laysense/laylink
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

KCP Improving

Browse Source
This commit is contained in:
EchoNoch 2026-05-30 18:09:09 +08:00
parent 56c74337e4
commit 38797fe078
9 changed files with 121 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
.env.example
View File

@ -27,22 +27,22 @@ LAYLINK_KCP_INTERVAL_MS=10
# KCP 内部 update 间隔；单位毫秒。常用 10、20、30，越小越低延迟但 CPU/发包更高。
LAYLINK_KCP_FAST_RESEND=2
# KCP 快速重传阈值；0 关闭，2 是常见低延迟设置，丢包网络可尝试 2-4。
LAYLINK_KCP_NO_CONGESTION_CONTROL=0
# 是否关闭 KCP 拥塞控制；0 开启拥塞控制更稳，1 更激进但容易挤爆 UDP 发送缓冲。
LAYLINK_KCP_SEND_WINDOW=256
# KCP 发送窗口；越大吞吐潜力越高但更容易拥堵，常用 128、256、512、1024。
LAYLINK_KCP_RECV_WINDOW=512
# KCP 接收窗口；应不小于发送窗口，常用 256、512、1024。
LAYLINK_KCP_MTU_BYTES=1200
# KCP MTU；建议 1200 避免公网路径分片，内网可尝试 1350。
LAYLINK_KCP_NO_CONGESTION_CONTROL=1
# 是否关闭 KCP 拥塞控制；1 为高吞吐模式，接近早期 100Mbps 默认值；丢包/拥堵明显时改 0。
LAYLINK_KCP_SEND_WINDOW=1024
# KCP 发送窗口；高吞吐建议 1024，保守可用 256 或 512。
LAYLINK_KCP_RECV_WINDOW=1024
# KCP 接收窗口；应不小于发送窗口，高吞吐建议 1024。
LAYLINK_KCP_MTU_BYTES=1350
# KCP MTU；高吞吐建议 1350，若公网链路分片/丢包明显则改 1200。
LAYLINK_KCP_TICK_MS=10
# PHP transport tick 间隔；单位毫秒。通常与 LAYLINK_KCP_INTERVAL_MS 一致。
LAYLINK_KCP_UDP_SEND_QUEUE_BYTES=16777216
# UDP EAGAIN 发送队列上限；单位字节。发送缓冲暂满时会排队重试，超过后关闭该 KCP 会话。
LAYLINK_KCP_UDP_FLUSH_PACKETS=256
# 每次 tick 最多刷出的 UDP packet 数；拥堵时可调低到 64 或 128，追求吞吐可调高。
LAYLINK_KCP_OUTPUT_DRAIN_PACKETS=256
# 每次从 native KCP 输出队列搬到 UDP 发送队列的最大 packet 数；调低可减少单个大下载占用事件循环时间。
LAYLINK_KCP_UDP_SEND_QUEUE_BYTES=67108864
# UDP EAGAIN 发送队列上限；单位字节。高吞吐建议 67108864，内存紧张或拥堵明显时调低。
LAYLINK_KCP_UDP_FLUSH_PACKETS=1024
# 每次 tick 最多刷出的 UDP packet 数；高吞吐建议 1024，拥堵时可调低到 256 或 128。
LAYLINK_KCP_OUTPUT_DRAIN_PACKETS=1024
# 每次从 native KCP 输出队列搬到 UDP 发送队列的最大 packet 数；高吞吐建议 1024，单连接影响事件循环时调低。
[client-agent]
NODE_ID=client-01

