1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
use std::{
net::SocketAddr,
sync::Arc,
time::{Duration, SystemTime},
};
use crossbeam_deque::{Injector, Steal, Stealer, Worker};
use tokio::{
io::AsyncWriteExt,
net::{TcpListener, TcpStream},
sync::{
RwLock, Semaphore,
mpsc::{self, Sender},
},
task::yield_now,
};
use tracing::{error, info, warn};
use crate::application::server::lynn_server::{ReactorEventSender, TaskBodyOutChannel};
use crate::application::server::server_common::{add_client, check_handler_result, push_read_half};
use crate::domain::model::lynn_user::ClientsStructType;
use crate::domain::routing::router::LynnRouter;
use crate::domain::state::state_registry::StateRegistry;
use crate::infrastructure::connection::connection_limiter::ConnectionLimiter;
use crate::infrastructure::tcp::stream::{BoxedReadHalf, LynnStream, StreamAcceptor};
use crate::infrastructure::tcp::tcp_socket_config::TcpSocketConfig;
/// Reactor event type
enum EventType {
NewSocket((TcpStream, core::net::SocketAddr)),
ExcuteTask(TaskBodyOutChannel),
}
/// Event for the reactor system
pub(crate) struct ReactorEvent {
event_type: EventType,
}
impl ReactorEvent {
#[inline(always)]
fn new_with_event_type(event_type: EventType) -> Self {
Self { event_type }
}
#[inline(always)]
pub(crate) fn crate_new_socket_event(socket: TcpStream, addr: core::net::SocketAddr) -> Self {
ReactorEvent::new_with_event_type(EventType::NewSocket((socket, addr)))
}
#[inline(always)]
pub(crate) fn crate_excute_task_event(task_body: TaskBodyOutChannel) -> Self {
ReactorEvent::new_with_event_type(EventType::ExcuteTask(task_body))
}
}
/// Per-connection setup payload handed from the event workers to the
/// read-loop spawner task.
pub(crate) struct NewSocketTask {
/// The boxed read half of the accepted (and possibly TLS-wrapped) stream.
pub(crate) read_half: BoxedReadHalf,
pub(crate) process_permit: Arc<Semaphore>,
pub(crate) addr: SocketAddr,
pub(crate) clients: ClientsStructType,
pub(crate) message_header_mark: u16,
pub(crate) message_tail_mark: u16,
pub(crate) lynn_router: Arc<LynnRouter>,
pub(crate) reactor_event_sender: ReactorEventSender,
pub(crate) last_communicate_time: Arc<RwLock<SystemTime>>,
}
/// New socket event sender type
type NewSocketEventSender = Sender<NewSocketTask>;
/// Event manager - manages the work-stealing event queue
pub(crate) struct EventManager {
global_queue: ReactorEventSender,
}
impl EventManager {
pub(crate) fn new() -> Self {
let global_queue = Arc::new(Injector::<ReactorEvent>::new());
EventManager { global_queue }
}
#[allow(clippy::too_many_arguments)]
pub(crate) fn run(
&self,
clients: ClientsStructType,
server_single_processs_permit: &usize,
message_header_mark: u16,
message_tail_mark: u16,
lynn_router: Arc<LynnRouter>,
reactor_event_sender: ReactorEventSender,
tx: NewSocketEventSender,
server_max_reactor_taskpool_size: &usize,
stream_acceptor: Arc<StreamAcceptor>,
) {
let mut local_queues: Vec<Worker<ReactorEvent>> =
Vec::with_capacity(*server_max_reactor_taskpool_size);
let mut stealers: Vec<Stealer<ReactorEvent>> =
Vec::with_capacity(*server_max_reactor_taskpool_size);
for _ in 0..*server_max_reactor_taskpool_size {
let worker = Worker::new_fifo();
stealers.push(worker.stealer());
local_queues.push(worker);
}
let global_queue = self.global_queue.clone();
let stealers_arc = Arc::new(stealers);
for (index, local_queue) in local_queues.into_iter().enumerate() {
let global_queue_clone = global_queue.clone();
let stealers_arc_clone = stealers_arc.clone();
let clients_clone = clients.clone();
let server_single_processs_permit = *server_single_processs_permit;
let reactor_event_sender = reactor_event_sender.clone();
let tx = tx.clone();
let lynn_router = lynn_router.clone();
let stream_acceptor = stream_acceptor.clone();
let mut idle_count: u16 = 0;
tokio::spawn(async move {
let local_queue = local_queue;
let global_queue = global_queue_clone;
let stealers_arc = stealers_arc_clone;
let clients = clients_clone;
loop {
if let Some(event) =
get_event(&local_queue, &global_queue, &stealers_arc, index)
{
idle_count = 0;
match event.event_type {
EventType::NewSocket((socket, addr)) => {
// Perform the (optional) TLS handshake here, off the
// accept loop, so handshakes never serialize accepts.
