Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1RBRll-0008F1-UU for bitcoin-development@lists.sourceforge.net; Wed, 05 Oct 2011 13:44:21 +0000 X-ACL-Warn: Received: from backup-server.nordu.net ([193.10.252.66]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1RBRlh-0005RM-SD for bitcoin-development@lists.sourceforge.net; Wed, 05 Oct 2011 13:44:21 +0000 Received: from [192.168.0.8] (2508ds5-oebr.0.fullrate.dk [95.166.54.87]) (authenticated bits=0) by backup-server.nordu.net (8.14.3/8.14.3) with ESMTP id p95Di8lA005807 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Wed, 5 Oct 2011 15:44:09 +0200 (CEST) Mime-Version: 1.0 (Apple Message framework v1244.3) Content-Type: text/plain; charset=iso-8859-1 From: =?iso-8859-1?Q?Michael_Gr=F8nager?= In-Reply-To: Date: Wed, 5 Oct 2011 15:44:08 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <03BEA6AD-7EF2-41D0-91A3-D943A7B2964D@ceptacle.com> References: To: Gregory Maxwell X-Mailer: Apple Mail (2.1244.3) 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: 1RBRlh-0005RM-SD Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] vtxPrev 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: Wed, 05 Oct 2011 13:44:22 -0000 Oups - I was reading the code wrongly - going through = AddSupportingTransactions carefully again... The vtxPrev contains a list of the supporting confirmations up to 3 = confirmations back. So it is only of relevance (and only gets filled) if = you accept coins that are less than 3 confirmations old. In this case = you would like to resend the depending transactions to the network in = case of chain splits. This makes much more sense, but also, it is only of relevance when you = accept newly earned coins. And it will only be of relevance for half an = hour or so. Cheers, Michael On 05/10/2011, at 14:50, Gregory Maxwell wrote: > On Wed, Oct 5, 2011 at 8:31 AM, Michael Gr=F8nager = wrote: >> The vtxPrev stores 3 transactions back, but as transactions need 7 = block to maturity and respendability isn't it overkill - I mean it is = highly unlikely that a transaction gets invalid after 7 confirmations = and >=20 > They don't need 7 blocks to maturity and respendability. The software > will attempt to use older inputs when available but if not it will use > what it has. It's also prone to respending its own outputs quickly > because it reasonably trusts that it won't doublespend its own > transactions. >=20 > And, yes, if there is a deep split then its possible that inputs might > have been spent differently in the new split. But it's not especially > likely. Retransmitting one of your own txn's parents if its dropped > but not yet impossible sounds prudent to me. Michael Gronager, PhD Owner Ceptacle / NDGF Director, NORDUnet A/S Jens Juels Gade 33 2100 Copenhagen E Mobile: +45 31 62 14 01 E-mail: gronager@ceptacle.com