Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id B26895AC for ; Thu, 11 May 2017 18:17:21 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-vk0-f45.google.com (mail-vk0-f45.google.com [209.85.213.45]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 3C911F0 for ; Thu, 11 May 2017 18:17:21 +0000 (UTC) Received: by mail-vk0-f45.google.com with SMTP id x71so6051523vkd.0 for ; Thu, 11 May 2017 11:17:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to; bh=Q//+hKdIpccbnAks7zlbQnFRtd1KucLkQ1mhjB8vFNc=; b=rhGS43lGX4EfLNbECQZVNFgcyT8R7EVxvjhnDMRjtvzPJGCnj+xK5x5J3H/Ebwz5qY uUrY5jDvUiDZfM0juuppORXeuugZMVheFQAGmKT7ynv1+QFKrzamKU/3QPfBLDbIw3nt W48w6cnUg5AjWo2nr6r+pKw6yqmUzbIOe0qnTF15prirTjj5QuXo4t4byGO3TYjfX6fV tmRw4YsAHJyn05sPddu8Wq0mHwYzExJ/fx1NREkAN9YiJFpCuxY58MAwx4Os7osznUby fL3Tpo88imbI0yw2/9CimQNEWj6PM1UfkZXpAnKtyivHlkaDq3hZbt9y89EKAbBo3qTy PbzQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to; bh=Q//+hKdIpccbnAks7zlbQnFRtd1KucLkQ1mhjB8vFNc=; b=n+4mpULZtrDotzYAbaw1H9qN0eW5hK0CFZc32tKUtjA3Ka57RgpOqjvHA0GoYioII+ lE9AhIKyNghNf+F42JK5PwpcyBsIH0xyirfp5rEJbSERILaDNggESCh/vv0v/eB1lYjS CwfNbpedkR7BxGAARs0GAE/7Eg62pQHL6ozSjDCAaG+GOClZxBZFEopDdzEU7BSBL45g usUQA0GPL+QKrMFA8SBcQhMpQpTkym9F94ALjIQixvDkCxSvQ6p8cKChktHXybcQE/BV i+49iwDCqx6l99Y3JzwZklt7mnwP6vKu5Q2TqBm5F5bKtSvodBK72IenCUFYBawu/fEO zrLA== X-Gm-Message-State: AODbwcDH9HaadspWGOaGJiLRQQiGGqAhi1kTDZnekgmfqZmohFxTJtDz vKx6cd8UlP33spn9Ur1ZL49OpQt1Jvo4 X-Received: by 10.31.30.18 with SMTP id e18mr130184vke.52.1494526640094; Thu, 11 May 2017 11:17:20 -0700 (PDT) MIME-Version: 1.0 Sender: gmaxwell@gmail.com Received: by 10.103.20.66 with HTTP; Thu, 11 May 2017 11:17:19 -0700 (PDT) In-Reply-To: References: From: Gregory Maxwell Date: Thu, 11 May 2017 18:17:19 +0000 X-Google-Sender-Auth: pTjsPinKwUcNt_JBQaz2i19T-Xo Message-ID: To: Bitcoin Dev Content-Type: text/plain; charset=UTF-8 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE 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] BIP proposal: NODE_NETWORK_LIMITED service bits 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: Thu, 11 May 2017 18:17:22 -0000 It probably should be stated in terms of what you're promising to do-- 288 and 1152 blocks, not what we hope it will accomplish. Then advise clients to use peers with headroom because their estimates could be wrong and reorgs. Reorgs aren't the only concerns that drive larger numbers: The peak at syncing is at ~24 hours, but sometimes there are quite a few more than 144 blocks in 24 hours. Also, new blocks show up in the chain: you think you're 144 behind but by the time you connect you find you're 146 behind from that peer's perspective. I think it's a bit ambiguous what it's saying about the headers, especially because it goes into detail about address relay. I believe nodes with any of these settings should be willing to serve headers for their entire best chain. Perhaps you could say that this is equivalent to NODE_NETWORK except that they aren't necessarily willing to server historical blocks. I'm unsure about the third depth level. Perhaps that should be left undefined for sending right now and treated as least 1152 blocks by receivers-- I don't have any reason to think 7056 is a particularly useful choice, and we'll need another (longer) level for UTXO based sync. You could probably go further and say that nodes shouldn't send it now, but if sent it means they intend to keep 2016*2 blocks. (Not sending because the requirement for sending it may be that the node is able to send you a UTXO data feed.) > consider to switch a low percentage That isn't grammatical, you want "switching". But I think it would be better to say that when a node believe it is in sync enough to use NODE_NETWORK_LIMITED_X it should just treat them identically to NODE_NETWORK in peer selection. We don't really need any more topology distortion than that. In particular, I don't want to be in a case where NODE_NETWORK peers suddenly find themselves far less well connected. In terms of making room, a node network peer could choose to disconnect the least useful peers that aren't syncing from them to make more room for ones that are. This lets them decide what connections they want, based on how full they are and what is useful to them, rather than finding themselves all lonely because nodes decided to avoid them to be "helpful", and we already use disconnections to manage fullness. On Thu, May 11, 2017 at 3:13 PM, Jonas Schnelli via bitcoin-dev wrote: > Hi > > Currently, pruned peers have no way how to signal their (valuable) service. > A BIP proposal to improve this (draft): > https://github.com/jonasschnelli/bips/wiki/NODE_NETWORK_LIMITED-BIP-DRAFT > > Feedback is highly welcome. > > > > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >