Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id C2CCF1B78 for ; Wed, 9 Sep 2015 07:55:45 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-yk0-f182.google.com (mail-yk0-f182.google.com [209.85.160.182]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 2E084126 for ; Wed, 9 Sep 2015 07:55:44 +0000 (UTC) Received: by ykei199 with SMTP id i199so3020920yke.0 for ; Wed, 09 Sep 2015 00:55:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :content-type; bh=5j+llf8JtgJQBMq6RFedJe4vxyZuxoOd+yp/xvhWoNw=; b=MuSQcEgYO74vcIFh8x+/GxHyHz4hmrgfaeTo6Oez1eMMG5Pb3UZts3aqHMnop9vi78 Om9H1Jdhvq801AXWrVS/tKquL0hBh7j2/foe0k3Zw8cOZGTmuEpTXJgkeVCJqhg+RkNi kjBrKQHt1vdaDpzX2vDFq+GLDZXsCS0XfaMMOrYhae3HQ7qZNDik09xBMy/huPnrL3+v ym6DT8au5cYaLkgtuIH9zXsQafoIEUNqd6XzeAxXnolzMyO173HZf9QbTVSFj+7PU4Rc Ye2b2qXjn+vXFNXQUUosvSVPiTTt3GhHbU/Z9vEUFFIXWtvkg58FsBAluyK9RoeF3qFw b8mg== X-Gm-Message-State: ALoCoQk0CP14Hpbqd2KJUE4hiRrsQu8DrVJ/LKBriodbFAPzuMGmXgtwYsBFwDdm7RMtnZuiumIl MIME-Version: 1.0 X-Received: by 10.170.69.66 with SMTP id l63mr35950278ykl.89.1441785344131; Wed, 09 Sep 2015 00:55:44 -0700 (PDT) Received: by 10.13.205.6 with HTTP; Wed, 9 Sep 2015 00:55:44 -0700 (PDT) Date: Wed, 9 Sep 2015 09:55:44 +0200 Message-ID: From: Marcel Jamin To: Bitcoin Dev Content-Type: multipart/alternative; boundary=001a113998ba47b510051f4bcf48 X-Spam-Status: No, score=-0.7 required=5.0 tests=BAYES_20,HTML_MESSAGE, 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 Subject: [bitcoin-dev] Yet another blocklimit proposal / compromise X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Sep 2015 18:25:02 -0000 --001a113998ba47b510051f4bcf48 Content-Type: text/plain; charset=UTF-8 I propose to: a) assess what blocklimit is currently technically possible without driving up costs of running a node up too much. Most systems currently running a fullnode probably have some capacity left. b) set the determined blocklimit at the next reward halving c) then double the blocksize limit at every halving thereafter up to a hardlimit of 8GB. Reasoning: Doubling every four years will stay within expected technological growth. Cisco's VNI forecast predicts a 2.1-fold increase in global average fixed broadand speed from 2014 to 2019. Nielsen's law, which looks more at the power user (probably more fitting) is even more optimistic with +50% per year. This proposal can be considered a compromise between Pieter's and Gavin's proposals. While the growth rate is more or less what Pieter proposes, it includes an initial increase to kickstart the growth. If we start with 8MB, which seems to be popular among miners, we would reach 8GB in 2056 (as opposed to 2036 in BIP101). The start date (ca. mid 2016) is also a compromise between Pieter's 01/2017 and Gavin's 01/2016. It's simple, predictable and IMHO elegant -- block subsidy halves, blocksize limit doubles. It might make sense to update the limit more often in between, though. Either completely linearly based on a block's timestamp like in BIP101, or for example for each difficulty period. --001a113998ba47b510051f4bcf48 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I propose to:

a) assess what blocklimit= is currently technically possible without driving up costs of running a no= de up too much. Most systems currently running a fullnode probably have som= e capacity left.

b) set the determined blocklimit = at the next reward halving

c) then double the bloc= ksize limit at every halving thereafter up to a hardlimit of 8GB.

Reasoning:

Doubling= every four years will stay within expected technological growth. Cisco'= ;s VNI forecast predicts a 2.1-fold increase in global average fixed broada= nd speed from 2014 to 2019. Nielsen's law, which looks more at the powe= r user (probably more fitting) is even more optimistic with +50% per year.<= /div>

This proposal can be considered a compromise betwe= en Pieter's and Gavin's proposals. While the growth rate is more or= less what Pieter proposes, it includes an initial increase to kickstart th= e growth. If we start with 8MB, which seems to be popular among miners, we = would reach 8GB in 2056 (as opposed to 2036 in BIP101). The start date (ca.= mid 2016) is also a compromise between Pieter's 01/2017 and Gavin'= s 01/2016.

It's simple, predictable a= nd IMHO elegant -- block subsidy halves, blocksize limit doubles.

It might make sense to update the limit more often in betwe= en, though. Either completely linearly based on a block's timestamp lik= e in BIP101, or for example for each difficulty period.
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