e6fe1c37d0 rpc: Improve avoidpartialspends and avoid_reuse documentation (Fabian Jahr)
8f073076b1 wallet: Increase OUTPUT_GROUP_MAX_ENTRIES to 100 (Fabian Jahr)
Pull request description:
Follow-up to #17824.
This increases OUTPUT_GROUP_MAX_ENTRIES to 100 which means that OutputGroups will now be up to 100 outputs large, up from previously 10. The main motivation for this change is that during the PR review club on #17824 [several participants signaled](https://bitcoincore.reviews/17824.html#l-339) that 100 might be a better value here.
I think fees should be manageable for users but more importantly, users should know what they can expect when using the wallet with this configuration, so I also tried to clarify the documentation on `-avoidpartialspends` and `avoid_reuse` a bit. If there are other additional ways how or docs where users can be made aware of the potential consequences of using these parameters, please let me know. Another small upside is that [there seem to be a high number of batching transactions with 100 and 200 inputs](https://miro.medium.com/max/3628/1*sZ5eaBSbsJsHx-J9iztq2g.png)([source](https://medium.com/@hasufly/an-analysis-of-batching-in-bitcoin-9bdf81a394e0)) giving these transactions a bit of a larger anonymity set, although that is probably a very weak argument.
ACKs for top commit:
jnewbery:
ACK e6fe1c37d0
Xekyo:
retACK e6fe1c37d0
rajarshimaitra:
tACK `e6fe1c3`
achow101:
ACK e6fe1c37d0
glozow:
code review ACK e6fe1c37d0
Tree-SHA512: 79685c58bafa64ed8303b0ecd616fce50fc9a2b758aa79833e4ad9f15760e09ab60c007bc16ab4cbc4222e644cfd154f1fa494b0f3a5d86faede7af33a6f2826
51a3ac242c Have OutputGroup determine the value to use (Andrew Chow)
6d6d278475 Change SelectCoins_test to actually test SelectCoins (Andrew Chow)
9d3bd74ab4 Remove CreateTransaction while loop and some related variables (Andrew Chow)
6f0d5189af Remove use_bnb and bnb_used (Andrew Chow)
de26eb0e1f Do both BnB and Knapsack coin selection in SelectCoinsMinConf (Andrew Chow)
01dc8ebda5 Have KnapsackSolver actually use effective values (Andrew Chow)
bf26e018de Roll static tx fees into nValueToSelect instead of having it be separate (Andrew Chow)
cc3f14b27c Move output reductions for fee to after coin selection (Andrew Chow)
d97d25d950 Make cost_of_change part of CoinSelectionParams (Andrew Chow)
af5867c896 Move some calculations to common code in SelectCoinsMinConf (Andrew Chow)
1bf4a62cb6 scripted-diff: rename some variables (Andrew Chow)
Pull request description:
Changes `KnapsackSolver` to use effective values instead of just the nominal txout value. Since fees are taken into account during the selection itself, we finally get rid of the `CreateTransaction` loop as well as a few other things that only were only necessary because of that loop.
This should not change coin selection behavior at all (except maybe remove weird edge cases that were caused by the loop). In order to keep behavior the same, `KnapsackSolver` will select outputs with a negative effective value (as it did before).
ACKs for top commit:
ryanofsky:
Code review ACK 51a3ac242c. Looks good to go!
instagibbs:
review ACK 51a3ac242c
meshcollider:
re-light-utACK 51a3ac242c
Tree-SHA512: 372c27e00edcd5dbf85177421ba88f20bfdaf1791b6e3dc022c44876ecc379403e2375ed69e71c512c49e6af87641001ff385c4b25ab93684b3a08a53bf3824e
Instead of hijacking the effective_feerate to use the correct value
during coin selection, have OutputGroup be aware of whether we are
subtracting the fee from the outputs and provide the correct value to
use for selection.
To do this, OutputGroup now takes CoinSelectionParams and has a new
function GetSelectionAmount().
Remove the CreateTransaction while loop. Removes variables that were
only needed because of that loop. Also renames a few variables and
moves their declarations to where they are used.
Some subtractFeeFromOutputs handling is moved to after coin selection
in order to reduce their amounts once the fee is known.
If subtracting the fee reduces the change to dust, we will also now
remove the change output
Although the CreateTransaction loop currently remains, it should be
largely unused. KnapsackSolver will now account for transaction fees
when doing its selection.
