Subject: Re: [bitcoindev] Re: Great Consensus Cleanup Revival

From: Mark F <[email-masked]>
Date: Wed, 17 Apr 2024 17:46:23 -0700 (PDT)

On Wednesday, March 27, 2024 at 4:00:34 AM UTC-7 Antoine Poinsot wrote:

The only beneficial case I can remember about the timewarp issue is 
"forwarding blocks" by maaku for on-chain scaling:
http://freico.in/forward-blocks-scalingbitcoin-paper.pdf

I would not qualify this hack of "beneficial". Besides the centralization 
pressure of an increased block frequency, leveraging the timewarp to 
achieve it would put the network constantly on the Brink of being seriously 
(fatally?) harmed. And this sets pernicious incentives too. Every 
individual user has a short-term incentive to get lower fees by the 
increased block space, at the expense of all users longer term. And every 
individual miner has an incentive to get more block reward at the expense 
of future miners. (And of course bigger miners benefit from an increased 
block frequency.)

Every single concern mentioned here is addressed prominently in the 
paper/presentation for Forward Blocks:

* Increased block frequency is only on the compatibility chain, where the 
content of blocks is deterministic anyway. There is no centralization 
pressure from the frequency of blocks on the compatibility chain, as the 
content of the blocks is not miner-editable in economically meaningful 
ways. Only the block frequency of the forward block chain matters, and here 
the block frequency is actually *reduced*, thereby decreasing 
centralization pressure.

* The elastic block size adjustment mechanism proposed in the paper is 
purposefully constructed so that users or miners wanting to increase the 
block size beyond what is currently provided for will have to pay 
significantly (multiple orders of magnitude) more than they could possibly 
acquire from larger blocks, and the block size would re-adjust downward 
shortly after the cessation of that artificial fee pressure.

* Increased block frequency of compatibility blocks has no effect on the 
total issuance, so miners are not rewarded by faster blocks.

You are free to criticize Forward Blocks, but please do so by actually 
addressing the content of the proposal. Let's please hold a standard of 
intellectual excellence on this mailing list in which ideas are debated 
based on content-level arguments rather than repeating inaccurate takes 
from Reddit/Twitter.

To the topic of the thread, disabling time-warp will close off an unlikely 
and difficult to pull off subsidy draining attack that to activate would 
necessarily require weeks of forewarning and could be easily countered in 
other ways, with the tradeoff of removing the only known mechanism for 
upgrading the bitcoin protocol to larger effective block sizes while 
staying 100% compatible with un-upgraded nodes (all nodes see all 
transactions).

I think we should keep our options open.

-Mark

-- 
You received this message because you are subscribed to the Google Groups "Bitcoin Development Mailing List" group.
To unsubscribe from this group and stop receiving emails from it, send an email to [email-masked].
To view this discussion on the web visit https://groups.google.com/d/msgid/bitcoindev/62640263-077c-4ac7-98a6-d9c17913fca0n%40googlegroups.com.