Move order latency control to the server.

This commit is contained in:
Paul Chote
2021-09-02 22:08:28 +01:00
committed by abcdefg30
parent 6421c17515
commit 8f412f869d
9 changed files with 120 additions and 45 deletions

View File

@@ -167,10 +167,7 @@ namespace OpenRA
map = ModData.PrepareMap(mapUID);
using (new PerfTimer("NewWorld"))
{
OrderManager.World = new World(ModData, map, OrderManager, type);
OrderManager.FramesAhead = OrderManager.World.OrderLatency;
}
OrderManager.World.GameOver += FinishBenchmark;

View File

@@ -32,6 +32,7 @@ namespace OpenRA.Network
public interface IConnection : IDisposable
{
int LocalClientId { get; }
void StartGame();
void Send(int frame, IEnumerable<Order> orders);
void SendImmediate(IEnumerable<Order> orders);
void SendSync(int frame, int syncHash, ulong defeatState);
@@ -47,6 +48,12 @@ namespace OpenRA.Network
int IConnection.LocalClientId => LocalClientId;
void IConnection.StartGame()
{
// Inject an empty frame to fill the gap we are making by projecting forward orders
orders.Enqueue((0, new OrderPacket(Array.Empty<Order>())));
}
void IConnection.Send(int frame, IEnumerable<Order> o)
{
orders.Enqueue((frame, new OrderPacket(o.ToArray())));
@@ -67,8 +74,9 @@ namespace OpenRA.Network
while (immediateOrders.TryDequeue(out var i))
orderManager.ReceiveImmediateOrders(LocalClientId, i);
// Project orders forward to the next frame
while (orders.TryDequeue(out var o))
orderManager.ReceiveOrders(LocalClientId, o);
orderManager.ReceiveOrders(LocalClientId, (o.Frame + 1, o.Orders));
while (sync.TryDequeue(out var s))
orderManager.ReceiveSync(s);
@@ -207,6 +215,8 @@ namespace OpenRA.Network
int IConnection.LocalClientId => clientId;
void IConnection.StartGame() { }
void IConnection.Send(int frame, IEnumerable<Order> orders)
{
var o = new OrderPacket(orders.ToArray());
@@ -270,19 +280,26 @@ namespace OpenRA.Network
Recorder?.Receive(clientId, OrderIO.SerializeSync(s));
}
while (sentOrders.TryDequeue(out var o))
{
orderManager.ReceiveOrders(clientId, o);
Recorder?.Receive(clientId, o.Orders.Serialize(o.Frame));
}
// Orders from other players
while (receivedPackets.TryDequeue(out var p))
{
var record = true;
if (OrderIO.TryParseDisconnect(p.Data, out var disconnectClient))
orderManager.ReceiveDisconnect(disconnectClient);
else if (OrderIO.TryParseSync(p.Data, out var sync))
orderManager.ReceiveSync(sync);
else if (OrderIO.TryParseAck(p, out var ackFrame))
{
if (!sentOrders.TryDequeue(out var q))
throw new InvalidOperationException("Received Ack with empty send queue");
// The Acknowledgement packet is a placeholder that tells us to process the first packet in our
// local sent buffer and the frame at which it should be applied. This is an optimization to avoid having
// to send the (much larger than 5 byte) packet back to us over the network.
orderManager.ReceiveOrders(clientId, (ackFrame, q.Orders));
Recorder?.Receive(clientId, q.Orders.Serialize(ackFrame));
record = false;
}
else if (OrderIO.TryParseOrderPacket(p.Data, out var orders))
{
if (orders.Frame == 0)
@@ -293,7 +310,8 @@ namespace OpenRA.Network
else
throw new InvalidDataException($"Received unknown packet from client {p.FromClient} with length {p.Data.Length}");
Recorder?.Receive(p.FromClient, p.Data);
if (record)
Recorder?.Receive(p.FromClient, p.Data);
}
}

View File

@@ -18,6 +18,7 @@ namespace OpenRA
{
public enum OrderType : byte
{
Ack = 0x10,
SyncHash = 0x65,
Disconnect = 0xBF,
Handshake = 0xFE,

View File

@@ -106,6 +106,19 @@ namespace OpenRA.Network
return true;
}
public static bool TryParseAck((int FromClient, byte[] Data) packet, out int frame)
{
// Ack packets are only accepted from the server
if (packet.FromClient != 0 || packet.Data.Length != 5 || packet.Data[4] != (byte)OrderType.Ack)
{
frame = 0;
return false;
}
frame = BitConverter.ToInt32(packet.Data, 0);
return true;
}
public static bool TryParseOrderPacket(byte[] packet, out (int Frame, OrderPacket Orders) data)
{
// Not a valid packet

