diff --git a/pkg/block/indexheader/lazy_binary_reader.go b/pkg/block/indexheader/lazy_binary_reader.go
index 8820113991c..ea2c4291505 100644
--- a/pkg/block/indexheader/lazy_binary_reader.go
+++ b/pkg/block/indexheader/lazy_binary_reader.go
@@ -138,7 +138,7 @@ func (r *LazyBinaryReader) Close() error {
 	}
 
 	// Unload without checking if idle.
-	return r.unload(0)
+	return r.unloadIfIdleSince(0)
 }
 
 // IndexVersion implements Reader.
@@ -250,9 +250,9 @@ func (r *LazyBinaryReader) load() error {
 	return nil
 }
 
-// unload closes underlying BinaryReader if the reader is idle since idleSince time (as unix nano). If idleSince is 0,
+// unloadIfIdleSince closes underlying BinaryReader if the reader is idle since given time (as unix nano). If idleSince is 0,
 // the check on the last usage is skipped. Calling this function on a already unloaded reader is a no-op.
-func (r *LazyBinaryReader) unload(idleSince int64) error {
+func (r *LazyBinaryReader) unloadIfIdleSince(ts int64) error {
 	r.readerMx.Lock()
 	defer r.readerMx.Unlock()
 
@@ -261,8 +261,8 @@ func (r *LazyBinaryReader) unload(idleSince int64) error {
 		return nil
 	}
 
-	// Do not unload if not idle.
-	if idleSince > 0 && r.usedAt.Load() > idleSince {
+	// Do not unloadIfIdleSince if not idle.
+	if ts > 0 && r.usedAt.Load() > ts {
 		return errNotIdle
 	}
 
@@ -284,9 +284,9 @@ func (r *LazyBinaryReader) isLoaded() bool {
 	return r.reader != nil
 }
 
-// isIdle returns true if the reader is idle since idleSince time (as unix nano).
-func (r *LazyBinaryReader) isIdle(idleSince int64) bool {
-	if r.usedAt.Load() > idleSince {
+// isIdleSince returns true if the reader is idle since given time (as unix nano).
+func (r *LazyBinaryReader) isIdleSince(ts int64) bool {
+	if r.usedAt.Load() > ts {
 		return false
 	}
 
diff --git a/pkg/block/indexheader/lazy_binary_reader_test.go b/pkg/block/indexheader/lazy_binary_reader_test.go
index b966bb8fbdc..0b130199b65 100644
--- a/pkg/block/indexheader/lazy_binary_reader_test.go
+++ b/pkg/block/indexheader/lazy_binary_reader_test.go
@@ -204,14 +204,14 @@ func TestLazyBinaryReader_unload_ShouldReturnErrorIfNotIdle(t *testing.T) {
 	testutil.Equals(t, float64(0), promtestutil.ToFloat64(m.unloadFailedCount))
 
 	// Try to unload but not idle since enough time.
-	testutil.Equals(t, errNotIdle, r.unload(time.Now().Add(-time.Minute).UnixNano()))
+	testutil.Equals(t, errNotIdle, r.unloadIfIdleSince(time.Now().Add(-time.Minute).UnixNano()))
 	testutil.Equals(t, float64(1), promtestutil.ToFloat64(m.loadCount))
 	testutil.Equals(t, float64(0), promtestutil.ToFloat64(m.loadFailedCount))
 	testutil.Equals(t, float64(0), promtestutil.ToFloat64(m.unloadCount))
 	testutil.Equals(t, float64(0), promtestutil.ToFloat64(m.unloadFailedCount))
 
 	// Try to unload and idle since enough time.
-	testutil.Ok(t, r.unload(time.Now().UnixNano()))
+	testutil.Ok(t, r.unloadIfIdleSince(time.Now().UnixNano()))
 	testutil.Equals(t, float64(1), promtestutil.ToFloat64(m.loadCount))
 	testutil.Equals(t, float64(0), promtestutil.ToFloat64(m.loadFailedCount))
 	testutil.Equals(t, float64(1), promtestutil.ToFloat64(m.unloadCount))
diff --git a/pkg/block/indexheader/reader_pool.go b/pkg/block/indexheader/reader_pool.go
index 9e1507efcc3..5e4da5d5f8a 100644
--- a/pkg/block/indexheader/reader_pool.go
+++ b/pkg/block/indexheader/reader_pool.go
@@ -101,20 +101,20 @@ func (p *ReaderPool) Close() {
 func (p *ReaderPool) closeIdleReaders() {
 	idleSince := time.Now().Add(-p.lazyReaderIdleTimeout).UnixNano()
 
-	for _, r := range p.getIdleReaders(idleSince) {
-		if err := r.unload(idleSince); err != nil && !errors.Is(err, errNotIdle) {
+	for _, r := range p.getIdleReadersSince(idleSince) {
+		if err := r.unloadIfIdleSince(idleSince); err != nil && !errors.Is(err, errNotIdle) {
 			level.Warn(p.logger).Log("msg", "failed to close idle index-header reader", "err", err)
 		}
 	}
 }
 
-func (p *ReaderPool) getIdleReaders(idleSince int64) []*LazyBinaryReader {
+func (p *ReaderPool) getIdleReadersSince(ts int64) []*LazyBinaryReader {
 	p.lazyReadersMx.Lock()
 	defer p.lazyReadersMx.Unlock()
 
 	var idle []*LazyBinaryReader
 	for r := range p.lazyReaders {
-		if r.isIdle(idleSince) {
+		if r.isIdleSince(ts) {
 			idle = append(idle, r)
 		}
 	}