Fix unclosed tickers/timers (#7190)

* fix resource leak
* fixes leak in blocks fetcher
* client/validator release ticker resorces
* powchain, more straightforward ticker closing
* adds missing ticker.stop() calls
* more straightforward ticker closing
* Merge refs/heads/master into fix-unclosed-tickers-timers
* Merge refs/heads/master into fix-unclosed-tickers-timers
* Merge refs/heads/master into fix-unclosed-tickers-timers
* gofmt issues introduced in #7176

beacon-chain/operations/attestations/prepare_forkchoice.go

@@ -22,6 +22,7 @@ var prepareForkChoiceAttsPeriod = slotutil.DivideSlotBy(3 /* times-per-slot */)
 // every prepareForkChoiceAttsPeriod.
 func (s *Service) prepareForkChoiceAtts() {
 	ticker := time.NewTicker(prepareForkChoiceAttsPeriod)
+	defer ticker.Stop()
 	for {
 		ctx := context.Background()
 		select {

beacon-chain/operations/attestations/prune_expired.go

@@ -10,14 +10,14 @@ import (
 // pruneAttsPool prunes attestations pool on every slot interval.
 func (s *Service) pruneAttsPool() {
 	ticker := time.NewTicker(s.pruneInterval)
+	defer ticker.Stop()
 	for {
 		select {
 		case <-ticker.C:
 			s.pruneExpiredAtts()
 			s.updateMetrics()
 		case <-s.ctx.Done():
 			log.Debug("Context closed, exiting routine")
-			ticker.Stop()
 			return
 		}
 	}

beacon-chain/p2p/peers/scorer_manager_test.go

@@ -245,6 +245,7 @@ func TestPeerScorer_PeerScorerManager_loop(t *testing.T) {
 			done <- struct{}{}
 		}()
 		ticker := time.NewTicker(50 * time.Millisecond)
+		defer ticker.Stop()
 		for {
 			select {
 			case <-ticker.C:

beacon-chain/powchain/service.go

@@ -442,6 +442,7 @@ func (s *Service) waitForConnection() {
 		logCounter++
 	}
 	ticker := time.NewTicker(backOffPeriod)
+	defer ticker.Stop()
 	for {
 		select {
 		case <-ticker.C:
@@ -460,12 +461,10 @@ func (s *Service) waitForConnection() {
 				log.WithFields(logrus.Fields{
 					"endpoint": s.httpEndpoint,
 				}).Info("Connected to eth1 proof-of-work chain")
-				ticker.Stop()
 				return
 			}
 			log.Debug("Eth1 node is currently syncing")
 		case <-s.ctx.Done():
-			ticker.Stop()
 			log.Debug("Received cancelled context,closing existing powchain service")
 			return
 		}

beacon-chain/sync/initial-sync/blocks_fetcher.go

@@ -179,12 +179,12 @@ func (f *blocksFetcher) loop() {
 	// Periodically remove stale peer locks.
 	go func() {
 		ticker := time.NewTicker(peerLocksPollingInterval)
+		defer ticker.Stop()
 		for {
 			select {
 			case <-ticker.C:
 				f.removeStalePeerLocks(peerLockMaxAge)
 			case <-f.ctx.Done():
-				ticker.Stop()
 				return
 			}
 		}
@@ -338,9 +338,9 @@ func (f *blocksFetcher) requestBlocks(
 	if f.rateLimiter.Remaining(pid.String()) < int64(req.Count) {
 		log.WithField("peer", pid).Debug("Slowing down for rate limit")
 		timer := time.NewTimer(f.rateLimiter.TillEmpty(pid.String()))
+		defer timer.Stop()
 		select {
 		case <-f.ctx.Done():
-			timer.Stop()
 			return nil, errFetcherCtxIsDone
 		case <-timer.C:
 			// Peer has gathered enough capacity to be polled again.

beacon-chain/sync/initial-sync/blocks_queue.go

@@ -169,6 +169,7 @@ func (q *blocksQueue) loop() {
 	}
 
 	ticker := time.NewTicker(pollingInterval)
+	defer ticker.Stop()
 	for {
 		// Check highest expected slot when we approach chain's head slot.
 		if q.headFetcher.HeadSlot() >= q.highestExpectedSlot {
@@ -248,7 +249,6 @@ func (q *blocksQueue) loop() {
 			}
 		case <-q.ctx.Done():
 			log.Debug("Context closed, exiting goroutine (blocks queue)")
-			ticker.Stop()
 			return
 		}
 	}

shared/fileutil/fileutil.go

@@ -8,8 +8,8 @@ import (
 	"path/filepath"
 	"strings"
 
-	log "github.com/sirupsen/logrus"
 	"github.com/pkg/errors"
+	log "github.com/sirupsen/logrus"
 )
 
 // ExpandPath given a string which may be a relative path.

slasher/beaconclient/chain_data.go

@@ -60,6 +60,7 @@ func (bs *Service) querySyncStatus(ctx context.Context) {
 		return
 	}
 	ticker := time.NewTicker(syncStatusPollingInterval)
+	defer ticker.Stop()
 	log.Info("Waiting for beacon node to be fully synced...")
 	for {
 		select {

slasher/beaconclient/receivers.go

@@ -149,6 +149,7 @@ func (bs *Service) collectReceivedAttestations(ctx context.Context) {
 	var atts []*ethpb.IndexedAttestation
 	halfSlot := slotutil.DivideSlotBy(2 /* 1/2 slot duration */)
 	ticker := time.NewTicker(halfSlot)
+	defer ticker.Stop()
 	for {
 		select {
 		case <-ticker.C:
@@ -185,6 +186,7 @@ func (bs *Service) collectReceivedAttestations(ctx context.Context) {
 
 func (bs *Service) restartBeaconConnection(ctx context.Context) error {
 	ticker := time.NewTicker(reconnectPeriod)
+	defer ticker.Stop()
 	for {
 		select {
 		case <-ticker.C:
@@ -203,12 +205,10 @@ func (bs *Service) restartBeaconConnection(ctx context.Context) error {
 				continue
 			}
 			log.Info("Beacon node is fully synced")
-
 			return nil
 		case <-ctx.Done():
 			log.Debug("Context closed, exiting reconnect routine")
 			return errors.New("context closed, no longer attempting to restart stream")
 		}
 	}
-
 }

validator/client/validator.go

@@ -216,6 +216,7 @@ func (v *validator) SlasherReady(ctx context.Context) error {
 			return nil
 		}
 		ticker := time.NewTicker(reconnectPeriod)
+		defer ticker.Stop()
 		for {
 			select {
 			case <-ticker.C: