Replace coin selection fallback strategy with Single Random Draw

achow101 commented at 3:24 am on May 23, 2018: member

When BnB selection fails to find an exact match, we fall back to the original Bitcoin Core algorithm. This PR replaces that fallback with the Single Random Draw strategy. Additionally, because SRD uses effective values, the previous fee increasing loop thing is now removed and effective value is used everywhere.

Some tests may fail spuriously because they may rely on semi-deterministic behavior from the original coin selection algorithm. I have been able to fix the ones that fail the most, but others may still have issues. Please let me know if you see any tests fail for coin selection reasons (e.g. insufficient funds, missing inputs, etc.) and I will try to fix them.

I will be working on doing simulations this week and will post the data once I finish them.

achow101 commented at 3:24 am on May 23, 2018: member

cc @Xekyo @instagibbs

fanquake added the label Wallet on May 23, 2018

achow101 force-pushed on May 23, 2018

in src/wallet/coinselection.cpp:320 in 7fd7c1b93c outdated

315+        value_ret += utxo.txout.nValue;
316+        out_set.insert(utxo);
317+
318+        // We have enough coins, stop selecting
319+        if (curr_value >= target_value + not_input_fees) {
320+            break;

Empact commented at 10:30 am on May 23, 2018:

Could return true here, return false if the loop exhausts, to avoid duplicating the condition.

achow101 commented at 4:56 pm on May 23, 2018:

Done

in src/wallet/wallet.cpp:2466 in a603558b10 outdated

2512@@ -2513,26 +2513,21 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibil
2513 
2514     // Start with BnB. If that fails, use SRD
2515     if (SelectCoinsBnB(utxo_pool, nTargetValue, cost_of_change, setCoinsRet, nValueRet, not_input_fees)) {
2516-        bnb_used = true;
2517         return true;
2518     } else {
2519-        bnb_used = false;
2520         return SingleRandomDraw(nTargetValue, utxo_pool, setCoinsRet, nValueRet, not_input_fees);

Empact commented at 10:36 am on May 23, 2018:

Could collapse this to boolean fallback at this point.

achow101 commented at 4:57 pm on May 23, 2018:

Done

in src/wallet/wallet.h:856 in 35830934fd outdated

848@@ -849,8 +849,8 @@ class CWallet final : public CCryptoKeyStore, public CValidationInterface
849      * completion the coin set and corresponding actual target value is
850      * assembled
851      */
852-    bool SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibility_filter, std::vector<COutput> vCoins,
853-        std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CoinSelectionParams& coin_selection_params, bool& bnb_used) const;
854+    bool SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibilty_filter, std::vector<COutput> vCoins,

Empact commented at 10:56 am on May 23, 2018:

eligibilty_filter typo

achow101 commented at 4:57 pm on May 23, 2018:

Fixed

achow101 force-pushed on May 23, 2018

in src/wallet/coinselection.cpp:305 in f03ae69ed5 outdated

297@@ -298,3 +298,27 @@ bool KnapsackSolver(const CAmount& nTargetValue, std::vector<CInputCoin>& vCoins
298 
299     return true;
300 }
301+
302+/*
303+ * Randomly selects coins until the target value is exceeded. Uses effective values
304+ */
305+bool SingleRandomDraw(const CAmount& target_value, std::vector<CInputCoin>& utxo_pool, std::set<CInputCoin>& out_set, CAmount& value_ret, CAmount not_input_fees)

instagibbs commented at 10:20 pm on June 4, 2018:

non_input_fees? It’s not “not fees”, rather “non-input”. Easier for me to read.

achow101 commented at 5:31 am on June 5, 2018:

Done

in src/wallet/wallet.cpp:2513 in 1ed31565b3 outdated

2508@@ -2509,9 +2509,10 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibil
2509     // Calculate the fees for things that aren't inputs
2510     CAmount not_input_fees = coin_selection_params.effective_fee.GetFee(coin_selection_params.tx_noinputs_size);
2511 
2512-    if (coin_selection_params.use_bnb) {
2513+    // Start with BnB. If that fails, use SRD
2514+    if (SelectCoinsBnB(utxo_pool, nTargetValue, cost_of_change, setCoinsRet, nValueRet, not_input_fees)) {

instagibbs commented at 10:29 pm on June 4, 2018:

I think this new logic means that non-BnB will be tried more often? Instead of trying all variants of BnB(6 confirms, 1 confirm, small chain, etc), we seem to be trying 6 confirms for BnB, then 6 confirms for non-BnB

achow101 commented at 5:32 am on June 5, 2018:

Hmm, yes, that appears to be what is happening. I guess this depends on whether we want to select an exact match for coins with less confirmatoins, or whether we want confirmations over exact match.

sipa commented at 6:03 pm on June 9, 2018:

This is a good point. Perhaps a solution is to add a use_bnb argument to SelectCoinsMinConf (but not as part CoinSelectionParams), and then have a sequence of attempts with and without use_bnb in SelectCoins?

instagibbs commented at 7:32 pm on June 14, 2018:

I prefer the behavior in master due to privacy reasons of change-less transactions.

achow101 commented at 1:52 am on June 16, 2018:

I have implemented this change.

in src/wallet/wallet.cpp:2892 in f84301bac5 outdated

2886@@ -2916,6 +2887,40 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac
2887             for (const auto& coin : setCoins)
2888                 txNew.vin.push_back(CTxIn(coin.outpoint,CScript(),
2889                                           nSequence));
2890+
2891+            // Fill vout
2892+            bool fFirst = true;

instagibbs commented at 10:46 pm on June 4, 2018:

maybe rename to first_output

achow101 commented at 5:32 am on June 5, 2018:

Done

in src/wallet/wallet.cpp:2502 in 77f7a98050 outdated

2498@@ -2498,7 +2499,7 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibil
2499             continue;
2500 
2501         CInputCoin coin(output.tx->tx, output.i);
2502-        coin.effective_value = coin.txout.nValue - (output.nInputBytes < 0 ? 0 : coin_selection_params.effective_fee.GetFee(output.nInputBytes));
2503+        coin.effective_value = coin.txout.nValue - (output.nInputBytes < 0 || !use_effective ? 0 : coin_selection_params.effective_fee.GetFee(output.nInputBytes));

instagibbs commented at 10:58 pm on June 4, 2018:

parenthesis please

achow101 commented at 5:32 am on June 5, 2018:

Done

instagibbs commented at 11:02 pm on June 4, 2018: member

“Calculate the transaction fees” <— this commit probably needs more description, not sure what it’s doing.

instagibbs commented at 11:02 pm on June 4, 2018: member

Some thoughts.

achow101 force-pushed on Jun 5, 2018

achow101 commented at 5:33 am on June 5, 2018: member

“Calculate the transaction fees” <— this commit probably needs more description, not sure what it’s doing.

Reworded, hopefully it’s better.

Empact commented at 6:19 am on June 8, 2018: member

nit: Somewhat better to revert the merge commit 9552dfb rather than the 2 pr commits, to be explicit that the whole PR was reverted (and which one).

in src/wallet/coinselection.cpp:169 in 50000b1239 outdated

211-}
212-
213-bool KnapsackSolver(const CAmount& nTargetValue, std::vector<CInputCoin>& vCoins, std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet)
214+/*
215+ * Randomly selects coins until the target value is exceeded. Uses effective values
216+ */

Empact commented at 6:19 am on June 8, 2018:

nit: Better to document in the header, and use doxygen comment /**

achow101 commented at 11:17 pm on June 8, 2018:

Done

in src/wallet/test/coinselector_tests.cpp:253 in 50000b1239 outdated

248@@ -554,13 +249,11 @@ BOOST_AUTO_TEST_CASE(SelectCoins_test)
249         CAmount target = rand.randrange(balance - 1000) + 1000;
250 
251         // Perform selection
252-        CoinSelectionParams coin_selection_params_knapsack(false, 34, 148, CFeeRate(0), 0);
253-        CoinSelectionParams coin_selection_params_bnb(true, 34, 148, CFeeRate(0), 0);
254+
255+        CoinSelectionParams coin_selection_params_bnb(34, 148, CFeeRate(0), 0);

Empact commented at 6:20 am on June 8, 2018:

_bnb probably no longer relevant

achow101 commented at 11:17 pm on June 8, 2018:

