feat(sqlite): Run VACUUM operation after removing a room

A room can be associated to a lot of data, depending on the number of members in the room.
So freeing space on the filesystem should be worth it in some cases.

An (extreme) example: I have a test account that is in ~60 rooms, a few of those big public rooms, including Matrix HQ. The size of the matrix-sdk-state.sqlite3 file is 542 MB. Using this PR and leaving, then forgetting Matrix HQ brings the DB down to 255 MB.

crates/matrix-sdk-sqlite/CHANGELOG.md

@@ -10,6 +10,8 @@ All notable changes to this project will be documented in this file.
 
 - Implement the new method of `EventCacheStoreMedia` for `SqliteEventCacheStore`.
   ([#4603](https://github.com/matrix-org/matrix-rust-sdk/pull/4603))
+- Defragment an sqlite state store after removing a room.
+  ([#4651](https://github.com/matrix-org/matrix-rust-sdk/pull/4651))
 
 ## [0.10.0] - 2025-02-04
 

crates/matrix-sdk-sqlite/src/event_cache_store.rs

@@ -36,8 +36,6 @@ use matrix_sdk_store_encryption::StoreCipher;
 use ruma::{time::SystemTime, MilliSecondsSinceUnixEpoch, MxcUri, RoomId};
 use rusqlite::{params_from_iter, OptionalExtension, Transaction, TransactionBehavior};
 use tokio::fs;
-#[cfg(not(test))]
-use tracing::warn;
 use tracing::{debug, trace};
 
 use crate::{
@@ -959,19 +957,10 @@ impl EventCacheStoreMedia for SqliteEventCacheStore {
             })
             .await?;
 
-        // If we removed media, use the VACUUM command to defragment the
-        // database and free space on the filesystem.
+        // If we removed media, defragment the database and free space on the
+        // filesystem.
         if removed {
-            if let Err(error) = conn.execute("VACUUM", ()).await {
-                // Since this is an optimisation step, do not propagate the error
-                // but log it.
-                #[cfg(not(test))]
-                warn!("Failed to vacuum database: {error}");
-
-                // We want to know if there is an error with this step during tests.
-                #[cfg(test)]
-                return Err(error.into());
-            }
+            conn.vacuum().await?;
         }
 
         Ok(())

crates/matrix-sdk-sqlite/src/state_store.rs

@@ -336,7 +336,7 @@ impl SqliteStateStore {
             // Defragment the DB and optimize its size on the filesystem.
             // This should have been run in the migration for version 7, to reduce the size
             // of the DB as we removed the media cache.
-            conn.execute_batch("VACUUM").await?;
+            conn.vacuum().await?;
             conn.set_kv("version", vec![12]).await?;
         }
 
@@ -1739,40 +1739,42 @@ impl StateStore for SqliteStateStore {
         let this = self.clone();
         let room_id = room_id.to_owned();
 
-        self.acquire()
-            .await?
-            .with_transaction(move |txn| {
-                let room_info_room_id = this.encode_key(keys::ROOM_INFO, &room_id);
-                txn.remove_room_info(&room_info_room_id)?;
+        let conn = self.acquire().await?;
 
-                let state_event_room_id = this.encode_key(keys::STATE_EVENT, &room_id);
-                txn.remove_room_state_events(&state_event_room_id, None)?;
+        conn.with_transaction(move |txn| -> Result<()> {
+            let room_info_room_id = this.encode_key(keys::ROOM_INFO, &room_id);
+            txn.remove_room_info(&room_info_room_id)?;
 
-                let member_room_id = this.encode_key(keys::MEMBER, &room_id);
-                txn.remove_room_members(&member_room_id, None)?;
+            let state_event_room_id = this.encode_key(keys::STATE_EVENT, &room_id);
+            txn.remove_room_state_events(&state_event_room_id, None)?;
 
-                let profile_room_id = this.encode_key(keys::PROFILE, &room_id);
-                txn.remove_room_profiles(&profile_room_id)?;
+            let member_room_id = this.encode_key(keys::MEMBER, &room_id);
+            txn.remove_room_members(&member_room_id, None)?;
 
-                let room_account_data_room_id = this.encode_key(keys::ROOM_ACCOUNT_DATA, &room_id);
-                txn.remove_room_account_data(&room_account_data_room_id)?;
+            let profile_room_id = this.encode_key(keys::PROFILE, &room_id);
+            txn.remove_room_profiles(&profile_room_id)?;
 
-                let receipt_room_id = this.encode_key(keys::RECEIPT, &room_id);
-                txn.remove_room_receipts(&receipt_room_id)?;
+            let room_account_data_room_id = this.encode_key(keys::ROOM_ACCOUNT_DATA, &room_id);
+            txn.remove_room_account_data(&room_account_data_room_id)?;
 
-                let display_name_room_id = this.encode_key(keys::DISPLAY_NAME, &room_id);
-                txn.remove_room_display_names(&display_name_room_id)?;
+            let receipt_room_id = this.encode_key(keys::RECEIPT, &room_id);
+            txn.remove_room_receipts(&receipt_room_id)?;
 
-                let send_queue_room_id = this.encode_key(keys::SEND_QUEUE, &room_id);
-                txn.remove_room_send_queue(&send_queue_room_id)?;
+            let display_name_room_id = this.encode_key(keys::DISPLAY_NAME, &room_id);
+            txn.remove_room_display_names(&display_name_room_id)?;
 
-                let dependent_send_queue_room_id =
-                    this.encode_key(keys::DEPENDENTS_SEND_QUEUE, &room_id);
-                txn.remove_room_dependent_send_queue(&dependent_send_queue_room_id)?;
+            let send_queue_room_id = this.encode_key(keys::SEND_QUEUE, &room_id);
+            txn.remove_room_send_queue(&send_queue_room_id)?;
 
-                Ok(())
-            })
-            .await
+            let dependent_send_queue_room_id =
+                this.encode_key(keys::DEPENDENTS_SEND_QUEUE, &room_id);
+            txn.remove_room_dependent_send_queue(&dependent_send_queue_room_id)?;
+
+            Ok(())
+        })
+        .await?;
+
+        conn.vacuum().await
     }
 
     async fn save_send_queue_request(

crates/matrix-sdk-sqlite/src/utils.rs

@@ -136,6 +136,24 @@ pub(crate) trait SqliteAsyncConnExt {
         self.execute_batch("PRAGMA journal_size_limit = 10000000;").await.map_err(Error::from)?;
         Ok(())
     }
+
+    /// Defragment the database and free space on the filesystem.
+    ///
+    /// Only returns an error in tests, otherwise the error is only logged.
+    async fn vacuum(&self) -> Result<()> {
+        if let Err(error) = self.execute_batch("VACUUM").await {
+            // Since this is an optimisation step, do not propagate the error
+            // but log it.
+            #[cfg(not(any(test, debug_assertions)))]
+            tracing::warn!("Failed to vacuum database: {error}");
+
+            // We want to know if there is an error with this step during tests.
+            #[cfg(any(test, debug_assertions))]
+            return Err(error.into());
+        }
+
+        Ok(())
+    }
 }
 
 #[async_trait]