Mining updates for 0.13.0

sdaftuar commented at 3:01 pm on June 30, 2016: member

There’s a few mining-related to-do’s that I thought we should track for the 0.13.0 release, so that we hopefully can avoid dealing with last-minute surprises.

Segwit’s merge has disabled the ancestor feerate mining algorithm by default, unless miners start using the new -blockmaxcost argument instead of -blockmaxsize or set -blockmaxsize > 3999000. This is because the size-accounting required by -blockmaxsize hasn’t been added to the package-selection code yet (which is optimized for fee per “block cost”, aka “virtual size”). I plan to address this in a PR shortly by adding the size-accounting to the package-selection code. [#8295]
I noticed that -blockminsize is not supported by the package selection code. This is something that of course could be added, but this seems like a feature that may not be relevant to anyone anymore. Can we just remove this command line argument? EDIT: from discussion on IRC, seems like the best path forward will be to get rid of the argument, but warn users if they try to set it. [#8295]
Should we remove the old transaction selection algorithm, addScoreTxs()? I believe that the new package selection algorithm is strictly superior to the old algorithm, but it is of course new code that has not received the battle-testing in production environments that the old algorithm has received. Nevertheless, if we don’t plan to add a way to enable the old algorithm, it seems to me like there’s little reason to leave the dead code lying around – we can always resurrect it from git history if we need to.
My suggestion would be to remove it, but if someone else is interested in adding support to enable it from the command line, that seems fine too. [#8295]
We need to update the release notes – description of the ancestor feerate mining algorithm and command line option changes (-blockmaxcost and its interaction with -blockmaxsize, and removal of -blockminsize if we choose to remove it). [#8374]
Improve the --help text for the -blockmaxcost option. Maybe we can cite the BIP where this is defined, perhaps combined with not translating the term “block cost” which is defined in the BIP? [#8363, #8359]

laanwj added this to the milestone 0.13.0 on Jun 30, 2016

laanwj added the label Mining on Jun 30, 2016

luke-jr commented at 4:02 pm on June 30, 2016: member

Why does CPFP depend on size/cost limits? I would think it would work just the same, simply with the block creation finishing at a different point?

sipa commented at 4:09 pm on June 30, 2016: member

@luke-jr Simply because ancestor accounting for vsize/cost is implemented, but not for bytes. It’s easy to fix, and if we want to, we should.

sdaftuar commented at 5:08 pm on June 30, 2016: member

I attempted to address the first 3 items in #8295.

If we do end up removing addScoreTxs() then we can also remove the “mining_score” index from the mempool’s multi_index, mapTx. Anyone have thoughts on that? Also it’s not clear to me whether anyone has a preference on removing code like this for 0.13, or after 0.13 is branched off (I don’t feel strongly either way).

ghost commented at 1:43 pm on July 21, 2016: none

Speaking of hard forks, wonder how /u/luke-jr is doing on the 2MB hard fork code that was promised to miners within the next 10 days. Greg Maxwell incredibly hasn’t the slightest idea about the progress of one of Blockstream’s contractors and his fellow developer. This was promised to miners many months ago. Can’t wait to see another empty promise broken.

Reddit Comment @luke-jr Is that correct or just rumor? Will 2 MB blocksize come in 13.0 update?

sipa commented at 1:50 pm on July 21, 2016: member

Anyone is free to make proposals about hard forks, and Bitcoin Core will adopt proposals that are uncontroversial to the community. There is no such proposal at this time, so Bitcoin Core 0.13 will certainly not include one.

This discussion should be held with a wider audience (for example, the next Scaling Bitcoin conference that was recently announced), but is off topic on the issue tracker for a single implementation.

sdaftuar commented at 4:19 pm on July 21, 2016: member

Closing now that all tasks have been completed.

sdaftuar closed this on Jul 21, 2016

MarcoFalke locked this on Sep 8, 2021

Mining updates for 0.13.0 #8294