Removed here and elsewhere

in src/wallet/test/coinselector_tests.cpp:217 in 50000b1239 outdated

213@@ -216,316 +214,13 @@ BOOST_AUTO_TEST_CASE(bnb_search_test)
214     }
215 
216     // Make sure that effective value is working in SelectCoinsMinConf when BnB is used
217-    CoinSelectionParams coin_selection_params_bnb(true, 0, 0, CFeeRate(3000), 0);
218+    CoinSelectionParams coin_selection_params_bnb(0, 0, CFeeRate(3000), 0);

Empact commented at 6:21 am on June 8, 2018:

Same

in src/wallet/wallet.cpp:2536 in 35ce099536 outdated

2528@@ -2529,14 +2529,18 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
2529             if (!out.fSpendable)
2530                  continue;
2531             nValueRet += out.tx->tx->vout[out.i].nValue;
2532-            setCoinsRet.insert(CInputCoin(out.tx->tx, out.i));
2533+            CInputCoin coin(out.tx->tx, out.i);
2534+            coin.effective_value = coin.txout.nValue - (out.nInputBytes < 0 || !use_effective ? 0 : coin_selection_params.effective_fee.GetFee(out.nInputBytes));

Empact commented at 6:29 am on June 8, 2018:

nit: explicit precedence would be nice here: (out.nInputBytes < 0 || !use_effective)

achow101 commented at 11:17 pm on June 8, 2018:

I thought I did this earlier. Must have gotten lost in a rebase. Fixed.

Empact commented at 9:58 pm on June 14, 2018:

Doesn’t look changed fyi.

achow101 commented at 10:22 pm on June 14, 2018:

How about now?

in src/wallet/wallet.cpp:2572 in 35ce099536 outdated

2572+            nValueFromPresetInputs += preset_it->txout.nValue;
2573+            effective_value_from_presets += preset_it->effective_value;
2574             it = vCoins.erase(it);
2575-        else
2576+        }
2577+        else {

Empact commented at 6:30 am on June 8, 2018:

nit: whitespace

achow101 commented at 11:17 pm on June 8, 2018:

Done

in src/wallet/coinselection.h:35 in 50000b1239 outdated

29@@ -30,9 +30,9 @@ class CInputCoin {
30 
31     COutPoint outpoint;
32     CTxOut txout;
33-    CAmount effective_value;
34-    CAmount fee = 0;
35-    CAmount long_term_fee = 0;
36+    mutable CAmount effective_value;
37+    mutable CAmount fee = 0;
38+    mutable CAmount long_term_fee = 0;

Empact commented at 6:55 am on June 8, 2018:

nit: Better to squash this change into the commit that calls for it

achow101 commented at 11:17 pm on June 8, 2018:

Done

achow101 force-pushed on Jun 8, 2018

achow101 commented at 11:18 pm on June 8, 2018: member

nit: Somewhat better to revert the merge commit 9552dfb rather than the 2 pr commits, to be explicit that the whole PR was reverted (and which one).

Done

in src/wallet/coinselection.cpp:304 in aea9842729 outdated

297@@ -298,3 +298,24 @@ bool KnapsackSolver(const CAmount& nTargetValue, std::vector<CInputCoin>& vCoins
298 
299     return true;
300 }
301+
302+bool SingleRandomDraw(const CAmount& target_value, std::vector<CInputCoin>& utxo_pool, std::set<CInputCoin>& out_set, CAmount& value_ret, CAmount non_input_fees)
303+{
304+    random_shuffle(utxo_pool.begin(), utxo_pool.end(), GetRandInt);

sipa commented at 5:49 pm on June 9, 2018:

Two comments:

Requesting new entropy for each element being sorted may be slow (each call to GetRandInt invokes OpenSSL for randomness) (this also applies to the code you copied, but you’re going to remove that anyway).
It’s overkill to permute all elements, as you’re likely only going to use a few.