let Some(stream) = stream_acceptor.accept(socket, addr).await
else {
continue;
};
let last_communicate_time =
Arc::new(RwLock::new(SystemTime::now()));
let read_half = add_client(
clients.clone(),
stream,
addr,
last_communicate_time.clone(),
)
.await;
let process_permit =
Arc::new(Semaphore::new(server_single_processs_permit));
let _ = tx
.send(NewSocketTask {
read_half,
process_permit,
addr,
clients: clients.clone(),
message_header_mark,
message_tail_mark,
lynn_router: lynn_router.clone(),
reactor_event_sender: reactor_event_sender.clone(),
last_communicate_time,
})
.await;
},
EventType::ExcuteTask(task_body) => {
let (task, context, clients) = task_body;
// Run the handler in a nested task so a panicking
// handler (e.g. a missing AppState) cannot take
// down this worker.
match tokio::spawn(async move { task.handler(context).await }).await
{
Ok(result) => {
check_handler_result(result, clients.clone()).await;
},
Err(join_error) => {
error!(
"Handler task panicked or was cancelled: {}",
join_error
);
},
}
},
}
} else {
idle_count += 1;
if idle_count < 32 {
// Temporarily relinquish control
yield_now().await;
} else if idle_count < 10_240 {
// A slightly longer wait
tokio::time::sleep(Duration::from_millis(1)).await;
} else if idle_count < 32767 {
// A slightly longer wait
tokio::time::sleep(Duration::from_millis(5)).await;
} else {
// Longer waiting time reduces CPU usage
tokio::time::sleep(Duration::from_millis(25)).await;
}
}
}
});
}
}
pub(crate) fn get_global_queue(&self) -> ReactorEventSender {
self.global_queue.clone()
}
}
#[inline(always)]
fn get_event(
local_queue: &Worker<ReactorEvent>,
global_queue: &ReactorEventSender,
stealers_arc: &Arc<Vec<Stealer<ReactorEvent>>>,
worker_index: usize,
) -> Option<ReactorEvent> {
// 1. local
if let Some(event) = local_queue.pop() {
return Some(event);
}
// 2. global
if let Steal::Success(event) = global_queue.steal_batch_and_pop(local_queue) {
return Some(event);
}
// 3. stealers
let stealers_len = stealers_arc.len();
if stealers_len > 1 {
let start_index = (worker_index + 1) % stealers_len;
for i in 0..stealers_len {
let steal_index = (start_index + i) % stealers_len;
match stealers_arc[steal_index].steal() {
Steal::Success(event) => return Some(event),
Steal::Empty | Steal::Retry => continue,
}
}
} else if stealers_len == 1 {
match stealers_arc[0].steal() {
Steal::Success(event) => return Some(event),
Steal::Empty | Steal::Retry => {},
}
}
None
}
/// Core reactor - handles TCP connections
pub(crate) struct CoreReactor {
pub(crate) tx: NewSocketEventSender,
}
impl CoreReactor {
pub(crate) fn new(states: Arc<StateRegistry>) -> Self {
let (tx, mut rx) = mpsc::channel::<NewSocketTask>(64);
tokio::spawn(async move {
while let Some(task) = rx.recv().await {
push_read_half(
task.read_half,
task.process_permit,
task.addr,
task.clients,
task.message_header_mark,
task.message_tail_mark,
task.lynn_router,
task.reactor_event_sender,
task.last_communicate_time,
states.clone(),
)
.await;
}
});
Self { tx }
}
pub(crate) async fn run(
&self,
tcp_listener: TcpListener,
clients: ClientsStructType,
alow_max_connections: Option<&usize>,
global_queue: ReactorEventSender,
connection_limiter: Option<(
&u64, // rate_limit
&usize, // max_connections_per_ip
Arc<ConnectionLimiter>,
)>,
tcp_config: TcpSocketConfig,
) {
loop {
// Waiting for a new link
let clinet_result = tcp_listener.accept().await;
if let Ok((socket, addr)) = clinet_result {
let mut socket_permit = true;
let mut socket = Some(socket);
// Apply TCP socket configuration
if let Some(ref s) = socket {
if let Err(e) = s.set_nodelay(tcp_config.nodelay) {
warn!(
"Failed to set TCP_NODELAY for {}: {}, using default",
addr, e
);
}
}
// Apply TCP keep-alive and buffer sizes using socket2
if tcp_config.keepalive_enabled
|| tcp_config.recv_buffer_size > 0
|| tcp_config.send_buffer_size > 0
{
