make iter_historic_layers return references

pageserver/src/tenant/layer_map.rs

@@ -543,7 +543,7 @@ impl LayerMap {
         true
     }
 
-    pub fn iter_historic_layers(&self) -> impl '_ + Iterator<Item = Arc<PersistentLayerDesc>> {
+    pub fn iter_historic_layers(&self) -> impl '_ + Iterator<Item = &Arc<PersistentLayerDesc>> {
         self.historic.iter()
     }
 

pageserver/src/tenant/layer_map/historic_layer_coverage.rs

@@ -499,14 +499,14 @@ impl<Value: Clone> BufferedHistoricLayerCoverage<Value> {
     }
 
     /// Iterate all the layers
-    pub fn iter(&self) -> impl '_ + Iterator<Item = Value> {
+    pub fn iter(&self) -> impl '_ + Iterator<Item = &Value> {
         // NOTE we can actually perform this without rebuilding,
         //      but it's not necessary for now.
         if !self.buffer.is_empty() {
             panic!("rebuild pls")
         }
 
-        self.layers.values().cloned()
+        self.layers.values()
     }
 
     /// Return a reference to a queryable map, assuming all updates

pageserver/src/tenant/timeline/compaction.rs

@@ -1596,7 +1596,7 @@ impl CompactionJobExecutor for TimelineAdaptor {
             .filter(|l| {
                 overlaps_with(&l.lsn_range, lsn_range) && overlaps_with(&l.key_range, key_range)
             })
-            .map(OwnArc)
+            .map(|l| OwnArc(l.clone()))
             .collect();
         Ok(result)
     }