cache heads

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

2 files changed, 3 insertions, 3 deletions

diff --git a/src/api/peers.rs b/src/api/peers.rs
index 7caaaf3..919f187 100644
--- a/src/api/peers.rs
+++ b/src/api/peers.rs
@@ -182,7 +182,7 @@ pub(crate) async fn list_peers(
     }
 
     peers.sort_by(|a, b| a.public_key.cmp(&b.public_key));
-    let local_heads = state.doc.write().await.doc.get_heads().len();
+    let local_heads = state.doc.read().await.heads().len();
     Ok(Json(PeerListResponse {
         local_alias: state.alias.clone(),
         local_epoch: local_epoch.into(),
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();