chore: merge 1818 nex/perf/get-missing-events

src/admin/debug/commands.rs

@@ -31,6 +31,8 @@
 };
 use tracing_subscriber::EnvFilter;
 
+use crate::PAGE_SIZE;
+
 #[derive(Clone, Copy, Eq, PartialEq)]
 enum NodeStatus {
 	Normal(bool),
@@ -1166,4 +1168,56 @@ pub(super) async fn send_test_email(&self) -> Result {
 
 		Ok(())
 	}
+
+	pub(super) async fn rooms_by_extremity_count(&self, page: Option<usize>) -> Result {
+		let page = page.unwrap_or(1);
+		// My Giant Chain:tm:
+		let mapped: HashMap<OwnedRoomId, u64> = self
+			.services
+			.rooms
+			.state
+			.all_forward_extremities()
+			.ready_fold(HashMap::new(), move |mut map, (room_id, _)| {
+				let count: u64 = map.get(&room_id).copied().unwrap_or(0);
+				map.insert(room_id, count.saturating_add(1));
+				map
+			})
+			.await
+			.into_iter()
+			.filter_map(|(room_id, count)| (count >= 2).then_some((room_id, count)))
+			.collect();
+		if mapped.is_empty() {
+			return Err!("No more rooms.");
+		}
+
+		let mut rooms = mapped.keys().collect::<Vec<_>>();
+		rooms.sort_by_key(|room_id| {
+			mapped
+				.get(*room_id)
+				.copied()
+				.expect("keys must have values")
+		});
+		rooms.reverse();
+
+		let body = rooms
+			.into_iter()
+			.stream()
+			.skip(page.saturating_sub(1).saturating_mul(PAGE_SIZE))
+			.take(PAGE_SIZE)
+			.map(|room_id| {
+				format!(
+					"{room_id}: {}",
+					mapped.get(room_id).copied().expect("keys must have values")
+				)
+			})
+			.collect::<Vec<_>>()
+			.await;
+
+		self.write_str(&format!(
+			"Rooms by extremity count ({}):\n```\n{}\n```",
+			body.len(),
+			body.join("\n")
+		))
+		.await
+	}
 }

src/admin/debug/mod.rs

@@ -245,6 +245,11 @@ pub enum DebugCommand {
 	/// Send a test email to the invoking admin's email address
 	SendTestEmail,
 
+	/// Lists room IDs by forward extremity count in descending order
+	RoomsByExtremityCount {
+		page: Option<usize>,
+	},
+
 	/// Developer test stubs
 	#[command(subcommand)]
 	#[allow(non_snake_case)]