Mark, It took you 3 minutes to respond to my e-mail. And I responded to you 4 minutes later. If you had responded to me in 10 minutes, I would be of out the office and we wouldn't have this dialogue. So 5 minutes is a lot of time. Obviously this is not a technical response to the technical issues you argue. But "minutes" is a time scale we humans use to measure time very often. :) On Fri, Aug 7, 2015 at 6:27 PM, Mark Friedenbach wrote: > Because halving the block interval comes with costs to SPV proofs (which > double the number of headers) and mining centralization (doubles the > selfish mining effect of latency) for the questionable benefit of a block > expectation time that is still measured in minutes, not seconds. > > Doubling the block size is safer than halving the block interval, for the > same effect in aggregate transactions per second. > > On Fri, Aug 7, 2015 at 2:18 PM, Sergio Demian Lerner via bitcoin-dev < > bitcoin-dev@lists.linuxfoundation.org> wrote: > >> What would you do? >> >> a. Double the block size >> b. Reduce the block rate to a half (average 5 minute blocks) >> >> Suppose this is a one time hard fork. There no drastic technical problems >> with any of them: "SPV" mining and the relay network has shown that block >> propagation is not an issue for such as small change. Mining centralization >> won't radically change for a 2x adjustment. >> >> So what would be best for Bitcoin? >> >> I suspect some (if not most of you) would choose b. Because reducing the >> block interval saves us real time. Waiting 30 minutes for a 3-block >> confirmation is... such a long time! Time that we value. Time that >> sometimes we waste waiting. Time that makes a difference for us. Doubling >> the block size does not change the user perception of Bitcoin in any way. >> >> Then why most discussions go around doubling the block size? >> >> Each change require less than 20 lines of code (*) in the reference code, >> and minimum change in other wallets. >> >> Currently there is no idle mining hardware for hire, so the security of >> six 10-minute block confirmation is equivalent to the security of six >> 5-minute block confirmations, as described in Satoshi's paper (if there >> were 51% spare mining hardware for hire, then obviously hiring that >> hardware for 30 minutes would cost less than hiring it for 1 hour). >> >> Why we discuss a 2x block size increase and not a 1/2 block interval >> reduction? Aren't we Bitcoin users after all? >> >> Best regards, >> Sergio. >> >> (*) b requires increasing the transaction version number, to support the >> old nLockTime rate. >> >> >> >> _______________________________________________ >> bitcoin-dev mailing list >> bitcoin-dev@lists.linuxfoundation.org >> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >> >