diff --git a/src/service/migrations.rs b/src/service/migrations.rs
index 747da65ac..0a5881063 100644
--- a/src/service/migrations.rs
+++ b/src/service/migrations.rs
@@ -2,6 +2,8 @@
 	cmp,
 	collections::{BTreeMap, HashMap},
 	future::ready,
+	sync::Arc,
+	time::Instant,
 };
 
 use conduwuit::{
@@ -15,7 +17,7 @@
 	},
 	warn,
 };
-use database::Json;
+use database::{Database, Json};
 use futures::{FutureExt, StreamExt, TryStreamExt};
 use itertools::Itertools;
 use ruma::{
@@ -30,7 +32,7 @@
 };
 use serde_json::value::to_raw_value;
 
-use crate::{Services, media, rooms::short::ShortStateHash};
+use crate::{Services, media, rooms, rooms::short::ShortStateHash};
 
 /// The current schema version.
 /// - If database is opened at greater version we reject with error. The
@@ -125,7 +127,7 @@ async fn migrate(services: &Services) -> Result<()> {
 			.map_err(|e| err!("Failed to run SHA256 media migration: {e}"))?;
 	} else if config.media_startup_check {
 		info!("Starting media startup integrity check.");
-		let now = std::time::Instant::now();
+		let now = Instant::now();
 		media::migrations::checkup_sha256_media(services)
 			.await
 			.map_err(|e| err!("Failed to verify media integrity: {e}"))?;
@@ -263,9 +265,11 @@ async fn migrate(services: &Services) -> Result<()> {
 	}
 
 	if db["global"].get(UNEMBED_UNSIGNED_INFO).await.is_not_found() {
-		unembed_unsigned_info(services)
-			.await
-			.map_err(|e| err!("Failed to run 'unembed_unsigned_info' migration: {e:?}"))?;
+		services.server.runtime().spawn(unembed_unsigned_info(
+			services.db.clone(),
+			services.rooms.metadata.clone(),
+			services.rooms.timeline.clone(),
+		));
 	}
 
 	assert_eq!(
@@ -916,12 +920,25 @@ async fn obliterate_roomsynctoken_shortstatehash_with_extreme_prejudice(
 }
 
 const UNEMBED_UNSIGNED_INFO: &str = "unembed_unsigned_info";
-async fn unembed_unsigned_info(services: &Services) -> Result {
+#[tracing::instrument(name = "unembed_unsigned_info", skip_all)]
+async fn unembed_unsigned_info(
+	db: Arc<Database>,
+	metadata: Arc<rooms::metadata::Service>,
+	timeline: Arc<rooms::timeline::Service>,
+) -> Result {
 	type Map = BTreeMap<String, Box<serde_json::value::RawValue>>;
+	info!(
+		"Starting background migration. This may take a long time, and may cause your server to \
+		 lag. Please avoid restarting until the migration is complete."
+	);
 
-	let mut all_rooms = services.rooms.metadata.iter_ids();
+	let start = Instant::now();
+	let mut total_migrated = 0_usize;
+	let mut all_rooms = metadata.iter_ids();
 	while let Some(room_id) = all_rooms.next().await {
-		let mut pdus = std::pin::pin!(services.rooms.timeline.all_pdus(&room_id));
+		info!("Migrating PDUs in {room_id}");
+		let mut pdus = std::pin::pin!(timeline.all_pdus(&room_id));
+		let mut migrated = 0_usize;
 		while let Some((_, pdu)) = pdus.next().await {
 			let mut pdu = pdu.clone();
 			let mut unsigned: Map = pdu
@@ -951,20 +968,22 @@ async fn unembed_unsigned_info(services: &Services) -> Result {
 				}
 			}
 			pdu.unsigned = Some(to_raw_value(&unsigned).expect("unsigned must be valid JSON"));
-			let pdu_id = services
-				.rooms
-				.timeline
+			let pdu_id = timeline
 				.get_pdu_id(pdu.event_id())
 				.await
 				.expect("PDU must have an id");
-			services
-				.rooms
-				.timeline
+			timeline
 				.replace_pdu(&pdu_id, &to_canonical_object(pdu).expect("PDU must be valid JSON"))
 				.await
 				.expect("must be able to replace PDU after migrating unsigned data");
+			migrated = migrated.saturating_add(1);
 		}
+		total_migrated = total_migrated.saturating_add(migrated);
+		info!(elapsed=?start.elapsed(), "Migrated {migrated} PDUs in {room_id}");
 	}
 
+	db["global"].insert(UNEMBED_UNSIGNED_INFO, []);
+	info!(elapsed=?start.elapsed(), total_migrated_pdus=total_migrated, "Finished migration.");
+
 	Ok(())
 }