Refresh message statistics after tracking messages in a background thread

app/Desktop/Main/Pages/DebugPageModel.cs

@@ -53,9 +53,12 @@ namespace DHT.Desktop.Main.Pages {
 			await progressDialog.ShowDialog(window);
 		}
 		
-		private const int BatchSize = 100;
+		private const int BatchSize = 500;
 		
 		private async Task GenerateRandomData(int channelCount, int userCount, int messageCount, IProgressCallback callback) {
+			int batchCount = (messageCount + BatchSize - 1) / BatchSize;
+			await callback.Update("Adding messages in batches of " + BatchSize, 0, batchCount);
+
 			var rand = new Random();
 			var server = new DHT.Server.Data.Server {
 				Id = RandomId(rand),
@@ -87,9 +90,6 @@ namespace DHT.Desktop.Main.Pages {
 				db.AddChannel(channel);
 			}
 			
-			int batchCount = (messageCount + BatchSize - 1) / BatchSize;
-			await callback.Update("Adding messages in batches of 100", 0, batchCount);
-
 			var now = DateTimeOffset.Now;
 			int batchIndex = 0;
 			
@@ -119,8 +119,8 @@ namespace DHT.Desktop.Main.Pages {
 				
 				db.AddMessages(messages);
 				
-				messageCount -= 100;
-				await callback.Update("Adding messages in batches of 100", ++batchIndex, batchCount);
+				messageCount -= BatchSize;
+				await callback.Update("Adding messages in batches of " + BatchSize, ++batchIndex, batchCount);
 			}
 		}
 

app/Server/Database/Sqlite/SqliteDatabaseFile.cs

@@ -36,10 +36,13 @@ namespace DHT.Server.Database.Sqlite {
 
 		private readonly Log log;
 		private readonly SqliteConnectionPool pool;
+		private readonly SqliteMessageStatisticsThread messageStatisticsThread;
 
 		private SqliteDatabaseFile(string path, SqliteConnectionPool pool) {
 			this.log = Log.ForType(typeof(SqliteDatabaseFile), System.IO.Path.GetFileName(path));
 			this.pool = pool;
+			this.messageStatisticsThread = new SqliteMessageStatisticsThread(pool, UpdateMessageStatistics);
+
 			this.Path = path;
 			this.Statistics = new DatabaseStatistics();
 
@@ -51,6 +54,7 @@ namespace DHT.Server.Database.Sqlite {
 		}
 
 		public void Dispose() {
+			messageStatisticsThread.Dispose();
 			pool.Dispose();
 		}
 
@@ -299,7 +303,7 @@ namespace DHT.Server.Database.Sqlite {
 			}
 
 			tx.Commit();
-			UpdateMessageStatistics(conn);
+			messageStatisticsThread.RequestUpdate();
 		}
 
 		public int CountMessages(MessageFilter? filter = null) {

app/Server/Database/Sqlite/SqliteMessageStatisticsThread.cs

@@ -0,0 +1,54 @@
+using System;
+using System.Threading;
+using DHT.Server.Database.Sqlite.Utils;
+
+namespace DHT.Server.Database.Sqlite {
+	sealed class SqliteMessageStatisticsThread : IDisposable {
+		private readonly SqliteConnectionPool pool;
+		private readonly Action<ISqliteConnection> action;
+		
+		private readonly CancellationTokenSource cancellationTokenSource = new();
+		private readonly CancellationToken cancellationToken;
+		
+		private readonly AutoResetEvent requestEvent = new (false);
+
+		public SqliteMessageStatisticsThread(SqliteConnectionPool pool, Action<ISqliteConnection> action) {
+			this.pool = pool;
+			this.action = action;
+			
+			this.cancellationToken = cancellationTokenSource.Token;
+			
+			var thread = new Thread(RunThread) {
+				Name = "DHT message statistics thread",
+				IsBackground = true
+			};
+			thread.Start();
+		}
+
+		public void Dispose() {
+			try {
+				cancellationTokenSource.Cancel();
+			} catch (ObjectDisposedException) {}
+		}
+
+		public void RequestUpdate() {
+			try {
+				requestEvent.Set();
+			} catch (ObjectDisposedException) {}
+		}
+
+		private void RunThread() {
+			try {
+				while (!cancellationToken.IsCancellationRequested) {
+					if (requestEvent.WaitOne(TimeSpan.FromMilliseconds(100))) {
+						using var conn = pool.Take();
+						action(conn);
+					}
+				}
+			} finally {
+				cancellationTokenSource.Dispose();
+				requestEvent.Dispose();
+			}
+		}
+	}
+}

app/Server/Database/Sqlite/Utils/SqliteConnectionPool.cs

@@ -24,7 +24,14 @@ namespace DHT.Server.Database.Sqlite.Utils {
 			for (int i = 0; i < poolSize; i++) {
 				var conn = new SqliteConnection(connectionString);
 				conn.Open();
-				free.Add(new PooledConnection(this, conn));
+				
+				var pooledConn = new PooledConnection(this, conn);
+				
+				using (var cmd = pooledConn.Command("PRAGMA journal_mode=WAL")) {
+					cmd.ExecuteNonQuery();
+				}
+				
+				free.Add(pooledConn);
 			}
 
 			used = new List<PooledConnection>(poolSize);