17
contract.md
View File

@ -2,7 +2,7 @@
## Implementation Status
Last updated: 2026-05-29 Asia/Shanghai.
Last updated: 2026-05-30 Asia/Shanghai.
Current phase: MVP bootstrap in progress.
@ -240,6 +240,21 @@ Completed in this checkpoint:
* `POP_AGENT_KCP_WORKERS` is exposed but currently clamped to `1` in `bin/pop-server.php`.
* KCP/UDP must remain single-worker in the current architecture because KCP session state is process-local and UDP packets for one conv can otherwise be handled by different workers.
* Native KCP output draining is capped per tick by `LAYLINK_KCP_OUTPUT_DRAIN_PACKETS` to reduce single-flow event-loop monopolization during large downloads.
* Fixed KCP POP-side session lookup for real-world UDP/NAT behavior:
* POP no longer depends only on `remote ip:port + conv` for KCP session lookup.
* POP keeps a `conv -> session` index and migrates the current UDP remote address when a known `conv` arrives from a changed source port.
* KCP callbacks now resolve the active connection by `conv`, so migrated sessions continue delivering frames instead of silently dropping `DATA`.
* Fixed native KCP send-buffer accounting after heavy speedtest-style traffic:
* The previous PHP-side native KCP `queuedBytes` counter could grow during large transfers and never fall back to zero unless user payload was received in the opposite direction.
* This could make a long-lived KCP Agent connection permanently appear full after upload/download tests, causing later `OPEN_OK` / `DATA` sends to fail and audit rows to show zero transferred bytes.
* Added native wrapper `laylink_kcp_waitsnd()` around upstream `ikcp_waitsnd()`.
* `NativeKcpSession::getSendBufferQueueSize()` now derives watermarks from real KCP pending segment count plus pending UDP output bytes.
* POP now treats failure to send `OPEN_OK` as `agent_buffer_overflow` instead of leaving a target connection open with no client-visible success.
* Restored KCP high-throughput defaults:
* Early native KCP testing used hardcoded `nodelay=1, interval=10, resend=2, nc=1, sndwnd=1024, rcvwnd=1024, mtu=1350`.
* The first exposed `.env` defaults were more conservative (`nc=0`, smaller windows, `mtu=1200`) and could reduce throughput dramatically on speedtest-style high-BDP paths.
* `NativeKcpSession`, KCP UDP queue/flush fallback defaults, current `.env`, and `.env.example` now use the high-throughput profile by default.
* For lossy or congested paths, tune down to `LAYLINK_KCP_NO_CONGESTION_CONTROL=0`, `LAYLINK_KCP_MTU_BYTES=1200`, smaller windows, or lower flush/drain packet counts.
Known MVP limitations:

7
native/kcp/laylink_kcp.c
View File

@ -164,6 +164,13 @@ void laylink_kcp_flush(laylink_kcp* session) {
ikcp_flush(session->kcp);
}
int laylink_kcp_waitsnd(laylink_kcp* session) {
if (session == NULL || session->kcp == NULL) {
return 0;
}
return ikcp_waitsnd(session->kcp);
}
int laylink_kcp_pending_output_size(laylink_kcp* session) {
if (session == NULL || session->output_head == NULL) {
return 0;

1
native/kcp/laylink_kcp.h
View File

@ -19,6 +19,7 @@ unsigned int laylink_kcp_check(laylink_kcp* session, unsigned int current);
int laylink_kcp_peeksize(laylink_kcp* session);
int laylink_kcp_recv(laylink_kcp* session, char* buffer, int len);
void laylink_kcp_flush(laylink_kcp* session);
int laylink_kcp_waitsnd(laylink_kcp* session);
int laylink_kcp_pending_output_size(laylink_kcp* session);
int laylink_kcp_pop_output(laylink_kcp* session, char* buffer, int len);

5
src/Server/AgentListener.php
View File

@ -237,10 +237,13 @@ final class AgentListener
$target->onConnect = function () use ($session, $agentConnection): void {
$session->state = TunnelSession::OPEN;
$this->send($agentConnection, new Frame(FrameType::OPEN_OK, $session->sessionId, [
$sent = $this->send($agentConnection, new Frame(FrameType::OPEN_OK, $session->sessionId, [
'target_host' => $session->targetHost,
'target_port' => $session->targetPort,
]));
if ($sent === false) {
$this->closeSession($session, 'failed', 'agent_buffer_overflow');
}
};
$target->onMessage = function (AsyncTcpConnection $target, string $data) use ($session, $agentConnection): void {
$session->bytesTargetToClient += strlen($data);

8
src/Transport/KcpFrameClientTransport.php
View File

@ -37,7 +37,7 @@ final class KcpFrameClientTransport implements FrameClientTransport
$this->connection = $connection;
$this->sender = new KcpUdpPacketSender(
$connection,
KcpConfig::int('LAYLINK_KCP_UDP_SEND_QUEUE_BYTES', 16 * 1024 * 1024, 1024 * 1024, 512 * 1024 * 1024),
KcpConfig::int('LAYLINK_KCP_UDP_SEND_QUEUE_BYTES', 64 * 1024 * 1024, 1024 * 1024, 512 * 1024 * 1024),
);
$connection->onConnect = function () use ($connection): void {
@ -130,14 +130,14 @@ final class KcpFrameClientTransport implements FrameClientTransport
'type' => KcpPacketCodec::SYN,
'conv' => $this->conv,
]));
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
return;
}
$before = $this->getSendBufferQueueSize();
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
$this->session?->tick();
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$this->sender?->flush(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
if ($before >= $this->maxSendBuffer && $this->getSendBufferQueueSize() < $this->maxSendBuffer) {
($this->onBufferDrain)($this);
}

