Fixes after review.

storage/local/persistence.go

@@ -482,7 +482,7 @@ func (p *persistence) loadChunkDescs(fp clientmodel.Fingerprint, beforeTime clie
 //
 // (4.4) The varint-encoded persistWatermark. (Missing in v1.)
 //
-// (4.5) The modification time of the series file as nanoceconds elapsed since
+// (4.5) The modification time of the series file as nanoseconds elapsed since
 // January 1, 1970 UTC. -1 if the modification time is unknown or no series file
 // exists yet. (Missing in v1.)
 //
@@ -1235,12 +1235,12 @@ func (p *persistence) openChunkFileForWriting(fp clientmodel.Fingerprint) (*os.F
 	// would still be detected.
 }
 
-// closeChunkFile first sync's the provided file if mandated so by the sync
+// closeChunkFile first syncs the provided file if mandated so by the sync
 // strategy. Then it closes the file. Errors are logged.
 func (p *persistence) closeChunkFile(f *os.File) {
 	if p.shouldSync() {
 		if err := f.Sync(); err != nil {
-			glog.Error("Error sync'ing file:", err)
+			glog.Error("Error syncing file:", err)
 		}
 	}
 	if err := f.Close(); err != nil {

storage/local/storage.go

@@ -73,8 +73,8 @@ const (
 	Adaptive
 )
 
-// A syncStrategy is a function that returns if series files should be sync'd or
-// not. It does not need to be goroutine safe.
+// A syncStrategy is a function that returns whether series files should be
+// synced or not. It does not need to be goroutine safe.
 type syncStrategy func() bool
 
 type memorySeriesStorage struct {
@@ -935,16 +935,21 @@ func (s *memorySeriesStorage) incNumChunksToPersist(by int) {
 
 // isDegraded returns whether the storage is in "graceful degradation mode",
 // which is the case if the number of chunks waiting for persistence has reached
-// a percentage of maxChunksToPersist that exceepds
+// a percentage of maxChunksToPersist that exceeds
 // percentChunksToPersistForDegradation. The method is not goroutine safe (but
 // only ever called from the goroutine dealing with series maintenance).
 // Changes of degradation mode are logged.
 func (s *memorySeriesStorage) isDegraded() bool {
 	nowDegraded := s.getNumChunksToPersist() > s.maxChunksToPersist*percentChunksToPersistForDegradation/100
 	if s.degraded && !nowDegraded {
-		glog.Warning("Storage has left graceful degradation mode.")
+		glog.Warning("Storage has left graceful degradation mode. Things are back to normal.")
 	} else if !s.degraded && nowDegraded {
-		glog.Warning("%d chunks waiting for persistence (allowed maximum %d). Storage is now in graceful degradation mode. Series files are not sync'd anymore. Checkpoints will not be performed more often then every %v.", s.getNumChunksToPersist, s.maxChunksToPersist, s.checkpointInterval)
+		glog.Warningf(
+			"%d chunks waiting for persistence (%d%% of the allowed maximum %d). Storage is now in graceful degradation mode. Series files are not synced anymore if following the adaptive strategy. Checkpoints are not performed more often than every %v.",
+			s.getNumChunksToPersist(),
+			s.getNumChunksToPersist()*100/s.maxChunksToPersist,
+			s.maxChunksToPersist,
+			s.checkpointInterval)
 	}
 	s.degraded = nowDegraded
 	return s.degraded