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 74968AAC for ; Wed, 24 Jun 2015 02:12:28 +0000 (UTC) X-Greylist: delayed 00:09:31 by SQLgrey-1.7.6 Received: from laozi.macaubase.com (z83l79.static.ctm.net [202.175.83.79]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id DF99F140 for ; Wed, 24 Jun 2015 02:12:27 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by laozi.macaubase.com (Postfix) with ESMTP id 6BFDA7C41EC for ; Wed, 24 Jun 2015 10:02:54 +0800 (HKT) X-Virus-Scanned: amavisd-new at macaubase.com Received: from laozi.macaubase.com ([127.0.0.1]) by localhost (laozi.macaubase.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id P9e0QIw36bmV for ; Wed, 24 Jun 2015 10:02:54 +0800 (HKT) Received: from dmac13-2.local (nz129l231.bb122100.ctm.net [122.100.129.231]) by laozi.macaubase.com (Postfix) with ESMTPSA id ED7E57C41EB for ; Wed, 24 Jun 2015 10:02:53 +0800 (HKT) Message-ID: <558A0FCB.2040908@ktorn.com> Date: Wed, 24 Jun 2015 10:02:51 +0800 From: Filipe Farinha User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: bitcoin-dev@lists.linuxfoundation.org Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit 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: [bitcoin-dev] Mempool size consensus + dynamic block size re-targetting 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, 24 Jun 2015 02:12:28 -0000 To my knowledge so far the main proposals regarding block size changes are either based on predictions, which traditionally we're not very good at, or a voting mechanism by a limited set of stakeholders (miners) whose interests may not be aligned with the rest of the community. Neither strategy takes into account the most important factor: real-time changes to the mempool. This is for a valid reason, there is currently no consensus on the size of the mempool. So my question is: has anyone considered the pros and cons of creating consensus around the current (approximate) mempool size? I propose that, at the expense of some transaction overhead (3 or 4 extra bytes?), each full-node that broadcasts a new transaction can add a mempool_size field that represents their current view of the mempool. As blocks are mined with this new data (which may or not be aggregated in the block header), all nodes can quickly reach consensus on the current average/median/etc mempool size, and agree on a suitable periodic blocksize "re-targetting" (similarly to mining difficulty). Since all full-nodes (not just miners) get to vote with their transactions the consensus is truly global, and we don't have to change blocksize blindly in anticipation of an unpredictable future. Would this not work, and if not, why? Filipe Farinha