Well a reversed upgrade is an upgrade that went wrong ;) Anyway, the incident makes it even more important for people to upgrade, well except, perhaps, for miners...
Forks are caused by rejection criteria, hence: 1. If you introduce new rejection criteria in an upgrade miners should upgrade _first_. 2. If you loosen some rejection criteria miners should upgrade _last_. 3. If you keep the same criteria assume 2. /M On 12/03/2013, at 13:11, Mike Hearn <m...@plan99.net> wrote: > I'm not even sure I'd say the upgrade "went wrong". The problem if > anything is the upgrade didn't happen fast enough. If we had run out > of block space a few months from now, or if miners/merchants/exchanges > had upgraded faster, it'd have made more sense to just roll forward > and tolerate the loss of the older clients. > > This really reinforces the importance of keeping nodes up to date. > > On Tue, Mar 12, 2013 at 12:44 PM, 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 ------------------------------------------------------------------------------ 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