70
src/Transport/KcpFrameServerListener.php
View File

@ -15,6 +15,8 @@ final class KcpFrameServerListener
private array $connections = [];
/** @var array<string, KcpReliableSession|NativeKcpSession> */
private array $sessions = [];
/** @var array<int, string> */
private array $keysByConv = [];
private ?int $timerId = null;
private int $nextConnectionId = 1_000_000;
@ -48,6 +50,7 @@ final class KcpFrameServerListener
return;
}
$key = $this->key($connection, $conv);
$key = $this->knownKey($connection, $conv, $key);
$wrapped = $this->connections[$key] ?? null;
$session = $this->sessions[$key] ?? null;
if ($wrapped === null || $session === null) {
@ -72,6 +75,7 @@ final class KcpFrameServerListener
$this->handleSyn($connection, $key, $packet['conv']);
return;
}
$key = $this->knownKey($connection, $packet['conv'], $key);
$wrapped = $this->connections[$key] ?? null;
$session = $this->sessions[$key] ?? null;
@ -98,31 +102,35 @@ final class KcpFrameServerListener
private function handleSyn(UdpConnection $connection, string $key, int $conv): void
{
if (isset($this->keysByConv[$conv]) && $this->keysByConv[$conv] !== $key) {
$key = $this->migrateConnection($this->keysByConv[$conv], $key, $connection, $conv);
}
if (isset($this->connections[$key])) {
$this->connections[$key]->updateConnection($connection);
$this->connections[$key]->sendUdpPacket(KcpPacketCodec::encode([
'type' => KcpPacketCodec::SYN_ACK,
'conv' => $conv,
]));
$this->connections[$key]->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$this->connections[$key]->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
return;
}
$sender = new KcpUdpPacketSender(
$connection,
KcpConfig::int('LAYLINK_KCP_UDP_SEND_QUEUE_BYTES', 16 * 1024 * 1024, 1024 * 1024, 512 * 1024 * 1024),
KcpConfig::int('LAYLINK_KCP_UDP_SEND_QUEUE_BYTES', 64 * 1024 * 1024, 1024 * 1024, 512 * 1024 * 1024),
);
$session = $this->createSession(
$conv,
fn (string $packet): bool|null => $sender->send($packet),
function (Frame $frame) use ($key): void {
$wrapped = $this->connections[$key] ?? null;
function (Frame $frame) use ($conv): void {
$wrapped = $this->connectionForConv($conv);
if ($wrapped !== null) {
($this->onFrame)($wrapped, $frame);
}
},
function (\Throwable $e) use ($key): void {
$wrapped = $this->connections[$key] ?? null;
function (\Throwable $e) use ($conv): void {
$wrapped = $this->connectionForConv($conv);
if ($wrapped !== null) {
($this->onInvalidFrame)($wrapped, $e);
}
@ -131,6 +139,7 @@ final class KcpFrameServerListener
$wrapped = new KcpFrameServerConnection($this->nextConnectionId++, $connection, $session, $sender, $this->maxSendBuffer);
$this->sessions[$key] = $session;
$this->connections[$key] = $wrapped;
$this->keysByConv[$conv] = $key;
$sender->send(KcpPacketCodec::encode([
'type' => KcpPacketCodec::SYN_ACK,
@ -149,9 +158,9 @@ final class KcpFrameServerListener
}
$before = $session->getSendBufferQueueSize();
$wrapped->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$wrapped->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
$session->tick();
$wrapped->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 256, 1, 8192));
$wrapped->flushUdp(KcpConfig::int('LAYLINK_KCP_UDP_FLUSH_PACKETS', 1024, 1, 8192));
if ($before >= $this->maxSendBuffer && $session->getSendBufferQueueSize() < $this->maxSendBuffer) {
($this->onBufferDrain)($wrapped);
}
@ -161,7 +170,11 @@ final class KcpFrameServerListener
private function closeConnection(string $key): void
{
$wrapped = $this->connections[$key] ?? null;
$session = $this->sessions[$key] ?? null;
unset($this->connections[$key], $this->sessions[$key]);
if ($session !== null) {
unset($this->keysByConv[$session->conv()]);
}
if ($wrapped !== null) {
($this->onClose)($wrapped);
}
@ -182,4 +195,45 @@ final class KcpFrameServerListener
{
return $connection->getRemoteAddress() . '#' . $conv;
}
private function knownKey(UdpConnection $connection, int $conv, string $candidate): string
{
if (isset($this->connections[$candidate])) {
return $candidate;
}
$known = $this->keysByConv[$conv] ?? null;
if ($known === null || !isset($this->connections[$known], $this->sessions[$known])) {
return $candidate;
}
return $this->migrateConnection($known, $candidate, $connection, $conv);
}
private function migrateConnection(string $oldKey, string $newKey, UdpConnection $connection, int $conv): string
{
if ($oldKey === $newKey) {
return $newKey;
}
$wrapped = $this->connections[$oldKey] ?? null;
$session = $this->sessions[$oldKey] ?? null;
if ($wrapped === null || $session === null) {
return $newKey;
}
unset($this->connections[$oldKey], $this->sessions[$oldKey]);
$wrapped->updateConnection($connection);
$this->connections[$newKey] = $wrapped;
$this->sessions[$newKey] = $session;
$this->keysByConv[$conv] = $newKey;
return $newKey;
}
private function connectionForConv(int $conv): ?KcpFrameServerConnection
{
$key = $this->keysByConv[$conv] ?? null;
return $key === null ? null : ($this->connections[$key] ?? null);
}
}

