Fix Reduce Equalise order in offhchain phragmen (#5892)

This commit is contained in:
Kian Paimani
2020-05-05 13:50:42 +02:00
committed by GitHub
parent 1f7f8abb33
commit 16af2642ff
5 changed files with 44 additions and 31 deletions
+3
View File
@@ -2338,6 +2338,9 @@ impl<T: Trait> Module<T> {
// candidates.
let snapshot_length = <SnapshotValidators<T>>::decode_len()
.map_err(|_| Error::<T>::SnapshotUnavailable)?;
// check the winner length only here and when we know the length of the snapshot validators
// length.
let desired_winners = Self::validator_count().min(snapshot_length as u32);
ensure!(winners.len() as u32 == desired_winners, Error::<T>::PhragmenBogusWinnerCount);
+14 -2
View File
@@ -834,7 +834,7 @@ pub(crate) fn horrible_phragmen_with_post_processing(
// Ensure that this result is worse than seq-phragmen. Otherwise, it should not have been used
// for testing.
let score = {
let (_, _, better_score) = prepare_submission_with(true, |_| {});
let (_, _, better_score) = prepare_submission_with(true, 0, |_| {});
let support = build_support_map::<AccountId>(&winners, &staked_assignment).0;
let score = evaluate_support(&support);
@@ -875,6 +875,7 @@ pub(crate) fn horrible_phragmen_with_post_processing(
// cannot do it since we want to have `tweak` injected into the process.
pub(crate) fn prepare_submission_with(
do_reduce: bool,
iterations: usize,
tweak: impl FnOnce(&mut Vec<StakedAssignment<AccountId>>),
) -> (CompactAssignments, Vec<ValidatorIndex>, PhragmenScore) {
// run phragmen on the default stuff.
@@ -882,14 +883,25 @@ pub(crate) fn prepare_submission_with(
winners,
assignments,
} = Staking::do_phragmen::<OffchainAccuracy>().unwrap();
let winners = winners.into_iter().map(|(w, _)| w).collect::<Vec<AccountId>>();
let winners = sp_phragmen::to_without_backing(winners);
let stake_of = |who: &AccountId| -> VoteWeight {
<CurrencyToVoteHandler as Convert<Balance, VoteWeight>>::convert(
Staking::slashable_balance_of(&who)
)
};
let mut staked = sp_phragmen::assignment_ratio_to_staked(assignments, stake_of);
let (mut support_map, _) = build_support_map::<AccountId>(&winners, &staked);
if iterations > 0 {
sp_phragmen::equalize(
&mut staked,
&mut support_map,
Zero::zero(),
iterations,
);
}
// apply custom tweaks. awesome for testing.
tweak(&mut staked);
@@ -168,13 +168,7 @@ pub fn prepare_submission<T: Trait>(
<Module<T>>::slashable_balance_of_vote_weight,
);
// reduce
if do_reduce {
reduce(&mut staked);
}
let (mut support_map, _) = build_support_map::<T::AccountId>(&winners, &staked);
// equalize a random number of times.
let iterations_executed = match T::MaxIterations::get() {
0 => {
@@ -194,6 +188,10 @@ pub fn prepare_submission<T: Trait>(
}
};
// reduce
if do_reduce {
reduce(&mut staked);
}
// Convert back to ratio assignment. This takes less space.
let low_accuracy_assignment = sp_phragmen::assignment_staked_to_ratio(staked);
+20 -20
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@@ -2917,7 +2917,7 @@ mod offchain_phragmen {
assert_eq!(Staking::era_election_status(), ElectionStatus::Open(12));
assert!(Staking::snapshot_validators().is_some());
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_ok!(Staking::submit_election_solution(
Origin::signed(10),
winners,
@@ -2960,7 +2960,7 @@ mod offchain_phragmen {
run_to_block(14);
assert_eq!(Staking::era_election_status(), ElectionStatus::Open(12));
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_ok!(Staking::submit_election_solution(
Origin::signed(10),
winners,
@@ -3007,7 +3007,7 @@ mod offchain_phragmen {
// create all the indices just to build the solution.
Staking::create_stakers_snapshot();
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
Staking::kill_stakers_snapshot();
assert_noop!(
@@ -3036,7 +3036,7 @@ mod offchain_phragmen {
run_to_block(12);
// a good solution
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_ok!(Staking::submit_election_solution(
Origin::signed(10),
winners,
@@ -3083,7 +3083,7 @@ mod offchain_phragmen {
));
// a better solution
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_ok!(Staking::submit_election_solution(
Origin::signed(10),
winners,
@@ -3189,7 +3189,7 @@ mod offchain_phragmen {
ext.execute_with(|| {
run_to_block(12);
// put a good solution on-chain
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_ok!(Staking::submit_election_solution(
Origin::signed(10),
winners,
@@ -3235,7 +3235,7 @@ mod offchain_phragmen {
run_to_block(12);
ValidatorCount::put(3);
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
ValidatorCount::put(4);
assert_eq!(winners.len(), 3);
@@ -3266,7 +3266,7 @@ mod offchain_phragmen {
run_to_block(12);
ValidatorCount::put(3);
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
ValidatorCount::put(4);
assert_eq!(winners.len(), 3);
@@ -3296,7 +3296,7 @@ mod offchain_phragmen {
build_offchain_phragmen_test_ext();
run_to_block(12);
let (compact, winners, score) = prepare_submission_with(true, |_| {});
let (compact, winners, score) = prepare_submission_with(true, 2, |_| {});
assert_eq!(winners.len(), 4);
@@ -3325,7 +3325,7 @@ mod offchain_phragmen {
assert_eq!(Staking::snapshot_nominators().unwrap().len(), 5 + 4);
assert_eq!(Staking::snapshot_validators().unwrap().len(), 4);
let (mut compact, winners, score) = prepare_submission_with(true, |_| {});
let (mut compact, winners, score) = prepare_submission_with(true, 2, |_| {});
// index 9 doesn't exist.