For the first, create a FastRandomContext and use that in std::shuffle (rather than random_shuffle):

0std::shuffle(utxo_pool.begin(), utxo_pool.end(), FastRandomContext());`

For the second, you can permute on the fly; for example:

0FastRandomContext ctx;
1for (size_t i = 0; i < utxo_pool.size; ++i) {
2    size_t pos = i + ctx.randrange(utxo_pool.size() - i); // randomly pick one of the remaining elements
3    std::swap(utxo_pool[i], utxo_pool[pos]);
4    const CInputCoin& utxo = utxo_pool[i];
5    ...
6}

achow101 commented at 10:01 pm on June 9, 2018:

Done

in src/wallet/wallet.cpp:2912 in 1a89ac2d03 outdated

2922-            for (const auto& coin : setCoins)
2923-                txNew.vin.push_back(CTxIn(coin.outpoint,CScript(),
2924-                                          nSequence));
2925+                if (nSubtractFeeFromAmount != 0) {
2926+                    // If we are subtracting the fee from the amount, nChange cannot be less than 0 because nFeeRet is not involved.
2927+                    // We need to decrase nFeeRet by the change output fee so that we do not overpay.

sipa commented at 6:07 pm on June 9, 2018:

Typo: decrase

achow101 commented at 10:01 pm on June 9, 2018:

Fixed

achow101 force-pushed on Jun 9, 2018

in src/wallet/coinselection.cpp:171 in 05dfc65a8a outdated

215-{
216-    setCoinsRet.clear();
217-    nValueRet = 0;
218+    FastRandomContext random_ctx;
219+    CAmount curr_value = 0;
220+    for (size_t i = 0; i < utxo_pool.size; ++i) {

sipa commented at 11:57 pm on June 9, 2018:

Travis fails because of size (instead of size()).

achow101 commented at 0:16 am on June 10, 2018:

Oops.

achow101 force-pushed on Jun 10, 2018

achow101 commented at 2:04 am on June 10, 2018: member

I’m not quite sure what is causing the travis failure.

DrahtBot added the label Needs rebase on Jun 11, 2018

MarcoFalke removed the label Needs rebase on Jun 11, 2018

DrahtBot added the label Needs rebase on Jun 11, 2018

achow101 force-pushed on Jun 11, 2018

achow101 commented at 7:02 pm on June 11, 2018: member

Rebased

achow101 force-pushed on Jun 11, 2018

DrahtBot removed the label Needs rebase on Jun 11, 2018

in src/wallet/coinselection.cpp:187 in 4c55a09769 outdated

315+        curr_value += utxo.effective_value;
316+        value_ret += utxo.txout.nValue;
317+        out_set.insert(utxo);
318+
319+        // We have enough coins, stop selecting
320+        if (curr_value >= target_value + non_input_fees) {

Xekyo commented at 3:33 pm on June 12, 2018:

What you’re calling target_value here is not actually the value you’re targeting. How about recipient_amount or payload? Or add the payload, output_fees and tx_overhead_fees into a selection_target per selection style to differentiate between change/no-change?

achow101 commented at 7:48 pm on June 18, 2018:

I renamed it to recipient_amount. I don’t think there needs to be any differentiation between change and no change.

achow101 force-pushed on Jun 12, 2018

achow101 commented at 7:01 pm on June 12, 2018: member

I fixed the test failure.

achow101 force-pushed on Jun 13, 2018

achow101 force-pushed on Jun 14, 2018

achow101 force-pushed on Jun 16, 2018

Xekyo commented at 1:04 am on June 18, 2018: member

There are a few commits in your PR that obsolete previous changes, I only realized that after going through them commit by commit. You may want to rebase differently to tidy that up.

in src/wallet/coinselection.cpp:167 in a8bca48038 outdated

163@@ -164,137 +164,29 @@ bool SelectCoinsBnB(std::vector<CInputCoin>& utxo_pool, const CAmount& target_va
164     return true;
165 }
166 
167-static void ApproximateBestSubset(const std::vector<CInputCoin>& vValue, const CAmount& nTotalLower, const CAmount& nTargetValue,
168-                                  std::vector<char>& vfBest, CAmount& nBest, int iterations = 1000)
169+bool SingleRandomDraw(const CAmount& target_value, std::vector<CInputCoin>& utxo_pool, std::set<CInputCoin>& out_set, CAmount& value_ret, CAmount non_input_fees)

Xekyo commented at 1:07 am on June 18, 2018:

Theoretically, SRD could also produce a result without a change. You could fold the non_input_fees into the target_value, and if you don’t find a perfect match, select more until you have minChange + fee for one output more than target.

achow101 commented at 7:29 pm on June 18, 2018:

I don’t think that this distinction matters. If SRD produces a result without change, the rest of the code will treat it as if BnB had been used, there is no difference for change or no change. I don’t think it is necessary to target a min change or include the change output’s fees in the target.

in src/wallet/wallet.h:855 in a8bca48038 outdated

851@@ -852,7 +852,7 @@ class CWallet final : public CCryptoKeyStore, public CValidationInterface
852      * assembled
853      */
854     bool SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibility_filter, std::vector<COutput> vCoins,
855-        std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CoinSelectionParams& coin_selection_params, bool& bnb_used) const;
856+        std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CoinSelectionParams& coin_selection_params, bool use_effecitve, bool use_bnb) const;

Xekyo commented at 1:09 am on June 18, 2018:

use_effecitve has a typo.

achow101 commented at 7:48 pm on June 18, 2018:

Fixed

in test/functional/rpc_fundrawtransaction.py:360 in a8bca48038 outdated

358+        mempool_tx = self.nodes[0].getrawmempool(True)[txId]
359 
360-        #compare fee
361-        feeDelta = Decimal(fundedTx['fee']) - Decimal(signedFee)
362+        #compare feerates
363+        feeDelta = (Decimal(fundedTx['fee']) / Decimal(len(fundedTx['hex']) / 2)) - (Decimal(mempool_tx['fee']) / mempool_tx['size'])

Xekyo commented at 1:10 am on June 18, 2018:

Shouldn’t this be segwit sensitive? Hex length is only a valid indicator of weight for non-segwit transactions. I guess this test only has legacy transactions?

Since you use the same calculation multiple times, you might want to make a helper function that only takes fundedTx and mempool_tx as params and returns the feeDelta.

achow101 commented at 7:36 pm on June 18, 2018:

The test only uses legacy addresses. I don’t think it is necessary to make a helper function for this.

achow101 force-pushed on Jun 18, 2018

achow101 commented at 7:49 pm on June 18, 2018: member

I squashed down a few commits, hopefully that will make the code easier to review.

achow101 commented at 6:18 pm on June 20, 2018: member

I have done some simulations of this strategy along with a few other strategies of different effective value filtering. Results here: https://gist.github.com/achow101/242470486265d3f21adab08f65b9102c

instagibbs commented at 6:25 pm on June 20, 2018: member

Takeaway from the simulations is that filtering out negative effective values seemingly does near-best in utxo size and the best in fees overall. Latter point is unexpected.

On Wed, Jun 20, 2018 at 2:20 PM Andrew Chow notifications@github.com wrote:

I have done some simulations of this strategy along with a few other strategies of different effective value filtering. Results here: https://gist.github.com/achow101/242470486265d3f21adab08f65b9102c

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/bitcoin/bitcoin/pull/13307#issuecomment-398847615, or mute the thread https://github.com/notifications/unsubscribe-auth/AFgC019Y7wp_GYM3LgpqSHwBROiLZvTFks5t-pJ4gaJpZM4UJteu .

achow101 commented at 6:29 pm on June 20, 2018: member

The main issue here is the minimum change. SRD currently does not target a minimum change which can result in very small, near dust, change outputs. So the question is really what we should target as min change.

DrahtBot added the label Needs rebase on Jun 30, 2018

achow101 commented at 7:44 pm on July 3, 2018: member

Rebased

achow101 force-pushed on Jul 3, 2018

sipa commented at 11:03 pm on July 3, 2018: member

As suggested on https://iohk.io/blog/self-organisation-in-coin-selection/ it may be worth it to aim for change up to twice the amount we’re trying to send, to avoid grinding down change too much.

