Try scratch slice

x/incentives/keeper/distribute.go

@@ -773,7 +773,7 @@ func (k Keeper) handleGroupPostDistribute(ctx sdk.Context, groupGauge types.Gaug
 }
 
 // getDistributeToBaseLocks takes a gauge along with cached period locks by denom and returns locks that must be distributed to
-func (k Keeper) getDistributeToBaseLocks(ctx sdk.Context, gauge types.Gauge, cache map[string][]lockuptypes.PeriodLock) []*lockuptypes.PeriodLock {
+func (k Keeper) getDistributeToBaseLocks(ctx sdk.Context, gauge types.Gauge, cache map[string][]lockuptypes.PeriodLock, scratchSlice *[]*lockuptypes.PeriodLock) []*lockuptypes.PeriodLock {
 	// if gauge is empty, don't get the locks
 	if gauge.Coins.Empty() {
 		return []*lockuptypes.PeriodLock{}
@@ -788,7 +788,7 @@ func (k Keeper) getDistributeToBaseLocks(ctx sdk.Context, gauge types.Gauge, cac
 	// get this from memory instead of hitting iterators / underlying stores.
 	// due to many details of cacheKVStore, iteration will still cause expensive IAVL reads.
 	allLocks := cache[distributeBaseDenom]
-	return FilterLocksByMinDuration(allLocks, gauge.DistributeTo.Duration)
+	return FilterLocksByMinDuration(allLocks, gauge.DistributeTo.Duration, scratchSlice)
 }
 
 // Distribute distributes coins from an array of gauges to all eligible locks and pools in the case of "NoLock" gauges.
@@ -799,10 +799,11 @@ func (k Keeper) Distribute(ctx sdk.Context, gauges []types.Gauge) (sdk.Coins, er
 
 	locksByDenomCache := make(map[string][]lockuptypes.PeriodLock)
 	totalDistributedCoins := sdk.NewCoins()
+	scratchSlice := make([]*lockuptypes.PeriodLock, 0, 10000)
 
 	for _, gauge := range gauges {
 		var gaugeDistributedCoins sdk.Coins
-		filteredLocks := k.getDistributeToBaseLocks(ctx, gauge, locksByDenomCache)
+		filteredLocks := k.getDistributeToBaseLocks(ctx, gauge, locksByDenomCache, &scratchSlice)
 		// send based on synthetic lockup coins if it's distributing to synthetic lockups
 		var err error
 		if lockuptypes.IsSyntheticDenom(gauge.DistributeTo.Denom) {

x/incentives/keeper/iterator.go

@@ -63,8 +63,9 @@ func (k Keeper) FinishedGaugesIterator(ctx sdk.Context) sdk.Iterator {
 }
 
 // FilterLocksByMinDuration returns locks whose lock duration is greater than the provided minimum duration.
-func FilterLocksByMinDuration(locks []lockuptypes.PeriodLock, minDuration time.Duration) []*lockuptypes.PeriodLock {
-	filteredLocks := make([]*lockuptypes.PeriodLock, 0, len(locks))
+func FilterLocksByMinDuration(locks []lockuptypes.PeriodLock, minDuration time.Duration, scratchSlice *[]*lockuptypes.PeriodLock) []*lockuptypes.PeriodLock {
+	*scratchSlice = (*scratchSlice)[:0]
+	filteredLocks := *scratchSlice
 	for i := range locks {
 		if locks[i].Duration >= minDuration {
 			filteredLocks = append(filteredLocks, &locks[i])

x/incentives/keeper/iterator_test.go

@@ -27,7 +27,8 @@ func TestFilterLocksByMinDuration(t *testing.T) {
 		}
 	}
 
-	filteredLocks := keeper.FilterLocksByMinDuration(locks, minDuration)
+	scratchSlice := []*lockuptypes.PeriodLock{}
+	filteredLocks := keeper.FilterLocksByMinDuration(locks, minDuration, &scratchSlice)
 
 	require.Equal(t, len(locks), len(filteredLocks))