In the previous commit, SelectCoinsMinConf was refactored to have some
calculations become shared for KnapsackSolver and SelectCoinsBnB. In
this commit, KnapsackSolver will now use the not_input_fees and
effective_feerate so that it include the fee for non-input things
(excluding a change output) so that the algorithm will select enough to
cover those fees. This is necessary for selecting on effective values.
Additionally, the OutputGroups
created for KnapsackSolver will actually have their effective values
calculated and set, and KnapsackSolver will do its selection on those
effective values.
Lastly, SelectCoins is modified to use the same value for preselected
inputs for BnB and KnapsackSolver. While it will still use the real
value when subtracting the fee from outputs, this behavior will be
the same regardless of the algo used for selecting additional inputs.
The fees for transaction overhead and recipient outputs are now included
in nTargetValue instead of being a separate parameter. For the coin
selection algorithms, it doesn't matter that these are separate as in
either case, the algorithm needs to select enough to cover these fees.
Note that setting nValueToSelect is changed as it now includes
not_input_fees. Without the change to how nValueToSelect is increased
for KnapsackSolver, this would result in overpaying fees. The change to
increase by the difference between nFeeRet and not_input_fees allows
this to have the same behavior as previously.
Additionally, because we assume that KnapsackSolver will always find a
solution that requires change (we assume that BnB always finds a
non-change solution), we also include the fee for the change output in
KnapsackSolver's target. As part of this, we also use the changeless
nFeeRet when iterating for KnapsackSolver. This is because we include
the change fee when doing KnapsackSolver, so nFeeRet on further
iterations won't include the change fee.
Simplifies CreateTransactionInternal without changing behavior. Removes
the pick_new_inputs variable by moving the subtract fee from amount
implementation to later in the loop to where it is possible to calculate
the fee for the transaction. This allows the fee to be subtracted from
the outputs within a single iteration, instead of calculating the fee in
the first iteration, and subtracting the fee in the second.
This also removes another scenario where a second iteration of the loop
finds a smaller input set (and thus smaller fees than the first
iteration) with no change and so a third iteration of the loop is done in order to make
a change output that contains the excess fees.
To handle these cases, we always create a change output which contains
the difference between selected input values and the recipient amounts.
Once the transaction fee is calculated, the change output is reduced (in
the normal case) or the recipient amounts are reduced (in the subtract
fee from amount case). All of this is done in a single iteration of the
loop.
This commit does not change behavior, it just moves code from
CWallet::CreateWalletFromFile to CWallet:::AttachChain so it can be updated in
the next commit.
This commit is most easily reviewed with
"git diff -w --color-moved=dimmed_zebra" or by diffing CWallet:::AttachChain
against the previous code with an external diff tool.
To prepare for KnapsackSolver to use effective values, these
calculations are moved out of the BnB if block to allow for them to be
shared with KnapsackSolver in the future.
The fOnlySafe argument to AvailableCoins is now redundant, since #21359
added a similar field inside the CCoinControl struct.
Not all code paths set a CCoinControl instance, but when it's missing we
can default to using only safe inputs which is backwards-compatible.
11d6459b6e rpc: include_unsafe option for fundrawtransaction (t-bast)
Pull request description:
Allow RPC users to opt-in to unsafe inputs when funding a raw transaction.
Applications that need to manage a complex RBF flow (such as lightning nodes using anchor outputs) are very limited if they can only use safe inputs.
I also added this option to `send` and `walletcreatefundedpsbt` who internally delegate to `fundrawtransaction`.
Fixes#21299
ACKs for top commit:
laanwj:
Code review ACK 11d6459b6e
Tree-SHA512: 5e542a4febcfd6f41cf784678ff02ec9282eae2082c274983f72c5ea87b7ebbe1bd5fdc6a020d7a9d5996157754eb4966b8aeb6c1ceebf0b1519f735579b8bac
d66f283ac0 scripted-diff: Replace three dots with ellipsis in the UI strings (Hennadii Stepanov)
Pull request description:
This PR is split from #21463.
The change was suggested on [Transifex.com](https://www.transifex.com/bitcoin/bitcoin/), and it does not touch `LogPrint` and `LogPrintf` calls.