Of course, that doesn’t work whenever the total (effective) amount in the wallet is less than twice the amount we’re trying to send. A reasonably simple function to reconcile the two is C = P*(1 - P/B), where P is the amount we’re sending, B is the total effective balance, and C is the maximum change size we’re targetting. For small P/B, this will result in change close to P, but never aim for more than we have.

achow101 commented at 2:32 am on July 6, 2018: member

Using @sipa’s function, I have found though simulations that the smallest change created is much larger than what simple SRD produces. However the problem with a higher mean number of UTXOs persists and is slightly worse with this modification. But fees are still the same, and we are unlikely to be grinding things into dust. The question then is are we okay with having more UTXOs or should we attempt to consolidate as much as currently done.

Part of the difference is due to the fact that currently we spend dust outputs, but simulations show that even this does not entirely account for the higher number of UTXOs.

achow101 force-pushed on Jul 7, 2018

achow101 commented at 0:38 am on July 7, 2018: member

Fixed the test failure.

DrahtBot removed the label Needs rebase on Jul 7, 2018

DrahtBot added the label Needs rebase on Jul 24, 2018

Revert "Merge #12694: Actually disable BnB when there are preset inputs"

This reverts commit 9552dfb1f6326b97ae05efb8af503eb7776a2d59, reversing
changes made to f686002a8eba820a40ac2f34a6e8f57b2b5cc54c.

2f4ab05c5a

Implement the SingleRandomDraw coin selection method

SingleRandomDraw randomly chooses UTXOs until there is sufficient
effective value.

65b535b862

Replace the coin selection fallback with SRD

Replaces the knapsack solver fallback with the SRD fallback. Also
changes SelectCoinsMinConf to use exclusively effective value to
work with BnB and SRD

ffd71565b3

Remove KnapsackSolver and related tests 02b288f91f

Have SelectCoinsMinConf figure out when to use BnB or SRD

Instead of the caller telling SelectCoinsMinConf when to use BnB
or the fallback, have SelectCoinsMinConf do it itself. This removes
the use_bnb field of coin_selection_params

33737a5a70

Remove the CreateTransaction loop and fee checking things

We are now using effective value for coin selection, so there is no
need for the loop or any of the fee checking things that were done
within it. All fees ard handled by the effective value selection

Move vout filling to after coins are selected so that the transaction
fee is actually known to handle when users want to subtract the fee
from the outputs.

c1c24d60bc

Don't use effective values when we are subtracting the fee from the amount ae9a8e19f2

Remove bnb_used

bnb_used is no longer necessary since we account for fees when
calculating how much change there is

8ecb6340d6

handle preset inputs

For preset inputs, use their effective values

6989b9df81

Split change output creation from fee calculation for change e3903f3aa5

Make tests work with non-deterministic coin selection

Fix tests that relied on non-deterministic coin selection to be able
to handle the random coin selection.

339d977fbd

achow101 force-pushed on Aug 17, 2018

achow101 commented at 9:15 pm on August 17, 2018: member

Rebased

DrahtBot removed the label Needs rebase on Aug 17, 2018

DrahtBot commented at 6:53 pm on September 7, 2018: member

#14156 ([WIP] refactor: Make explicit CMutableTransaction -> CTransaction conversion. by lucash-dev)
#13558 (Drop unused GetType() from CSizeComputer by Empact)
#13546 (wallet: Avoid potential use of uninitialized value bnb_used in CWallet::CreateTransaction(…) by practicalswift)
#13419 ([tests] Speed up knapsack_solver_test by not recreating wallet 100 times. by lucash-dev)
#13057 (refactor pre-selected coin code by instagibbs)
#11652 (Add missing locks: validation.cpp + related by practicalswift)
#11634 (wallet: Add missing cs_wallet/cs_KeyStore locks to wallet by practicalswift)
#10973 (Refactor: separate wallet from node by ryanofsky)
#9381 (Remove CWalletTx merging logic from AddToWallet by ryanofsky)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

DrahtBot added the label Needs rebase on Sep 11, 2018

DrahtBot commented at 8:38 am on September 11, 2018: member

DrahtBot commented at 7:23 pm on December 12, 2018: member

DrahtBot added the label Up for grabs on Dec 12, 2018

DrahtBot closed this on Dec 12, 2018

laanwj removed the label Needs rebase on Oct 24, 2019

MarcoFalke locked this on Dec 16, 2021

MarcoFalke removed the label Up for grabs on Mar 22, 2022

Replace coin selection fallback strategy with Single Random Draw #13307