Revert "Enable multithreading on P2P deserialization workload"

src/Nethermind/Nethermind.Init/Steps/InitializeNetwork.cs

@@ -495,7 +495,6 @@ private async Task InitPeer()
             encryptionHandshakeServiceA,
             _api.SessionMonitor,
             _api.DisconnectsAnalyzer,
-            _networkConfig.P2PHandlerThreadCount,
             _api.LogManager);
 
         await _api.RlpxPeer.Init();

src/Nethermind/Nethermind.Network.Test/Rlpx/RlpxPeerTests.cs

@@ -1,16 +1,16 @@
 //  Copyright (c) 2021 Demerzel Solutions Limited
 //  This file is part of the Nethermind library.
-//
+// 
 //  The Nethermind library is free software: you can redistribute it and/or modify
 //  it under the terms of the GNU Lesser General Public License as published by
 //  the Free Software Foundation, either version 3 of the License, or
 //  (at your option) any later version.
-//
+// 
 //  The Nethermind library is distributed in the hope that it will be useful,
 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 //  GNU Lesser General Public License for more details.
-//
+// 
 //  You should have received a copy of the GNU Lesser General Public License
 //  along with the Nethermind. If not, see <http://www.gnu.org/licenses/>.
 
@@ -40,7 +40,6 @@ public async Task Start_stop()
                 Substitute.For<IHandshakeService>(),
                 Substitute.For<ISessionMonitor>(),
                 NullDisconnectsAnalyzer.Instance,
-                1,
                 LimboLogs.Instance);
             await host.Init();
             await host.Shutdown();

src/Nethermind/Nethermind.Network/Config/INetworkConfig.cs

@@ -1,16 +1,16 @@
 //  Copyright (c) 2021 Demerzel Solutions Limited
 //  This file is part of the Nethermind library.
-//
+// 
 //  The Nethermind library is free software: you can redistribute it and/or modify
 //  it under the terms of the GNU Lesser General Public License as published by
 //  the Free Software Foundation, either version 3 of the License, or
 //  (at your option) any later version.
-//
+// 
 //  The Nethermind library is distributed in the hope that it will be useful,
 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 //  GNU Lesser General Public License for more details.
-//
+// 
 //  You should have received a copy of the GNU Lesser General Public License
 //  along with the Nethermind. If not, see <http://www.gnu.org/licenses/>.
 
@@ -81,8 +81,5 @@ public interface INetworkConfig : IConfig
 
         [ConfigItem(DefaultValue = "", Description = "Bootnodes")]
         string Bootnodes { get; set; }
-
-        [ConfigItem(DefaultValue = "0", Description = "[TECHNICAL] Set P2P handler thread count. Set this to a low number such as 1 or 2 if you have too slow block processing during old bodies or old receipts sync which may cause missed attestation. Defaults to processor count - 2.")]
-        int P2PHandlerThreadCount { get; set; }
     }
 }

src/Nethermind/Nethermind.Network/Config/NetworkConfig.cs

@@ -1,16 +1,16 @@
 //  Copyright (c) 2021 Demerzel Solutions Limited
 //  This file is part of the Nethermind library.
-//
+// 
 //  The Nethermind library is free software: you can redistribute it and/or modify
 //  it under the terms of the GNU Lesser General Public License as published by
 //  the Free Software Foundation, either version 3 of the License, or
 //  (at your option) any later version.
-//
+// 
 //  The Nethermind library is distributed in the hope that it will be useful,
 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 //  GNU Lesser General Public License for more details.
-//
+// 
 //  You should have received a copy of the GNU Lesser General Public License
 //  along with the Nethermind. If not, see <http://www.gnu.org/licenses/>.
 
@@ -42,6 +42,5 @@ public class NetworkConfig : INetworkConfig
         public string Bootnodes { get; set; } = string.Empty;
         public int DiscoveryPort { get; set; } = 30303;
         public int P2PPort { get; set; } = 30303;
-        public int P2PHandlerThreadCount { get; set; } = 0;
     }
 }

src/Nethermind/Nethermind.Network/Rlpx/NettyHandshakeHandler.cs

@@ -1,16 +1,16 @@
 //  Copyright (c) 2021 Demerzel Solutions Limited
 //  This file is part of the Nethermind library.
-//
+// 
 //  The Nethermind library is free software: you can redistribute it and/or modify
 //  it under the terms of the GNU Lesser General Public License as published by
 //  the Free Software Foundation, either version 3 of the License, or
 //  (at your option) any later version.
-//
+// 
 //  The Nethermind library is distributed in the hope that it will be useful,
 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 //  GNU Lesser General Public License for more details.
-//
+// 
 //  You should have received a copy of the GNU Lesser General Public License
 //  along with the Nethermind. If not, see <http://www.gnu.org/licenses/>.
 

src/Nethermind/Nethermind.Network/Rlpx/RlpxHost.cs

@@ -1,16 +1,16 @@
 //  Copyright (c) 2021 Demerzel Solutions Limited
 //  This file is part of the Nethermind library.
-//
+// 
 //  The Nethermind library is free software: you can redistribute it and/or modify
 //  it under the terms of the GNU Lesser General Public License as published by
 //  the Free Software Foundation, either version 3 of the License, or
 //  (at your option) any later version.
-//
+// 
 //  The Nethermind library is distributed in the hope that it will be useful,
 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 //  GNU Lesser General Public License for more details.
-//
+// 
 //  You should have received a copy of the GNU Lesser General Public License
 //  along with the Nethermind. If not, see <http://www.gnu.org/licenses/>.
 
@@ -54,17 +54,14 @@ public class RlpxHost : IRlpxHost
         private readonly ILogger _logger;
         private readonly ISessionMonitor _sessionMonitor;
         private readonly IDisconnectsAnalyzer _disconnectsAnalyzer;
-
-        // Main executor group. Used to execute snappy decompression and message deserialization.
-        private readonly IEventExecutorGroup _group;
+        private IEventExecutorGroup _group;
 
         public RlpxHost(IMessageSerializationService serializationService,
             PublicKey localNodeId,
             int localPort,
             IHandshakeService handshakeService,
             ISessionMonitor sessionMonitor,
             IDisconnectsAnalyzer disconnectsAnalyzer,
-            int handlerThreadCount,
             ILogManager logManager)
         {
             // .NET Core definitely got the easy logging setup right :D
@@ -82,15 +79,7 @@ public RlpxHost(IMessageSerializationService serializationService,
             //     new LoggerFilterOptions { MinLevel = Microsoft.Extensions.Logging.LogLevel.Warning });
             // InternalLoggerFactory.DefaultFactory = loggerFactory;
 
-            if (handlerThreadCount == 0)
-            {
-                // Using slightly less than processor count to give some compute for other tasks
-                // The thread count is rarely a limit, outside of old bodies/old receipts, but it may improve
-                // some latency as a peer message may get blocked by another peer's message deserialization
-                // if thread count is 1.
-                handlerThreadCount = Math.Max(1, Environment.ProcessorCount - 2);
-            }
-            _group = new MultithreadEventLoopGroup(handlerThreadCount);
+            _group = new SingleThreadEventLoop();
             _serializationService = serializationService ?? throw new ArgumentNullException(nameof(serializationService));
             _logManager = logManager ?? throw new ArgumentNullException(nameof(logManager));
             _logger = logManager.GetClassLogger();