diff --git a/src/client_server/directory.rs b/src/client_server/directory.rs
index 7cab1a7..589aacd 100644
--- a/src/client_server/directory.rs
+++ b/src/client_server/directory.rs
@@ -1,3 +1,5 @@
+use std::convert::TryInto;
+
 use crate::{database::DatabaseGuard, ConduitResult, Database, Error, Result, Ruma};
 use ruma::{
     api::{
@@ -21,7 +23,7 @@ use ruma::{
     serde::Raw,
     ServerName, UInt,
 };
-use tracing::info;
+use tracing::{info, warn};
 
 #[cfg(feature = "conduit_bin")]
 use rocket::{get, post, put};
@@ -234,7 +236,15 @@ pub async fn get_public_rooms_filtered_helper(
                             .name
                             .map(|n| n.to_owned().into()))
                         })?,
-                    num_joined_members: (db.rooms.room_members(&room_id).count() as u32).into(),
+                    num_joined_members: db
+                        .rooms
+                        .room_joined_count(&room_id)?
+                        .unwrap_or_else(|| {
+                            warn!("Room {} has no member count", room_id);
+                            0
+                        })
+                        .try_into()
+                        .expect("user count should not be that big"),
                     topic: db
                         .rooms
                         .room_state_get(&room_id, &EventType::RoomTopic, "")?
diff --git a/src/database.rs b/src/database.rs
index 4f3d332..2e7e60c 100644
--- a/src/database.rs
+++ b/src/database.rs
@@ -24,10 +24,11 @@ use rocket::{
     request::{FromRequest, Request},
     Shutdown, State,
 };
-use ruma::{DeviceId, ServerName, UserId};
+use ruma::{DeviceId, RoomId, ServerName, UserId};
 use serde::{de::IgnoredAny, Deserialize};
 use std::{
     collections::{BTreeMap, HashMap},
+    convert::TryFrom,
     fs::{self, remove_dir_all},
     io::Write,
     ops::Deref,
@@ -252,6 +253,7 @@ impl Database {
                 serverroomids: builder.open_tree("serverroomids")?,
                 userroomid_joined: builder.open_tree("userroomid_joined")?,
                 roomuserid_joined: builder.open_tree("roomuserid_joined")?,
+                roomid_joinedcount: builder.open_tree("roomid_joinedcount")?,
                 roomuseroncejoinedids: builder.open_tree("roomuseroncejoinedids")?,
                 userroomid_invitestate: builder.open_tree("userroomid_invitestate")?,
                 roomuserid_invitecount: builder.open_tree("roomuserid_invitecount")?,
@@ -271,8 +273,8 @@ impl Database {
 
                 eventid_outlierpdu: builder.open_tree("eventid_outlierpdu")?,
                 referencedevents: builder.open_tree("referencedevents")?,
-                pdu_cache: Mutex::new(LruCache::new(1_000_000)),
-                auth_chain_cache: Mutex::new(LruCache::new(1_000_000)),
+                pdu_cache: Mutex::new(LruCache::new(0)),
+                auth_chain_cache: Mutex::new(LruCache::new(0)),
             },
             account_data: account_data::AccountData {
                 roomuserdataid_accountdata: builder.open_tree("roomuserdataid_accountdata")?,
@@ -423,6 +425,20 @@ impl Database {
 
                 println!("Migration: 4 -> 5 finished");
             }
+
+            if db.globals.database_version()? < 9 { // TODO update to 6
+                // Set room member count
+                for (roomid, _) in db.rooms.roomid_shortstatehash.iter() {
+                    let room_id =
+                        RoomId::try_from(utils::string_from_bytes(&roomid).unwrap()).unwrap();
+
+                    db.rooms.update_joined_count(&room_id)?;
+                }
+
+                db.globals.bump_database_version(6)?;
+
+                println!("Migration: 5 -> 6 finished");
+            }
         }
 
         let guard = db.read().await;
diff --git a/src/database/abstraction/sled.rs b/src/database/abstraction/sled.rs
index d99ce26..35ba1b2 100644
--- a/src/database/abstraction/sled.rs
+++ b/src/database/abstraction/sled.rs
@@ -39,12 +39,21 @@ impl Tree for SledEngineTree {
         Ok(())
     }
 
+    #[tracing::instrument(skip(self, iter))]
+    fn insert_batch<'a>(&self, iter: &mut dyn Iterator<Item = (Vec<u8>, Vec<u8>)>) -> Result<()> {
+        for (key, value) in iter {
+            self.0.insert(key, value)?;
+        }
+
+        Ok(())
+    }
+
     fn remove(&self, key: &[u8]) -> Result<()> {
         self.0.remove(key)?;
         Ok(())
     }
 
