Merge pull request #8121 from influxdata/er-drop-db

Speed up DROP DATABASE

CHANGELOG.md

@@ -21,6 +21,7 @@
 - [#7811](https://github.com/influxdata/influxdb/issues/7811): Kill query not killing query
 - [#7457](https://github.com/influxdata/influxdb/issues/7457): KILL QUERY should work during all phases of a query
 - [#8155](https://github.com/influxdata/influxdb/pull/8155): Simplify admin user check.
+- [#8118](https://github.com/influxdata/influxdb/issues/8118): Significantly improve DROP DATABASE speed.
 
 ## v1.2.2 [2017-03-14]
 

tsdb/meta.go

@@ -509,39 +509,6 @@ func (d *DatabaseIndex) dropMeasurement(name string) {
 	atomic.AddInt64(&d.stats.NumMeasurementsDropped, 1)
 }
 
-// DropSeries removes the series keys and their tags from the index.
-func (d *DatabaseIndex) DropSeries(keys []string) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-
-	var (
-		mToDelete = map[string]struct{}{}
-		nDeleted  int64
-	)
-
-	for _, k := range keys {
-		series := d.series[k]
-		if series == nil {
-			continue
-		}
-		series.measurement.DropSeries(series)
-		delete(d.series, k)
-		nDeleted++
-
-		// If there are no more series in the measurement then we'll
-		// remove it.
-		if len(series.measurement.seriesByID) == 0 {
-			mToDelete[series.measurement.Name] = struct{}{}
-		}
-	}
-
-	for mname := range mToDelete {
-		d.dropMeasurement(mname)
-	}
-	atomic.AddInt64(&d.stats.NumSeries, -nDeleted)
-	atomic.AddInt64(&d.stats.NumSeriesDropped, nDeleted)
-}
-
 // Dereference removes all references to data within b and moves them to the heap.
 func (d *DatabaseIndex) Dereference(b []byte) {
 	d.mu.RLock()

tsdb/shard.go

@@ -271,7 +271,7 @@ func (s *Shard) Open() error {
 
 		return nil
 	}(); err != nil {
-		s.close()
+		s.close(true)
 		return NewShardError(s.id, err)
 	}
 
@@ -289,14 +289,28 @@ func (s *Shard) UnloadIndex() {
 	s.index.RemoveShard(s.id)
 }
 
-// Close shuts down the shard's store.
+// Close closes the shard, removing the shard ID and any of the shard's series
+// keys from any associated indexes.
 func (s *Shard) Close() error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	return s.close()
+	return s.close(true)
 }
 
-func (s *Shard) close() error {
+// CloseFast closes the shard without cleaning up the shard ID or any of the
+// shard's series keys from the index it belongs to.
+//
+// CloseFast can be called when the entire index is being removed, e.g., when
+// the database the shard belongs to is being dropped.
+func (s *Shard) CloseFast() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.close(false)
+}
+
+// close closes the shard an removes reference to the shard from associated
+// indexes, unless clean is false.
+func (s *Shard) close(clean bool) error {
 	if s.engine == nil {
 		return nil
 	}
@@ -308,8 +322,10 @@ func (s *Shard) close() error {
 		close(s.closing)
 	}
 
-	// Don't leak our shard ID and series keys in the index
-	s.UnloadIndex()
+	if clean {
+		// Don't leak our shard ID and series keys in the index
+		s.UnloadIndex()
+	}
 
 	err := s.engine.Close()
 	if err == nil {

tsdb/store.go

@@ -402,7 +402,7 @@ func (s *Store) DeleteDatabase(name string) error {
 			return nil
 		}
 
-		return sh.Close()
+		return sh.CloseFast()
 	}); err != nil {
 		return err
 	}