diff --git a/tsdb/engine/tsm1/engine.go b/tsdb/engine/tsm1/engine.go
index f1a61baa3d..ae3c0e0d7b 100644
--- a/tsdb/engine/tsm1/engine.go
+++ b/tsdb/engine/tsm1/engine.go
@@ -339,13 +339,12 @@ func (e *Engine) enableLevelCompactions(wait bool) {
 
 	// last one to enable, start things back up
 	e.Compactor.EnableCompactions()
-	quit := make(chan struct{})
-	e.done = quit
+	e.done = make(chan struct{})
 
 	e.wg.Add(1)
 	e.mu.Unlock()
 
-	go func() { defer e.wg.Done(); e.compact(quit) }()
+	go func() { defer e.wg.Done(); e.compact() }()
 }
 
 // disableLevelCompactions will stop level compactions before returning.
@@ -417,12 +416,11 @@ func (e *Engine) enableSnapshotCompactions() {
 	}
 
 	e.Compactor.EnableSnapshots()
-	quit := make(chan struct{})
-	e.snapDone = quit
+	e.snapDone = make(chan struct{})
 	e.snapWG.Add(1)
 	e.mu.Unlock()
 
-	go func() { defer e.snapWG.Done(); e.compactCache(quit) }()
+	go func() { defer e.snapWG.Done(); e.compactCache() }()
 }
 
 func (e *Engine) disableSnapshotCompactions() {
@@ -1597,10 +1595,14 @@ func (e *Engine) writeSnapshotAndCommit(closedFiles []string, snapshot *Cache) (
 }
 
 // compactCache continually checks if the WAL cache should be written to disk.
-func (e *Engine) compactCache(quit <-chan struct{}) {
+func (e *Engine) compactCache() {
 	t := time.NewTicker(time.Second)
 	defer t.Stop()
 	for {
+		e.mu.RLock()
+		quit := e.snapDone
+		e.mu.RUnlock()
+
 		select {
 		case <-quit:
 			return
@@ -1636,11 +1638,15 @@ func (e *Engine) ShouldCompactCache(lastWriteTime time.Time) bool {
 		time.Since(lastWriteTime) > e.CacheFlushWriteColdDuration
 }
 
-func (e *Engine) compact(quit <-chan struct{}) {
+func (e *Engine) compact() {
 	t := time.NewTicker(time.Second)
 	defer t.Stop()
 
 	for {
+		e.mu.RLock()
+		quit := e.done
+		e.mu.RUnlock()
+
 		select {
 		case <-quit:
 			return
diff --git a/tsdb/engine/tsm1/engine_test.go b/tsdb/engine/tsm1/engine_test.go
index 53475c4fbc..779af49b2f 100644
--- a/tsdb/engine/tsm1/engine_test.go
+++ b/tsdb/engine/tsm1/engine_test.go
@@ -983,10 +983,14 @@ func TestIndex_SeriesIDSet(t *testing.T) {
 		// series for the gpu measurement...
 		for _, id := range ids {
 			contains := engine.SeriesIDSet().Contains(id)
-			if id < 4 && !contains {
-				return fmt.Errorf("bitmap does not contain ID: %d, but should", id)
-			} else if id >= 4 && contains {
-				return fmt.Errorf("bitmap still contains ID: %d after delete", id)
+			key, _ := engine.sfile.Series(id)
+			isGpu := bytes.Equal(key, []byte("gpu"))
+			isMem := bytes.Equal(key, []byte("mem"))
+
+			if (isGpu || isMem) && contains {
+				return fmt.Errorf("bitmap still contains ID: %d after delete: %s", id, string(key))
+			} else if !(isGpu || isMem) && !contains {
+				return fmt.Errorf("bitmap does not contain ID: %d, but should: %s", id, string(key))
 			}
 		}
 
@@ -997,10 +1001,14 @@ func TestIndex_SeriesIDSet(t *testing.T) {
 
 		for _, id := range ids {
 			contains := engine.SeriesIDSet().Contains(id)
-			if id < 4 && !contains {
-				return fmt.Errorf("[after re-open] bitmap does not contain ID: %d, but should", id)
-			} else if id >= 4 && contains {
-				return fmt.Errorf("[after re-open] bitmap still contains ID: %d after delete", id)
+			key, _ := engine.sfile.Series(id)
+			isGpu := bytes.Equal(key, []byte("gpu"))
+			isMem := bytes.Equal(key, []byte("mem"))
+
+			if (isGpu || isMem) && contains {
+				return fmt.Errorf("[after re-open] bitmap still contains ID: %d after delete: %s", id, string(key))
+			} else if !(isGpu || isMem) && !contains {
+				return fmt.Errorf("[after re-open] bitmap does not contain ID: %d, but should: %s", id, string(key))
 			}
 		}
 		return nil
diff --git a/tsdb/series_file.go b/tsdb/series_file.go
index 383608f83a..6c27cd7aeb 100644
--- a/tsdb/series_file.go
+++ b/tsdb/series_file.go
@@ -74,7 +74,6 @@ func (f *SeriesFile) Close() (err error) {
 			err = e
 		}
 	}
-	f.partitions = nil
 	return err
 }