-    fn iter<'a>(&'a self) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + Send + 'a> {
+    fn iter<'a>(&'a self) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + 'a> {
         Box::new(
             self.0
                 .iter()
@@ -62,7 +71,7 @@ impl Tree for SledEngineTree {
         &self,
         from: &[u8],
         backwards: bool,
-    ) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + Send> {
+    ) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)>> {
         let iter = if backwards {
             self.0.range(..=from)
         } else {
@@ -95,7 +104,7 @@ impl Tree for SledEngineTree {
     fn scan_prefix<'a>(
         &'a self,
         prefix: Vec<u8>,
-    ) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + Send + 'a> {
+    ) -> Box<dyn Iterator<Item = (Vec<u8>, Vec<u8>)> + 'a> {
         let iter = self
             .0
             .scan_prefix(prefix)
diff --git a/src/database/abstraction/sqlite.rs b/src/database/abstraction/sqlite.rs
index 72fb5f7..0dbb261 100644
--- a/src/database/abstraction/sqlite.rs
+++ b/src/database/abstraction/sqlite.rs
@@ -55,7 +55,6 @@ impl Engine {
         conn.pragma_update(Some(Main), "journal_mode", &"WAL")?;
         conn.pragma_update(Some(Main), "synchronous", &"NORMAL")?;
         conn.pragma_update(Some(Main), "cache_size", &(-i64::from(cache_size_kb)))?;
-        conn.pragma_update(Some(Main), "wal_autocheckpoint", &0)?;
 
         Ok(conn)
     }
diff --git a/src/database/rooms.rs b/src/database/rooms.rs
index 549aa8c..10a6215 100644
--- a/src/database/rooms.rs
+++ b/src/database/rooms.rs
@@ -55,6 +55,7 @@ pub struct Rooms {
 
     pub(super) userroomid_joined: Arc<dyn Tree>,
     pub(super) roomuserid_joined: Arc<dyn Tree>,
+    pub(super) roomid_joinedcount: Arc<dyn Tree>,
     pub(super) roomuseroncejoinedids: Arc<dyn Tree>,
     pub(super) userroomid_invitestate: Arc<dyn Tree>, // InviteState = Vec<Raw<Pdu>>
     pub(super) roomuserid_invitecount: Arc<dyn Tree>, // InviteCount = Count
@@ -1906,9 +1907,18 @@ impl Rooms {
             _ => {}
         }
 
+        self.update_joined_count(room_id)?;
+
         Ok(())
     }
 
+    pub fn update_joined_count(&self, room_id: &RoomId) -> Result<()> {
+        self.roomid_joinedcount.insert(
+            room_id.as_bytes(),
+            &(self.room_members(&room_id).count() as u64).to_be_bytes(),
+        )
+    }
+
     pub async fn leave_room(
         &self,
         user_id: &UserId,
@@ -2370,6 +2380,17 @@ impl Rooms {
         })
     }
 
+    pub fn room_joined_count(&self, room_id: &RoomId) -> Result<Option<u64>> {
+        Ok(self
+            .roomid_joinedcount
+            .get(room_id.as_bytes())?
+            .map(|b| {
+                utils::u64_from_bytes(&b)
+                    .map_err(|_| Error::bad_database("Invalid joinedcount in db."))
+            })
+            .transpose()?)
+    }
+
     /// Returns an iterator over all User IDs who ever joined a room.
     #[tracing::instrument(skip(self))]
     pub fn room_useroncejoined<'a>(
diff --git a/src/server_server.rs b/src/server_server.rs
index 0e595d4..4255f12 100644
--- a/src/server_server.rs
+++ b/src/server_server.rs
@@ -1,6 +1,6 @@
 use crate::{
     client_server::{self, claim_keys_helper, get_keys_helper},
-    database::{abstraction::sqlite::MILLI, DatabaseGuard},
+    database::{DatabaseGuard},
     utils, ConduitResult, Database, Error, PduEvent, Result, Ruma,
 };
 use get_profile_information::v1::ProfileField;
@@ -1736,20 +1736,11 @@ fn get_auth_chain(starting_events: Vec<EventId>, db: &Database) -> Result<HashSe
             full_auth_chain.extend(cached.iter().cloned());
         } else {
             drop(cache);
-            let start = Instant::now();
             let auth_chain = get_auth_chain_recursive(&event_id, HashSet::new(), db)?;
-            let elapsed = start.elapsed();
-            if elapsed > MILLI {
-                println!("auth chain for {} took {:?}", &event_id, elapsed)
-            }
-
             cache = db.rooms.auth_chain_cache();
-
             cache.insert(vec![event_id.clone()], auth_chain.clone());
-
             full_auth_chain.extend(auth_chain);
         };
-
     }
 
     cache.insert(starting_events, full_auth_chain.clone());