Before bip94 there was an assumption that the minimum permitted
timestamp is GetMedianTimePast() + 1.
This commit splits a helper function out of UpdateTime() to
obtain the minimum time in a way that takes the
timewarp attack rule into account.
733fa0b0a1 miner: never create a template which exploits the timewarp bug (Antoine Poinsot)
Pull request description:
This check was introduced in #30681 but only enabled for testnet4. To avoid potentially creating an invalid block template if a soft fork to fix the timewarp attack were to activate in the future, we should have this check on all networks. It also seems wise for our miner to not support it whether or not a soft fork activates to fix it at the consensus level.
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Sjors:
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fjahr:
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TheCharlatan:
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Tree-SHA512: 9b3bc8b26a57f93425b17dda80bcfac4ecb750a3d26bc3eb8df619135634e369ac15982fac0c9770b1df207bd2e418ffe02a98f37968f024e55262d97715a4f5
- The package feerates are ordered by the sequence in which
packages are selected for inclusion in the block template.
- The commit also tests this new behaviour.
Co-authored-by: willcl-ark <will@256k1.dev>
Providing a script for the coinbase transaction is only done in test code
and for CPU solo mining.
Production miners use the getblocktemplate RPC which omits the coinbase
transaction entirely from its block template, leaving it to external (pool)
software to construct it.
A coinbase script can still be passed via BlockCreateOptions instead.
A temporary overload is added so that the test can be modified in the
next commit.
192dac1d33 [refactor] Cleanup BlockAssembler mempool usage (TheCharlatan)
Pull request description:
The `addPackageTxs` method of the `BlockAssembler` currently has access to two mempool variables, as an argument and as a member. Clean this up and clarify that they both are the same mempool instance by removing the argument and instead only using the member variable in the method.
This was noticed in this PR review: https://github.com/bitcoin/bitcoin/pull/25223#discussion_r898164322.
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Tree-SHA512: a5ae7d6d771fbb5b54f23624b4d3429acf07bbe38179a462a078c825d60c89a725ad4e13fe7067eebea7dfec63c56c8f39b5077b0d949d594f500affcc1272d1
The `addPackageTxs` method of the `BlockAssembler` currently has access
to two mempool variables, as an argument and as a member. Clean this up
and clarify that they both are the same mempool instance by removing the
argument and instead only using the member variable in the method.
Co-Authored-By: Anthony Towns <aj@erisian.com.au>
Co-authored-by: stickies-v <stickies-v@protonmail.com>
When generating a block template through e.g. getblocktemplate RPC,
we reserve 4000 weight units and 400 sigops. Pools use this space
for their coinbase outputs.
At least one pool patched their Bitcoin Core node to adjust
these hardcoded values. They eventually produced an invalid
block which exceeded the sigops limit.
https://bitcoin.stackexchange.com/questions/117837/how-many-sigops-are-in-the-invalid-block-783426
The existince of such patches suggests it may be useful to
make this value configurable. This commit would make such a
change easier.
The main motivation however is that the Stratum v2 spec
requires the pool to communicate the maximum bytes they intend
to add to the coinbase outputs. A proposed change to the spec
would also require them to communicate the maximum number of sigops.
This commit also documents what happens when
-blockmaxweight is lower than the coinbase
reserved value.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
Rather than pass options individually to createNewBlock and then
combining them into BlockAssembler::Options, this commit introduces
BlockCreateOptions and passes that instead.
Currently there's only one option (use_mempool) but the next
commit adds more.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
AddToBlock was called repeatedly from `addPackageTxs` where the constant value of `printpriority` is recalculated every time.
Since its behavior was changed in 400b151, I've named the variable accordingly.
This showed up during profiling of AssembleBlock, fetching it once in the constructor results in a measurable speed increase for many iterations.
> ./src/bench/bench_bitcoin --filter='AssembleBlock' --min-time=1000
before:
| ns/op | op/s | err% | total | benchmark
|--------------------:|--------------------:|--------:|----------:|:----------
| 155,558.97 | 6,428.43 | 0.1% | 1.10 | `AssembleBlock`
after:
| ns/op | op/s | err% | total | benchmark
|--------------------:|--------------------:|--------:|----------:|:----------
| 148,083.68 | 6,752.94 | 0.1% | 1.10 | `AssembleBlock`
Co-authored-by: furszy <mfurszy@protonmail.com>
This makes the options argument for BlockAssembler constructor mandatory,
dropping implicit use of ArgsManager. The caller i.e. the Mining
interface implementation now handles this.
In a future Stratum v2 change the Options object needs to be
mofified after arguments have been processed. Specifically
the pool communicates how many extra bytes it needs for
its own outputs (payouts, extra commitments, etc). This will need
to be substracted from what the user set as -blockmaxweight.
Such a change can be implemented in createNewBlock, after
ApplyArgsManOptions.