if let Some(s) = socket.take() {
// Convert TcpStream to std::net::TcpStream to access socket2
match s.into_std() {
Ok(std_socket) => {
use socket2::Socket;
let socket2 = Socket::from(std_socket);
// Apply TCP keep-alive if enabled
if tcp_config.keepalive_enabled {
use socket2::TcpKeepalive;
let ka = TcpKeepalive::new().with_time(
std::time::Duration::from_secs(
tcp_config.keepalive_time_secs,
),
);
if let Err(e) = socket2.set_tcp_keepalive(&ka) {
warn!(
"Failed to set keep-alive for {}: {}, using default",
addr, e
);
}
}
// Set buffer sizes if specified (non-zero)
if tcp_config.recv_buffer_size > 0 {
if let Err(e) =
socket2.set_recv_buffer_size(tcp_config.recv_buffer_size)
{
warn!(
"Failed to set recv buffer size for {}: {}, using default",
addr, e
);
}
}
if tcp_config.send_buffer_size > 0 {
if let Err(e) =
socket2.set_send_buffer_size(tcp_config.send_buffer_size)
{
warn!(
"Failed to set send buffer size for {}: {}, using default",
addr, e
);
}
}
// Convert back to TcpStream
let std_socket: std::net::TcpStream = socket2.into();
match TcpStream::from_std(std_socket) {
Ok(new_s) => {
socket = Some(new_s);
},
Err(e) => {
warn!(
"Failed to convert back to TcpStream for {}: {}, closing connection",
addr, e
);
socket_permit = false;
},
}
},
Err(e) => {
warn!(
"Failed to convert TcpStream for {}: {}, using default settings",
addr, e
);
// Note: We lost the socket here, but this is a very rare error case
// In practice, this conversion should never fail
socket_permit = false;
},
}
}
}
// Check global max connections
if let Some(max_connections) = alow_max_connections {
if clients.len() >= *max_connections {
socket_permit = false;
warn!(
"Server socket's count is more than MAX_CONNECTIONS, can not accept new client:{}",
addr
);
}
}
// Check connection limiter (rate limit and per-IP limit)
if socket_permit {
if let Some((_, _, limiter)) = &connection_limiter {
let ip = addr.ip();
if !limiter.check_connection(ip).await {
socket_permit = false;
warn!(
"Connection from {} rejected by connection limiter (rate limit or per-IP limit exceeded)",
addr
);
}
}
}
if socket_permit {
if let Some(s) = socket {
info!("Accepted connection from: {}", addr);
global_queue.push(ReactorEvent::crate_new_socket_event(s, addr));
}
} else {
if let Some(mut s) = socket {
let _ = s.shutdown().await;
}
}
} else {
if let Err(e) = clinet_result {
warn!(
"Failed to accept connection, server run next, e :{}",
e.to_string()
);
}
}
}
}
}
/// TcpReactor - the main reactor struct
pub(crate) struct TcpReactor {
core_reactor: CoreReactor,
event_manager: EventManager,
}
impl TcpReactor {
pub(crate) fn new(states: Arc<StateRegistry>) -> Self {
Self {
core_reactor: CoreReactor::new(states),
event_manager: EventManager::new(),
}
}
#[allow(clippy::too_many_arguments)]
pub(crate) async fn start(
&self,
clients: ClientsStructType,
server_single_processs_permit: &usize,
message_header_mark: u16,
message_tail_mark: u16,
lynn_router: Arc<LynnRouter>,
tcp_listener: TcpListener,
alow_max_connections: Option<&usize>,
server_max_reactor_taskpool_size: &usize,
connection_limiter: Option<(
&u64, // rate_limit
&usize, // max_connections_per_ip
Arc<ConnectionLimiter>,
)>,
tcp_config: TcpSocketConfig,
stream_acceptor: Arc<StreamAcceptor>,
) {
self.event_manager.run(
clients.clone(),
server_single_processs_permit,
message_header_mark,
message_tail_mark,
lynn_router,
self.event_manager.get_global_queue(),
self.core_reactor.tx.clone(),
server_max_reactor_taskpool_size,
stream_acceptor,
);
// Spawn cleanup task for connection limiter if rate limiting is enabled
if let Some((rate_limit, _, limiter)) = &connection_limiter {
if **rate_limit > 0 {
limiter.clone().spawn_cleanup_task();
}
}
self.core_reactor
.run(
tcp_listener,
clients,
alow_max_connections,
self.event_manager.get_global_queue(),
connection_limiter,
tcp_config,
)
.await;
}
}