for how much the UTXO set can be grown by each block, calculated as the size of the scriptPubKey + constant metadata. (tx hash, index #, nValue, nVersion, nHeight should cover it) A P2SH transaction txout would measure 71bytes under that model. Given that we haven't even shown we can limit the creation of txouts that can not be spent economically caution would dictate setting the UTXO growth limit fairly low, say 1/4th of the block limit. --=20 'peter'[:-1]@petertodd.org --SLDf9lqlvOQaIe6s Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAEBAgAGBQJRQJWcAAoJEH+rEUJn5PoEFR8IAKRGbTNc20qBtP9xsKubmE1U owWiK/3GodoswvIGvVcOkr6MaaOVvYrW/jyGFdRdiEospEs8kbsRSvyxhBsiPjuO Fc7lSec7cRt/XZKgUuQWK8npTjSBfr6p5jmVl1HD26hnCWS/DYf1oEI1L9bleE6w A8nEakM4/jkBhVWwoczsqaSk+yJR87DjvmF6lixS/Y27Nqf2B9TDACA4xkGWz6Ai zd8jZKv25hGpwbuYz9lDGPxmVG5s5v/gscVW3VLys9wlCOARPjpaO1WRkMveMqKv golzhiWxiqS5VeRq1WgxdclW3DqcADLlvIldEGLStQD1wsfeFsBCyijfqnaBEtA= =Vrqh -----END PGP SIGNATURE----- --SLDf9lqlvOQaIe6s--