A related question...some people mentioned yesterday on #bitcoin-dev that 0.5 appeared to be compatible with 0.8. Was that only for the "fatal block" and would have forked 0.8 later too or is it something else? I'm having a hard time understanding this 0.5 thing, if someone can bring some light to it I would appreciate it.
Thanks in advance On 3/12/13, Pieter Wuille <pieter.wui...@gmail.com> wrote: > On Tue, Mar 12, 2013 at 11:13:09AM +0100, Michael Gronager wrote: >> Yes, 0.7 (yes 0.7!) was not sufficiently tested it had an undocumented and >> unknown criteria for block rejection, hence the upgrade went wrong. > > We're using "0.7" as a short moniker for all clients, but this was a > limitation that all > BDB-based bitcoins ever had. The bug is simply a limit in the number of lock > objects > that was reached. > > It's ironic that 0.8 was supposed to solve all problems we had due to BDB > (except the > wallet...), but now it seems it's still coming back to haunt us. I really > hated telling > miners to go back to 0.7, given all efforts to make 0.8 signficantly more > tolerable... > >> More space in the block is needed indeed, but the real problem you are >> describing is actually not missing space in the block, but proper handling >> of mem-pool transactions. They should be pruned on two criteria: >> >> 1. if they gets to old >24hr >> 2. if the client is running out of space, then the oldest should probably >> be pruned >> >> clients are anyway keeping, and re-relaying, their own transactions and >> hence it would mean only little, and only little for clients. Dropping >> free / old transaction is a much a better behavior than dying... Even a >> scheme where the client dropped all or random mempool txes would be a >> tolerable way of handling things (dropping all is similar to a restart, >> except for no user intervention). > > Right now, mempools are relatively small in memory usage, but with small > block sizes, > it indeed risks going up. In 0.8, conflicting (=double spending) > transactions in the > chain cause clearing the mempool of conflicts, so at least the mempool is > bounded by > the size of the UTXO subset being spent. Dropping transactions from the > memory pool > when they run out of space seems a correct solution. I'm less convinced > about a > deterministic time-based rule, as that creates a double spending incentive > at that > time, and a counter incentive to spam the network with your > risking-to-be-cleared > transaction as well. > > Regarding the block space, we've seen the pct% of one single block chain > space consumer > grow simultaneously with the introduction of larger blocks, so I'm not > actually convinced > there is right now a big need for larger blocks (note: right now). The > competition for > block chain space is mostly an issue for client software which doesn't deal > correctly > with non-confirming transactions, and misleading users. It's mostly a > usability problem > now, but increasing block sizes isn't guaranteed to fix that; it may just > make more > space for spam. > > However, the presence of this bug, and the fact that a full solution is > available (0.8), > probably helps achieving consensus fixing it (=a hardfork) is needed, and we > should take > advantage of that. But please, let's not rush things... > > -- > Piter > > ------------------------------------------------------------------------------ > Symantec Endpoint Protection 12 positioned as A LEADER in The Forrester > Wave(TM): Endpoint Security, Q1 2013 and "remains a good choice" in the > endpoint security space. For insight on selecting the right partner to > tackle endpoint security challenges, access the full report. > http://p.sf.net/sfu/symantec-dev2dev > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > -- Jorge Timón http://freico.in/ http://archive.ripple-project.org/ ------------------------------------------------------------------------------ Symantec Endpoint Protection 12 positioned as A LEADER in The Forrester Wave(TM): Endpoint Security, Q1 2013 and "remains a good choice" in the endpoint security space. For insight on selecting the right partner to tackle endpoint security challenges, access the full report. http://p.sf.net/sfu/symantec-dev2dev _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