The only comment on #21463 [was](9030e4b5a6 (r597220100)):
> Mind that these messages also end up in the log. In principle the log is already UTF-8 (as are all strings and text in bitcoind). But, just noting, that it might make browsing the log a less pleasant experience on systems with misconfigured locale like some BSDs by default.
ACKs for top commit:
laanwj:
ACK d66f283ac0
Tree-SHA512: 5ab1cb3160f3f996f1ad7d7486662da3eb7f06a857f4a1874963ce10caed5b86b0ad6151b1b9ebeb2b8aa5f0c85efad3b768ea9cafe5db86f78f88912b756d1e
Allow RPC users to opt-in to unsafe inputs when funding a raw transaction.
Applications that need to manage a complex RBF flow (such as lightning
nodes using anchor outputs) are very limited if they can only use safe inputs.
Fixes#21299
Rather than 3 different messages that are confusing / leak
implementation details, use a single message, that is similar to other
wallet related messages. i.e:
"Compiled without sqlite support (required for descriptor wallets)".
ebc4ab721b refactor: post Optional<> removal cleanups (fanquake)
57e980d13c scripted-diff: remove Optional & nullopt (fanquake)
Pull request description:
Same rationale & motivation as #21404, which turned out to be quite low in the number of potential conflicts. Lets see what the bot has to say here.
ACKs for top commit:
practicalswift:
cr ACK ebc4ab721b: patch looks correct
jnewbery:
utACK ebc4ab721b
laanwj:
Code review ACK ebc4ab721b
Tree-SHA512: 550fbeef09b9d35ddefaa805d1755c18c8fd499c4b0f77ebfece8c20296a7abd1cf6c699e2261f92fe3552deeb7555ec2a2287ffe3ab9e98bb9f8612a4d43be3
f9cd2bfbcc Rename CoinSelectionParams::effective_fee to m_effective_feerate (Andrew Chow)
bdd0c2934b wallet: Move discard feerate fetching to CreateTransaction (Andrew Chow)
448d04b931 wallet: Move long term feerate setting to CreateTransaction (Andrew Chow)
e2f429e6bb wallet: Replace nFeeRateNeeded with effective_fee (Andrew Chow)
1a6a0b0dfb wallet: Use existing feerate instead of getting a new one (Andrew Chow)
Pull request description:
During coin selection, there are various places where we need to have a feerate. We need the feerate for the transaction itself, the discard fee rate, and long term feerate. Fetching these each time we need them can lead to a race condition where two feerates that should be the same are actually different. One particular instance where this can happen is during the loop in `CreateTransactionInternal`. After inputs are chosen, the expected transaction fee is calculated using a newly fetched feerate. If `pick_new_inputs == false`, the loop will go again with the assumption that the fee for the transaction remains the same. However because the feerate is fetched again, it is possible that it actually isn't and this causes coin selection to fail.
Instead of fetching the feerate each time it is needed, we fetch them all at once at the top of `CreateTransactionInternal`, store them in `CoinSelectionParams`, and use them where needed.
While some of these fee rates probably don't need this caching, I've done it for consistency and the guarantee that they remain the same.
Fixes#19229
ACKs for top commit:
glozow:
reACK f9cd2bfbcc
fjahr:
Code review re-ACK f9cd2bfbcc
Xekyo:
tACK f9cd2bfbcc
meshcollider:
Code review + test run ACK f9cd2bfbcc
Tree-SHA512: be83ff64ba473c3cdd3469c812e214659b6e2a9584c22ed2b1595618fce0d4b35d0901e61068cd1069fc1a8fb911db01dd7312d05c3b8cbafbe2504ab7a3e863
Instead of fetching the discard feerate for each SelectCoinsMinConf
iteration, fetch and cache it once during CreateTransaction so that it
is shared for each SelectCoinsMinConf through
coin_selection_params.m_discard_feerate.
Does not change behavior.
Instead of setting the long term feerate for each SelectCoinsMinConf
iteration, set it once during CreateTransaction and let it be shared
with each SelectCoinsMinConf through
coin_selection_params.m_long_term_feerate.
Does not change behavior.
Make sure that all fee calculations use the same feerate.
coin_selection_params.effective_fee is the variable we use for all fee
calculations, so get rid of remaining nFeeRateNeeded usages and just
directly set coin_selection_params.effective_fee.
Does not change behavior.
