Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1T24Qd-0006nK-Ju for bitcoin-development@lists.sourceforge.net; Thu, 16 Aug 2012 18:04:19 +0000 X-ACL-Warn: Received: from mail-qc0-f175.google.com ([209.85.216.175]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1T24Qc-0004fg-Ue for bitcoin-development@lists.sourceforge.net; Thu, 16 Aug 2012 18:04:19 +0000 Received: by qcad10 with SMTP id d10so2594684qca.34 for ; Thu, 16 Aug 2012 11:04:13 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:x-originating-ip:in-reply-to:references:date :message-id:subject:from:to:cc:content-type:x-gm-message-state; bh=KF6KzVIaBVVMR8aUPxav+4b65cOCx0ZisahOkVLwXUA=; b=R8gxmFaYcmbyWdWGwFB3870RPTZmQG38AyqizXQxfyb/jEyopkAWoSU4yekNNt1pW7 5XOpGTBoBapQ2+f5mMR/T9oiFCsQBqYgKfpqeomuNKPMyqoVW0MKyoui7LC1t19G/MPc Hkyg6IMhiSD/BV/eMqxTyp/kMaGn7Jh5p+S28TuRFL85Ej+DE0oA3qgSRpsLHZ2N1iFB 8rAgBYbr8piPsix7gEHkQtvlvo47vu1O5OeS59cmfjX/3xuieRXJ0tdDGLcMqwGmtwul JFIuyVki19fznB/aZm7z/9SQcokokOyTLbpmqXHTMwRaOGVjfLDcvPiDzX3NOm9wICTP CncQ== MIME-Version: 1.0 Received: by 10.229.135.149 with SMTP id n21mr1271091qct.131.1345140253339; Thu, 16 Aug 2012 11:04:13 -0700 (PDT) Received: by 10.49.97.6 with HTTP; Thu, 16 Aug 2012 11:04:13 -0700 (PDT) X-Originating-IP: [2001:4830:1603:2:21c:c0ff:fe79:c8c2] In-Reply-To: <20120816175637.GA13454@vps7135.xlshosting.net> References: <20120816175637.GA13454@vps7135.xlshosting.net> Date: Thu, 16 Aug 2012 14:04:13 -0400 Message-ID: From: Jeff Garzik To: Pieter Wuille Content-Type: text/plain; charset=ISO-8859-1 X-Gm-Message-State: ALoCoQn4BJ71PJc+QSHTsTkBnaguCDei7MdtYZjC3z5BQL1Gbg68L6bZ7t3Ca3cBnMfs1qir5R5h X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. X-Headers-End: 1T24Qc-0004fg-Ue Cc: Bitcoin Development Subject: Re: [Bitcoin-development] BIP 35: add mempool message 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: Thu, 16 Aug 2012 18:04:19 -0000 On Thu, Aug 16, 2012 at 1:56 PM, Pieter Wuille wrote: > I suppose it is interesting in general for nodes to > get a memory pool refill at startup anyway. Yes. >> An "inv" message is always returned, even if empty. > > I'm not sure about this last. What is it good for? inv packets can always be > sent, even not in response to others, so it is not that this gives you an > acknowledgement the mempool is updated? A simple guarantee of 1:1 correspondence between request and response. The bitcoin protocol sometimes simply elides a response when the response would be empty, and this makes it difficult to know whether a request is timing out or already processed. Sending a ping(nonce) after each P2P command is another way of achieving same :) > This seems safe, although it forces other full implementations that want to > expose protocol version 60002 (or later) to also implement this. What do they > think about this? > > I would like to suggest to allocate an extra service bit for this. We still > have 63 left, and this is a well-defined and useful extra service that was > not yet provided by any earlier node. Doing that would also mean that > mempool-providing survices may be discovered before connecting to them, as > the service bits are carried around in addr messages. Any opinions about that? An nServices bit would be a better fit for this optional service, but nServices bits seemed like a scarce resource, so I elected to be conservative. Absent the scarce-resource concern, I'd vote for an nServices bit. -- Jeff Garzik exMULTI, Inc. jgarzik@exmulti.com