View File

@@ -33,7 +33,6 @@ namespace OpenRA.Network
public int NetFrameNumber { get; private set; }
public int LocalFrameNumber;
public int FramesAhead = 0;
public TickTime LastTickTime;
@@ -52,6 +51,7 @@ namespace OpenRA.Network
bool disposed;
bool generateSyncReport = false;
int sentOrdersFrame = 0;
public struct ClientOrder
{
@@ -87,9 +87,7 @@ namespace OpenRA.Network
LocalFrameNumber = 0;
LastTickTime.Value = Game.RunTime;
if (GameSaveLastFrame < 0)
for (var i = NetFrameNumber; i <= FramesAhead; i++)
Connection.Send(i, Array.Empty<Order>());
Connection.StartGame();
}
public OrderManager(IConnection conn)
@@ -123,7 +121,7 @@ namespace OpenRA.Network
void SendImmediateOrders()
{
if (localImmediateOrders.Count != 0 && GameSaveLastFrame < NetFrameNumber + FramesAhead)
if (localImmediateOrders.Count != 0 && GameSaveLastFrame < NetFrameNumber)
Connection.SendImmediate(localImmediateOrders);
localImmediateOrders.Clear();
}
@@ -206,13 +204,11 @@ namespace OpenRA.Network
void SendOrders()
{
if (!GameStarted)
return;
if (GameSaveLastFrame < NetFrameNumber + FramesAhead)
if (GameStarted && GameSaveLastFrame < NetFrameNumber && sentOrdersFrame < NetFrameNumber)
{
Connection.Send(NetFrameNumber + FramesAhead, localOrders);
Connection.Send(NetFrameNumber, localOrders);
localOrders.Clear();
sentOrdersFrame = NetFrameNumber;
}
}
@@ -225,10 +221,9 @@ namespace OpenRA.Network
// The IsReadyForNextFrame check above guarantees that all clients have sent a packet
var (frameNumber, orders) = frameOrders.Dequeue();
// Orders are synchronised by sending an initial FramesAhead set of empty packets
// and then making sure that we enqueue and process exactly one packet for each player each tick.
// This may change in the future, so sanity check that the orders are for the frame we expect
// and crash early instead of risking desyncs.
// We expect every frame to have a queued order packet, even if it contains no orders, as this
// controls the pacing of the game simulation.
// Sanity check that we are processing the frame that we expect, so we can crash early instead of desyncing.
if (frameNumber != NetFrameNumber)
throw new InvalidDataException($"Attempted to process orders from client {clientId} for frame {frameNumber} on frame {NetFrameNumber}");
@@ -239,7 +234,7 @@ namespace OpenRA.Network
}
}
if (NetFrameNumber + FramesAhead >= GameSaveLastSyncFrame)
if (NetFrameNumber >= GameSaveLastSyncFrame)
{
var defeatState = 0UL;
for (var i = 0; i < World.Players.Length; i++)

View File

@@ -124,6 +124,8 @@ namespace OpenRA.Network
ordersFrame = orderLatency;
}
void IConnection.StartGame() { }
// Do nothing: ignore locally generated orders
void IConnection.Send(int frame, IEnumerable<Order> orders) { }
void IConnection.SendImmediate(IEnumerable<Order> orders) { }

View File

@@ -35,6 +35,8 @@ namespace OpenRA.Server
// - Length-prefixed string specifying the order name
// - OrderFields enum encoded as a byte: specifies the data included in the rest of the order
// - Order-specific data - see OpenRA.Game/Server/Order.cs for details
// - 0x10: Order acknowledgement (sent from the server to a client in response to a packet with world orders)
// - Int32 containing the frame number that the client should apply the orders it sent
//
// A connection handshake begins when a client opens a connection to the server:
// - Server sends:
@@ -68,6 +70,6 @@ namespace OpenRA.Server
// The protocol for server and world orders
// This applies after the handshake has completed, and is provided to support
// alternative server implementations that wish to support multiple versions in parallel
public const int Orders = 13;
public const int Orders = 14;
}
}

