cache heads

To reduce the number of write locks, heads are now cached.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/api/stats.rs b/src/api/stats.rs
index bc925ff..838cc0f 100644
--- a/src/api/stats.rs
+++ b/src/api/stats.rs
@@ -134,8 +134,8 @@ async fn collect(state: &AppState) -> StatsResponse {
     let node = state.stats.snapshot();
 
     let (heads, tier) = {
-        let mut replica = state.doc.write().await;
-        let heads = replica.doc.get_heads().len();
+        let replica = state.doc.read().await;
+        let heads = replica.heads().len();
         (heads, members::tier(&replica.doc, state.local_id()))
     };
     let saved = state.stats.saved_size();