Subject: Re: [bitcoin-dev] Reorgs on SigNet - Looking for feedback on approach and parameters

From: Michael Folkson <[email-masked]>
Date: Fri, 10 Sep 2021 14:05:40 +0100

> I see zero reason whatsoever to not simply reorg ~every block, or as often as is practical. If users opt in to wanting to test with reorgs, they should be able to test with reorgs, not wait a day to test with reorgs.

One of the goals of the default Signet was to make the default Signet
resemble mainnet as much as possible. (You can do whatever you want on
a custom signet you set up yourself including manufacturing a re-org
every block if you wish.) Hence I'm a bit wary of making the behavior
on the default Signet deviate significantly from what you might
experience on mainnet. Given re-orgs don't occur that often on mainnet
I can see the argument for making them more regular (every 8 hours
seems reasonable to me) on the default Signet but every block seems
excessive. It makes the default Signet into an environment for purely
testing whether your application can withstand various flavors of edge
case re-orgs. You may want to test whether your application can
withstand normal mainnet behavior (no re-orgs for long periods of
time) first before you concern yourself with re-orgs.

> Why bother with a version bit? This seems substantially more complicated than the original proposal that surfaced many times before signet launched to just have a different reorg signing key. Thus, users who wish to follow reorgs can use a 1-of-2 (or higher multisig) and users who wish to not follow reorgs would use a 1-of-1 (or higher multisig), simply marking the reorg blocks as invalid without touching any header bits that non-full clients will ever see.

If I understand this correctly this is introducing a need for users to
sign blocks when currently with the default Signet the user does not
need to concern themselves with signing blocks. That is entirely left
to the network block signers of the default Signet (who were AJ and
Kalle last time I checked). Again I don't think this additional
complexity is needed on the default Signet when you can set up your
own custom Signet if you want to test edge case scenarios that deviate
significantly from what you are likely to experience on mainnet. A
flag set via a configuration argument (the AJ, 0xB10C proposal) with
no-reorgs (or 8 hour re-orgs) as the default seems to me like it would
introduce no additional complexity to the casual (or alpha stage)
tester experience though of course it introduces implementation
complexity.

To move the default Signet in the direction of resembling mainnet even
closer would be to randomly generate batches of transactions to fill
up blocks and create a fee market. It would be great to be able to
test features like RBF and Lightning unhappy paths (justice
transactions, perhaps even pinning attacks etc) on the default Signet
in future.

-- 
Michael Folkson
Email: [email-masked]
Keybase: michaelfolkson
PGP: 43ED C999 9F85 1D40 EAF4 9835 92D6 0159 214C FEE3