During each loop of CreateTransaction, instead of constantly getting a
new feerate, use the feerate that we have already fetched for all
fee calculations. Thix fixes a race condition where the feerate required
changes during each iteration of the loop.
This commit changes behavior as the "Fee estimation failed" error will
now take priority over "Signing transaction failed".
fa4e088cba wallet: Mark replaced tx to not be in the mempool anymore (MarcoFalke)
Pull request description:
The wallet does not mark the replaced tx as out-of-mempool. This causes failures in user scripts, because later RPCs may depend on this state change from `bumpfee`.
For example, the following might fail on current master:
```
txid = sendtoaddress(...)
bumpfee(txid)
abandontransaction(txid) # fails because txid is still marked as "in mempool"
```
Fixes#18831
ACKs for top commit:
meshcollider:
utACK fa4e088cba
ryanofsky:
Code review ACK fa4e088cba, and previous ACK faeedff5c87091fd83d2fb2b29eb49c948363f29 is also still valid in case there's a preference for the original fix
Tree-SHA512: 9858f40f5fb5a43a7b584b5c4268b6befa82e6a84583be5206fe721bcb6c255e8d35479d347d0b9aed72703df49887c02b14ab680e8efdd28b90dd6b93d9439a
48a0319bab Add a test that selects too large if BnB is used (Andrew Chow)
3e69939b78 Fail if maximum weight is too large (Andrew Chow)
51e2cd322c Have CalculateMaximumSignedTxSize also compute tx weight (Andrew Chow)
Pull request description:
Currently the `Transaction too large` is calculated on the transaction that is returned from `CreateTransaction`. This does not make sense for when `CreateTransaction` is being used for `fundrawtransaction` as no signing occurs so the final returned transaction is missing signatures. Thus users may successfully fund a transaction but fail to broadcast it after it has been fully signed.
So instead we should figure out whether the transaction we are funding will be too large after it is signed. We can do this by having `CalculateMaximumSignedTxSize` also return the transaction weight and then comparing that weight against the maximum weight.
ACKs for top commit:
instagibbs:
ACK 48a0319bab
meshcollider:
utACK 48a0319bab
Xekyo:
utACK with nits 48a0319bab
Tree-SHA512: 1700c60b07f67e2d5c591c5ccd131ac9f1861fab3def961c3c9c4b3281ec1063fe8e4f0f7f1038cac72692340856406bcee8fb45c8104d2ad34357a0ec878ac7
5d4597666d Rewrite OutputGroups to be clearer and to use scriptPubKeys (Andrew Chow)
f6b3052739 Explicitly filter out partial groups when we don't want them (Andrew Chow)
416d74fb16 Move OutputGroup positive only filtering into Insert (Andrew Chow)
d895e98b59 Move EligibleForSpending into GroupOutputs (Andrew Chow)
99b399aba5 Move fee setting of OutputGroup to Insert (Andrew Chow)
6148a8acda Move GroupOutputs into SelectCoinsMinConf (Andrew Chow)
2acad03657 Remove OutputGroup non-default constructors (Andrew Chow)
Pull request description:
Even after #17458, we still deal with setting fees of an `OutputGroup` and filtering the `OutputGroup` outside of the struct. We currently make all of the `OutputGroup`s in `SelectCoins` and then copy and modify them within each `SelectCoinsMinConf` scenario. This PR changes this to constructing the `OutputGroup`s within the `SelectCoinsMinConf` so that the scenario can be taken into account during the group construction. Furthermore, setting of fees and filtering for effective value is moved into `OutputGroup::Insert` itself so that we don't add undesirable outputs to an `OutputGroup` rather than deleting them afterwards.
To facilitate fee calculation and effective value filtering during `OutputGroup::Insert`, `OutputGroup` now takes the feerates in its constructor and computes the fees and effective value for each output during `Insert`.
While removing `OutputGroup`s in accordance with the `CoinEligibilityFilter` still requires creating the `OutputGroup`s first, we can do that within the function that makes them - `GroupOutput`s.
ACKs for top commit:
Xekyo:
Code review ACK: 5d4597666d
fjahr:
Code review ACK 5d4597666d
meshcollider:
Light utACK 5d4597666d
Tree-SHA512: 35965b6d49a87f4ebb366ec4f00aafaaf78e9282481ae2c9682b515a3a9f2cbcd3cd6e202fee29489d48fe7f3a7cede4270796f5e72bbaff76da647138fb3059
