improvement: better memory usage and admin commands to analyze it

src/service/admin/mod.rs

@@ -134,7 +134,13 @@ enum AdminCommand {
     },
 
     /// Print database memory usage statistics
-    DatabaseMemoryUsage,
+    MemoryUsage,
+
+    /// Clears all of Conduit's database caches with index smaller than the amount
+    ClearDatabaseCaches { amount: u32 },
+
+    /// Clears all of Conduit's service caches with index smaller than the amount
+    ClearServiceCaches { amount: u32 },
 
     /// Show configuration values
     ShowConfig,
@@ -531,12 +537,24 @@ impl Service {
                     None => RoomMessageEventContent::text_plain("PDU not found."),
                 }
             }
-            AdminCommand::DatabaseMemoryUsage => match services().globals.db.memory_usage() {
-                Ok(response) => RoomMessageEventContent::text_plain(response),
-                Err(e) => RoomMessageEventContent::text_plain(format!(
-                    "Failed to get database memory usage: {e}"
-                )),
-            },
+            AdminCommand::MemoryUsage => {
+                let response1 = services().memory_usage();
+                let response2 = services().globals.db.memory_usage();
+
+                RoomMessageEventContent::text_plain(format!(
+                    "Services:\n{response1}\n\nDatabase:\n{response2}"
+                ))
+            }
+            AdminCommand::ClearDatabaseCaches { amount } => {
+                services().globals.db.clear_caches(amount);
+
+                RoomMessageEventContent::text_plain("Done.")
+            }
+            AdminCommand::ClearServiceCaches { amount } => {
+                services().clear_caches(amount);
+
+                RoomMessageEventContent::text_plain("Done.")
+            }
             AdminCommand::ShowConfig => {
                 // Construct and send the response
                 RoomMessageEventContent::text_plain(format!("{}", services().globals.config))

src/service/globals/data.rs

@@ -15,7 +15,8 @@ pub trait Data: Send + Sync {
     fn current_count(&self) -> Result<u64>;
     async fn watch(&self, user_id: &UserId, device_id: &DeviceId) -> Result<()>;
     fn cleanup(&self) -> Result<()>;
-    fn memory_usage(&self) -> Result<String>;
+    fn memory_usage(&self) -> String;
+    fn clear_caches(&self, amount: u32);
     fn load_keypair(&self) -> Result<Ed25519KeyPair>;
     fn remove_keypair(&self) -> Result<()>;
     fn add_signing_key(

src/service/globals/mod.rs

@@ -214,10 +214,6 @@ impl Service {
         self.db.cleanup()
     }
 
-    pub fn memory_usage(&self) -> Result<String> {
-        self.db.memory_usage()
-    }
-
     pub fn server_name(&self) -> &ServerName {
         self.config.server_name.as_ref()
     }

src/service/mod.rs

@@ -90,7 +90,7 @@ impl Services {
                 state_compressor: rooms::state_compressor::Service {
                     db,
                     stateinfo_cache: Mutex::new(LruCache::new(
-                        (300.0 * config.conduit_cache_capacity_modifier) as usize,
+                        (100.0 * config.conduit_cache_capacity_modifier) as usize,
                     )),
                 },
                 timeline: rooms::timeline::Service {
@@ -115,4 +115,109 @@ impl Services {
             globals: globals::Service::load(db, config)?,
         })
     }
+    fn memory_usage(&self) -> String {
+        let lazy_load_waiting = self
+            .rooms
+            .lazy_loading
+            .lazy_load_waiting
+            .lock()
+            .unwrap()
+            .len();
+        let server_visibility_cache = self
+            .rooms
+            .state_accessor
+            .server_visibility_cache
+            .lock()
+            .unwrap()
+            .len();
+        let user_visibility_cache = self
+            .rooms
+            .state_accessor
+            .user_visibility_cache
+            .lock()
+            .unwrap()
+            .len();
+        let stateinfo_cache = self
+            .rooms
+            .state_compressor
+            .stateinfo_cache
+            .lock()
+            .unwrap()
+            .len();
+        let lasttimelinecount_cache = self
+            .rooms
+            .timeline
+            .lasttimelinecount_cache
+            .lock()
+            .unwrap()
+            .len();
+        let roomid_spacechunk_cache = self
+            .rooms
+            .spaces
+            .roomid_spacechunk_cache
+            .lock()
+            .unwrap()
+            .len();
+
+        format!(
+            "\
+lazy_load_waiting: {lazy_load_waiting}
+server_visibility_cache: {server_visibility_cache}
+user_visibility_cache: {user_visibility_cache}
+stateinfo_cache: {stateinfo_cache}
+lasttimelinecount_cache: {lasttimelinecount_cache}
+roomid_spacechunk_cache: {roomid_spacechunk_cache}\
+            "
+        )
+    }
+    fn clear_caches(&self, amount: u32) {
+        if amount > 0 {
+            self.rooms
+                .lazy_loading
+                .lazy_load_waiting
+                .lock()
+                .unwrap()
+                .clear();
+        }
+        if amount > 1 {
+            self.rooms
+                .state_accessor
+                .server_visibility_cache
+                .lock()
+                .unwrap()
+                .clear();
+        }
+        if amount > 2 {
+            self.rooms
+                .state_accessor
+                .user_visibility_cache
+                .lock()
+                .unwrap()
+                .clear();
+        }
+        if amount > 3 {
+            self.rooms
+                .state_compressor
+                .stateinfo_cache
+                .lock()
+                .unwrap()
+                .clear();
+        }
+        if amount > 4 {
+            self.rooms
+                .timeline
+                .lasttimelinecount_cache
+                .lock()
+                .unwrap()
+                .clear();
+        }
+        if amount > 5 {
+            self.rooms
+                .spaces
+                .roomid_spacechunk_cache
+                .lock()
+                .unwrap()
+                .clear();
+        }
+    }
 }