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 48A5DFC9 for ; Sun, 28 Jan 2018 17:30:34 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from newmail.dtrt.org (li1228-87.members.linode.com [45.79.129.87]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 411D62F5 for ; Sun, 28 Jan 2018 17:30:33 +0000 (UTC) Received: from harding by newmail.dtrt.org with local (Exim 4.89) (envelope-from ) id 1efqml-0005nM-Oj; Sun, 28 Jan 2018 17:30:31 +0000 Date: Sun, 28 Jan 2018 12:29:48 -0500 From: "David A. Harding" To: Sjors Provoost , Bitcoin Protocol Discussion Message-ID: <20180128172948.5y32cc6rvf3saolj@fedora-23-dvm> References: <20180122200023.GA1055@savin.petertodd.org> <7yyS0mCgC8UWMYR_Jf1hB_GkkGj6Iu8tnIO7TeXWWyCrg9j4RZ7ziprCPZcv2xsFZdUzcFuHyeMU2-RBujzlSXdUAWlqdricuL2abaX0PWE=@protonmail.com> <20180124074453.GC12767@savin.petertodd.org> <36682FF4-5C68-4610-9E82-FCE6F93E050F@sprovoost.nl> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="sjj45u6qc2brbp46" Content-Disposition: inline In-Reply-To: <36682FF4-5C68-4610-9E82-FCE6F93E050F@sprovoost.nl> User-Agent: NeoMutt/20170113 (1.7.2) X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] Transaction Merging (bip125 relaxation) 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: Sun, 28 Jan 2018 17:30:34 -0000 --sjj45u6qc2brbp46 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Jan 28, 2018 at 05:43:34PM +0100, Sjors Provoost via bitcoin-dev wr= ote: > Peter Todd wrote: > > In fact I considered only requiring an increase in fee rate, based on t= he > > theory that if absolute fee went down, the transaction must be smaller = and thus > > miners could overall earn more from the additional transactions they co= uld fit > > into their block. But to do that properly requires considering whether = or not > > that's actually true in the particular state the mempool as a whole hap= pens to > > be in, so I ditched that idea early on for the much simpler criteria of= both a > > feerate and absolute fee increase. >=20 > Why would you need to consider the whole mempool?=20 Imagine a miner is only concerned with creating the next block and his mempool currently only has 750,000 vbytes in it. If two 250-vbyte transactions each paying a feerate of 100 nanobitcoins per vbyte (50k total) are replaced with one 325-vbyte transaction paying a feerate of 120 nBTC (39k total), the miner's potential income from mining the next block is reduced by 11k nBTC. Moving away from this easily worked example, the problem can still exist even if a miner has enough transactions to fill the next block. For replacement consideration only by increased feerate to be guaranteed more profitable, one has to assume the mempool contains an effectively continuous distribution of feerates. That may one day be true of the mempool (it would be good, because it helps keep block production regular sans subsidy) but it's often not the case these days. -Dave --sjj45u6qc2brbp46 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJabgiLAAoJENnbQalsImnTpvAP/29o+vvgWdO7zSCpTgBpMeym Y1kWehAoIxRXVWS6qcmELnQf7LmLYYq26T+97esA6kGJ05GMEaoTlpdDu3R6N7Su dZLyCQJaZcB2Ilre2vIKF2icMZt6t0ZvPiZoVMu4GXkpiQM+FwkGkQo14uFTR0ph sRHncGmYO/EQQDRIIErdgJKK1BcLshyrBNIEUqE4lJuNQeamhmFp3RPpRB9syTIY 8zSljw2MJcj7+2hVOq1sLlBcq0KgSNrITHFERGan9aAREe6XXxAyVONIuWRtfYv6 XOMR+Pj9gDJag+BApsFmWPZ2LDoMX8ksE4xvzECY2uToa9Wa4zwecMGPh7RzK+5S mjg2YeS7dbsHnt43KhLmHstEqs9rMXvF8o7w1M5dDqVmyMIoIbUrLDDwYTLbYKza /6e3fsSxF4uAYbRVodYgvGingHNy2fgqweXERXGGwE0adk0z/m14iyebLUXaukS2 EkEp2+QZMxr4rl+kyedCA+oEdHqeGUWaZxpR+0MrQ5Ynxgh28BrHbfhOKrd0j/4n R0XFW8SRuSEiH+6QKC6f7R1RZzlsA3cpegFWVyuPI0msmBxCdy8ZLSuhP+/9j0n4 SAJDOIAzu557UbV9EUONtgeDFSXb5a16186U8h2kH4j+ifnPV6rs99pKB3F+7iMt TppsRZNkBLKJHZwnc1To =W65t -----END PGP SIGNATURE----- --sjj45u6qc2brbp46--