compact.votes1.push((9, 2));
@@ -3358,7 +3358,7 @@ mod offchain_phragmen {
assert_eq!(Staking::snapshot_nominators().unwrap().len(), 5 + 4);
assert_eq!(Staking::snapshot_validators().unwrap().len(), 4);
let (mut compact, winners, score) = prepare_submission_with(true, |_| {});
let (mut compact, winners, score) = prepare_submission_with(true, 2, |_| {});
// index 4 doesn't exist.
compact.votes1.push((3, 4));
@@ -3391,7 +3391,7 @@ mod offchain_phragmen {
assert_eq!(Staking::snapshot_nominators().unwrap().len(), 5 + 4);
assert_eq!(Staking::snapshot_validators().unwrap().len(), 4);
let (compact, _, score) = prepare_submission_with(true, |_| {});
let (compact, _, score) = prepare_submission_with(true, 2, |_| {});
// index 4 doesn't exist.
let winners = vec![0, 1, 2, 4];
@@ -3424,7 +3424,7 @@ mod offchain_phragmen {
assert_eq!(Staking::snapshot_nominators().unwrap().len(), 5 + 4);
assert_eq!(Staking::snapshot_validators().unwrap().len(), 4);
let (compact, winners, score) = prepare_submission_with(true, |a| {
let (compact, winners, score) = prepare_submission_with(true, 2, |a| {
a.iter_mut()
.find(|x| x.who == 5)
// all 3 cannot be among the winners. Although, all of them are validator
@@ -3457,7 +3457,7 @@ mod offchain_phragmen {
build_offchain_phragmen_test_ext();
run_to_block(12);
let (compact, winners, score) = prepare_submission_with(true, |a| {
let (compact, winners, score) = prepare_submission_with(true, 2, |a| {
// mutate a self vote to target someone else. That someone else is still among the
// winners
a.iter_mut().find(|x| x.who == 11).map(|x| {
@@ -3493,7 +3493,7 @@ mod offchain_phragmen {
build_offchain_phragmen_test_ext();
run_to_block(12);
let (compact, winners, score) = prepare_submission_with(true, |a| {
let (compact, winners, score) = prepare_submission_with(true, 2, |a| {
// Remove the self vote.
a.retain(|x| x.who != 11);
// add is as a new double vote
@@ -3531,7 +3531,7 @@ mod offchain_phragmen {
// Note: we don't reduce here to be able to tweak votes3. votes3 will vanish if you
// reduce.
let (mut compact, winners, score) = prepare_submission_with(false, |_| {});
let (mut compact, winners, score) = prepare_submission_with(false, 0, |_| {});
if let Some(c) = compact.votes3.iter_mut().find(|x| x.0 == 0) {
// by default it should have been (0, [(2, 33%), (1, 33%)], 0)
@@ -3573,7 +3573,7 @@ mod offchain_phragmen {
build_offchain_phragmen_test_ext();
run_to_block(12);
let (compact, winners, score) = prepare_submission_with(false, |a| {
let (compact, winners, score) = prepare_submission_with(false, 0, |a| {
// 3 only voted for 20 and 40. We add a fake vote to 30. The stake sum is still
// correctly 100.
a.iter_mut()
@@ -3635,7 +3635,7 @@ mod offchain_phragmen {
run_to_block(32);
// a solution that has been prepared after the slash.
let (compact, winners, score) = prepare_submission_with(false, |a| {
let (compact, winners, score) = prepare_submission_with(false, 0, |a| {
// no one is allowed to vote for 10, except for itself.
a.into_iter()
.filter(|s| s.who != 11)
@@ -3654,7 +3654,7 @@ mod offchain_phragmen {
));
// a wrong solution.
let (compact, winners, score) = prepare_submission_with(false, |a| {
let (compact, winners, score) = prepare_submission_with(false, 0, |a| {
// add back the vote that has been filtered out.
a.push(StakedAssignment {
who: 1,
@@ -3688,7 +3688,7 @@ mod offchain_phragmen {
build_offchain_phragmen_test_ext();
run_to_block(12);
let (compact, winners, mut score) = prepare_submission_with(true, |_| {});
let (compact, winners, mut score) = prepare_submission_with(true, 2, |_| {});
score[0] += 1;
assert_noop!(
+3 -3
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@@ -599,11 +599,11 @@ pub fn evaluate_support<AccountId>(
) -> PhragmenScore {
let mut min_support = ExtendedBalance::max_value();
let mut sum: ExtendedBalance = Zero::zero();
// NOTE: this will probably saturate but using big num makes it even slower. We'll have to see.
// This must run on chain..
// NOTE: The third element might saturate but fine for now since this will run on-chain and need
// to be fast.
let mut sum_squared: ExtendedBalance = Zero::zero();
for (_, support) in support.iter() {
sum += support.total;
sum = sum.saturating_add(support.total);
let squared = support.total.saturating_mul(support.total);
sum_squared = sum_squared.saturating_add(squared);
if support.total < min_support {