Optimize reference graph container value type for topological_sort.

Optimize initial container capacity estimates.

Signed-off-by: Jason Volk <jason@zemos.net>

src/service/rooms/event_handler/fetch_prev.rs

@@ -1,7 +1,4 @@
-use std::{
-	collections::{HashMap, HashSet},
-	iter::once,
-};
+use std::{collections::HashMap, iter::once};
 
 use futures::{FutureExt, StreamExt, stream::FuturesOrdered};
 use ruma::{
@@ -50,7 +47,7 @@ where
 	while let Some((prev_event_id, mut outlier)) = todo_outlier_stack.next().await {
 		let Some((pdu, mut json_opt)) = outlier.pop() else {
 			// Fetch and handle failed
-			graph.insert(prev_event_id.clone(), HashSet::new());
+			graph.insert(prev_event_id.clone(), Default::default());
 			continue;
 		};
 
@@ -59,7 +56,7 @@ where
 		let limit = self.services.server.config.max_fetch_prev_events;
 		if amount > limit {
 			debug_warn!(?limit, "Max prev event limit reached!");
-			graph.insert(prev_event_id.clone(), HashSet::new());
+			graph.insert(prev_event_id.clone(), Default::default());
 			continue;
 		}
 
@@ -74,7 +71,7 @@ where
 
 		let Some(json) = json_opt else {
 			// Get json failed, so this was not fetched over federation
-			graph.insert(prev_event_id.clone(), HashSet::new());
+			graph.insert(prev_event_id.clone(), Default::default());
 			continue;
 		};
 
@@ -104,7 +101,7 @@ where
 			);
 		} else {
 			// Time based check failed
-			graph.insert(prev_event_id.clone(), HashSet::new());
+			graph.insert(prev_event_id.clone(), Default::default());
 		}
 
 		eventid_info.insert(prev_event_id.clone(), (pdu, json));

src/service/rooms/event_handler/mod.rs

@@ -110,11 +110,24 @@ fn is_backed_off(&self, event_id: &EventId, range: Range<Duration>) -> bool {
 }
 
 #[implement(Service)]
+#[tracing::instrument(
+	name = "exists",
+	level = "trace",
+	ret(level = "trace"),
+	skip_all,
+	fields(%event_id)
+)]
 async fn event_exists(&self, event_id: &EventId) -> bool {
 	self.services.timeline.pdu_exists(event_id).await
 }
 
 #[implement(Service)]
+#[tracing::instrument(
+	name = "fetch",
+	level = "trace",
+	skip_all,
+	fields(%event_id)
+)]
 async fn event_fetch(&self, event_id: &EventId) -> Result<PduEvent> {
 	self.services.timeline.get_pdu(event_id).await
 }

src/service/rooms/event_handler/resolve_state.rs

@@ -103,15 +103,10 @@ pub async fn resolve_state(
 }
 
 #[implement(super::Service)]
-#[tracing::instrument(
-	name = "resolve",
-	level = "debug",
-	skip_all,
-	fields(%room_id),
-)]
+#[tracing::instrument(name = "resolve", level = "debug", skip_all)]
 pub(super) async fn state_resolution<StateSets, AuthSets>(
 	&self,
-	room_id: &RoomId,
+	_room_id: &RoomId,
 	room_version: &RoomVersionId,
 	state_sets: StateSets,
 	auth_chains: AuthSets,

src/service/rooms/event_handler/upgrade_outlier_pdu.rs

@@ -22,8 +22,8 @@ use crate::rooms::{
 #[tracing::instrument(
 	name = "upgrade",
 	level = "debug",
-	skip_all,
-	ret(level = "debug")
+	ret(level = "debug"),
+	skip_all
 )]
 pub(super) async fn upgrade_outlier_to_timeline_pdu(
 	&self,