1
src/Transport/NativeKcpLibrary.php
View File

@ -22,6 +22,7 @@ final class NativeKcpLibrary
int laylink_kcp_peeksize(laylink_kcp* session);
int laylink_kcp_recv(laylink_kcp* session, char* buffer, int len);
void laylink_kcp_flush(laylink_kcp* session);
int laylink_kcp_waitsnd(laylink_kcp* session);
int laylink_kcp_pending_output_size(laylink_kcp* session);
int laylink_kcp_pop_output(laylink_kcp* session, char* buffer, int len);
CDEF;

25
src/Transport/NativeKcpSession.php
View File

@ -18,9 +18,9 @@ final class NativeKcpSession
private FrameParser $parser;
private bool $paused = false;
private bool $closed = false;
private int $mtuBytes;
/** @var Frame[] */
private array $pausedFrames = [];
private int $queuedBytes = 0;
public function __construct(
private readonly int $conv,
@ -40,17 +40,15 @@ final class NativeKcpSession
KcpConfig::int('LAYLINK_KCP_NODELAY', 1, 0, 1),
KcpConfig::int('LAYLINK_KCP_INTERVAL_MS', 10, 1, 1000),
KcpConfig::int('LAYLINK_KCP_FAST_RESEND', 2, 0, 10),
KcpConfig::int('LAYLINK_KCP_NO_CONGESTION_CONTROL', 0, 0, 1),
KcpConfig::int('LAYLINK_KCP_NO_CONGESTION_CONTROL', 1, 0, 1),
);
$this->ffi->laylink_kcp_wndsize(
$this->session,
KcpConfig::int('LAYLINK_KCP_SEND_WINDOW', 256, 16, 8192),
KcpConfig::int('LAYLINK_KCP_RECV_WINDOW', 512, 16, 8192),
);
$this->ffi->laylink_kcp_setmtu(
$this->session,
KcpConfig::int('LAYLINK_KCP_MTU_BYTES', 1200, 576, 1400),
KcpConfig::int('LAYLINK_KCP_SEND_WINDOW', 1024, 16, 8192),
KcpConfig::int('LAYLINK_KCP_RECV_WINDOW', 1024, 16, 8192),
);
$this->mtuBytes = KcpConfig::int('LAYLINK_KCP_MTU_BYTES', 1350, 576, 1400);
$this->ffi->laylink_kcp_setmtu($this->session, $this->mtuBytes);
$this->parser = new FrameParser();
}
@ -70,7 +68,7 @@ final class NativeKcpSession
public function sendFrame(Frame $frame, int $maxSendBuffer): bool|null
{
if ($this->closed || $this->queuedBytes >= $maxSendBuffer) {
if ($this->closed || $this->getSendBufferQueueSize() >= $maxSendBuffer) {
return false;
}
@ -80,7 +78,6 @@ final class NativeKcpSession
return false;
}
$this->queuedBytes += strlen($bytes);
$this->ffi->laylink_kcp_flush($this->session);
$this->drainOutput();
return true;
@ -146,7 +143,10 @@ final class NativeKcpSession
public function getSendBufferQueueSize(): int
{
return max($this->queuedBytes, $this->pendingOutputBytes());
$waitSegments = $this->ffi->laylink_kcp_waitsnd($this->session);
$waitBytes = max(0, $waitSegments) * $this->mtuBytes;
return $waitBytes + $this->pendingOutputBytes();
}
private function drainFrames(): void
@ -164,7 +164,6 @@ final class NativeKcpSession
return;
}
$this->queuedBytes = max(0, $this->queuedBytes - $read);
$bytes = FFI::string($buffer, $read);
try {
foreach ($this->parser->push($bytes) as $frame) {
@ -183,7 +182,7 @@ final class NativeKcpSession
private function drainOutput(): void
{
$drained = 0;
$maxPackets = KcpConfig::int('LAYLINK_KCP_OUTPUT_DRAIN_PACKETS', 256, 1, 8192);
$maxPackets = KcpConfig::int('LAYLINK_KCP_OUTPUT_DRAIN_PACKETS', 1024, 1, 8192);
while ($drained < $maxPackets && ($size = $this->ffi->laylink_kcp_pending_output_size($this->session)) > 0) {
$buffer = $this->ffi->new("char[$size]");
$read = $this->ffi->laylink_kcp_pop_output($this->session, $buffer, $size);