View File

@@ -61,6 +61,9 @@ namespace OpenRA.Server
public readonly MapStatusCache MapStatusCache;
public GameSave GameSave = null;
// Default to the next frame for ServerType.Local - MP servers take the value from the selected GameSpeed.
public int OrderLatency = 1;
readonly int randomSeed;
readonly List<TcpListener> listeners = new List<TcpListener>();
readonly TypeDictionary serverTraits = new TypeDictionary();
@@ -611,14 +614,22 @@ namespace OpenRA.Server
byte[] CreateFrame(int client, int frame, byte[] data)
{
using (var ms = new MemoryStream(data.Length + 12))
{
ms.WriteArray(BitConverter.GetBytes(data.Length + 4));
ms.WriteArray(BitConverter.GetBytes(client));
ms.WriteArray(BitConverter.GetBytes(frame));
ms.WriteArray(data);
return ms.GetBuffer();
}
var ms = new MemoryStream(data.Length + 12);
ms.WriteArray(BitConverter.GetBytes(data.Length + 4));
ms.WriteArray(BitConverter.GetBytes(client));
ms.WriteArray(BitConverter.GetBytes(frame));
ms.WriteArray(data);
return ms.GetBuffer();
}
byte[] CreateAckFrame(int frame)
{
var ms = new MemoryStream(13);
ms.WriteArray(BitConverter.GetBytes(5));
ms.WriteArray(BitConverter.GetBytes(0));
ms.WriteArray(BitConverter.GetBytes(frame));
ms.WriteByte((byte)OrderType.Ack);
return ms.GetBuffer();
}
void DispatchOrdersToClient(Connection c, int client, int frame, byte[] data)
@@ -784,10 +795,23 @@ namespace OpenRA.Server
if (frame == 0)
InterpretServerOrders(conn, data);
else
DispatchOrdersToClients(conn, frame, data);
{
// Non-immediate orders must be projected into the future so that all players can
// apply them on the same world tick. We can do this directly when forwarding the
// packet on to other clients, but sending the same data back to the client that
// sent it just to update the frame number would be wasteful. We instead send them
// a separate Ack packet that tells them to apply the order from a locally stored queue.
// TODO: Replace static latency with a dynamic order buffering system
if (data.Length == 0 || data[0] != (byte)OrderType.SyncHash)
{
frame += OrderLatency;
DispatchFrameToClient(conn, conn.PlayerIndex, CreateAckFrame(frame));
}
if (GameSave != null)
GameSave.DispatchOrders(conn, frame, data);
DispatchOrdersToClients(conn, frame, data);
}
GameSave?.DispatchOrders(conn, frame, data);
}
void InterpretServerOrders(Connection conn, byte[] data)
@@ -1205,6 +1229,13 @@ namespace OpenRA.Server
SyncLobbyInfo();
State = ServerState.GameStarted;
if (Type != ServerType.Local)
{
var gameSpeeds = Game.ModData.Manifest.Get<GameSpeeds>();
var gameSpeedName = LobbyInfo.GlobalSettings.OptionOrDefault("gamespeed", gameSpeeds.DefaultSpeed);
OrderLatency = gameSpeeds.Speeds[gameSpeedName].OrderLatency;
}
if (GameSave == null && LobbyInfo.GlobalSettings.GameSavesEnabled)
GameSave = new GameSave();
@@ -1227,6 +1258,7 @@ namespace OpenRA.Server
foreach (var t in serverTraits.WithInterface<IStartGame>())
t.GameStarted(this);
var firstFrame = 1;
if (GameSave != null && GameSave.LastOrdersFrame >= 0)
{
GameSave.ParseOrders(LobbyInfo, (frame, client, data) =>
@@ -1235,6 +1267,28 @@ namespace OpenRA.Server
if (c.Validated)
DispatchOrdersToClient(c, client, frame, data);
});
firstFrame += GameSave.LastOrdersFrame;
}
// ReceiveOrders projects player orders into the future so that all players can
// apply them on the same world tick.
// Clients require every frame to have an orders packet associated with it, so we must
// inject an empty packet for each frame that we are skipping forwards.
// TODO: Replace static latency with a dynamic order buffering system
var conns = Conns.Where(c => c.Validated).ToList();
foreach (var from in conns)
{
for (var i = 0; i < OrderLatency; i++)
{
var frame = firstFrame + i;
var frameData = CreateFrame(from.PlayerIndex, frame, Array.Empty<byte>());
foreach (var to in conns)
DispatchFrameToClient(to, from.PlayerIndex, frameData);
RecordOrder(frame, Array.Empty<byte>(), from.PlayerIndex);
GameSave?.DispatchOrders(from, frame, Array.Empty<byte>());
}
}
}
}

View File

@@ -39,7 +39,6 @@ namespace OpenRA
public readonly GameSpeed GameSpeed;
public readonly int Timestep;
public readonly int OrderLatency;
public int ReplayTimestep;
@@ -189,13 +188,7 @@ namespace OpenRA
var gameSpeeds = modData.Manifest.Get<GameSpeeds>();
var gameSpeedName = orderManager.LobbyInfo.GlobalSettings.OptionOrDefault("gamespeed", gameSpeeds.DefaultSpeed);
GameSpeed = gameSpeeds.Speeds[gameSpeedName];
Timestep = ReplayTimestep = GameSpeed.Timestep;
OrderLatency = GameSpeed.OrderLatency;
// HACK: Turn down the latency if there is only one real player/spectator
if (orderManager.LobbyInfo.NonBotClients.Count() == 1)
OrderLatency = 1;
SharedRandom = new MersenneTwister(orderManager.LobbyInfo.GlobalSettings.RandomSeed);
LocalRandom = new MersenneTwister();