优化3

.env.example

@@ -9,6 +9,12 @@ LAYLINK_FRAME_ENCRYPTION=none
 # Agent 与 POP Server 之间 Frame 加密方式；可选 none、chacha20，两端必须一致。
 LAYLINK_FRAME_ENCRYPTION_KEY=
 # Frame 加密密钥；LAYLINK_FRAME_ENCRYPTION=chacha20 时必填。可填普通口令，或 hex:32字节十六进制，或 base64:32字节base64。
+LAYLINK_DATA_CHUNK_BYTES=1048576
+# TCP DATA 帧分片大小；单位字节。较大值可减少帧数量并提升吞吐，建议 262144、524288、1048576、2097152。
+LAYLINK_MAX_SEND_BUFFER_BYTES=67108864
+# 单连接发送缓冲区上限；单位字节。大文件下载建议 33554432 或 67108864，内存紧张时调小。
+LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES=33554432
+# 背压触发水位；单位字节。应小于 LAYLINK_MAX_SEND_BUFFER_BYTES，达到后会暂停上游读取直到缓冲排空。
 
 [client-agent]
 NODE_ID=client-01

bin/client-agent.php

@@ -39,6 +39,9 @@ $bootAgent = function (string $protocol, string $listen, string $name) use ($nod
             ? Env::get('CLIENT_AGENT_SOCKS5_UDP_LISTEN_IP', '127.0.0.1') . ':' . Env::get('CLIENT_AGENT_SOCKS5_UDP_LISTEN_PORT', '1081')
             : null,
         Env::get('CLIENT_AGENT_SOCKS5_UDP_ADVERTISE_IP', Env::get('CLIENT_AGENT_SOCKS5_LISTEN_IP', '127.0.0.1')),
+        Env::int('LAYLINK_MAX_SEND_BUFFER_BYTES', 64 * 1024 * 1024, 1024 * 1024),
+        Env::int('LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES', 32 * 1024 * 1024, 512 * 1024),
+        Env::int('LAYLINK_DATA_CHUNK_BYTES', 1024 * 1024, 16 * 1024, 8 * 1024 * 1024),
     );
     $agent->boot($name);
 };

bin/pop-server.php

@@ -24,6 +24,9 @@ $server = new PopServer(
     require dirname(__DIR__) . '/config/policies.php',
     Env::csv('POP_ALLOWED_AGENT_TRANSPORTS', ['tcp']),
     Env::get('AUDIT_LOG', dirname(__DIR__) . '/runtime/audit.log'),
+    Env::int('LAYLINK_MAX_SEND_BUFFER_BYTES', 64 * 1024 * 1024, 1024 * 1024),
+    Env::int('LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES', 32 * 1024 * 1024, 512 * 1024),
+    Env::int('LAYLINK_DATA_CHUNK_BYTES', 1024 * 1024, 16 * 1024, 8 * 1024 * 1024),
 );
 $server->boot();
 

contract.md

@@ -168,10 +168,14 @@ Completed in this checkpoint:
   * POP resumes target reads when the Agent connection drains.
   * Client Agent pauses local client reads when the POP connection send buffer crosses the high watermark.
   * Client Agent pauses POP reads while a local client output buffer is full.
-  * Send buffer limits are raised to 32 MiB with a 16 MiB backpressure high watermark.
+  * Send buffer limits default to 64 MiB with a 32 MiB backpressure high watermark.
+  * Tuning envs:
+    * `LAYLINK_DATA_CHUNK_BYTES`
+    * `LAYLINK_MAX_SEND_BUFFER_BYTES`
+    * `LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES`
 * Fixed large-download truncation risk:
   * Client Agent now treats POP `CLOSE` as a graceful remote EOF and waits for the local client send buffer to drain before closing the local socket.
-  * TCP `DATA` is split into 256 KiB chunks to avoid oversized frames and improve fairness between sessions.
+  * TCP `DATA` is split into configurable chunks, defaulting to 1 MiB, to reduce frame overhead while avoiding oversized frames.
   * POP refreshes Agent activity on any valid frame, not only `PING`, reducing heartbeat false positives during heavy traffic.
 
 Known MVP limitations:

readme.md

@@ -380,9 +380,19 @@ php bin/client-agent.php start
 
 TCP 大流量 `DATA` 帧使用二进制帧编码；`AUTH`、`OPEN`、`CLOSE`、`ERROR` 等控制帧仍使用 JSON 编码。启用 `chacha20` 时，二进制和 JSON Frame body 都会被加密。
 
+吞吐相关参数由两端共用，POP Server 和 Client Agent 建议保持一致：
+
+```env
+LAYLINK_DATA_CHUNK_BYTES=1048576
+LAYLINK_MAX_SEND_BUFFER_BYTES=67108864
+LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES=33554432
+```
+
+`LAYLINK_DATA_CHUNK_BYTES` 越大，每 MB 需要处理的 Frame 越少，单连接下载通常越快；如果多会话公平性变差，可以降到 `262144` 或 `524288`。`LAYLINK_BACKPRESSURE_HIGH_WATERMARK_BYTES` 必须小于 `LAYLINK_MAX_SEND_BUFFER_BYTES`。
+
 大文件下载时，LayLink 会使用 Workerman 的 `pauseRecv()` / `resumeRecv()` 做背压：当下游发送缓冲区过高时暂停上游读取，缓冲排空后继续读取。这可以避免单个慢连接无限堆积内存或因为发送缓冲区满而断联。
 
-当 POP 收到目标站关闭连接时，Client Agent 会先等待本地客户端发送缓冲区排空，再关闭本地 socket，避免大文件尾部数据还在缓冲区里时被提前截断。TCP `DATA` 会按 256 KiB 分片发送，以避免巨帧并改善多会话公平性。
+当 POP 收到目标站关闭连接时，Client Agent 会先等待本地客户端发送缓冲区排空，再关闭本地 socket，避免大文件尾部数据还在缓冲区里时被提前截断。TCP `DATA` 默认按 1 MiB 分片发送，以减少帧开销；可通过 `LAYLINK_DATA_CHUNK_BYTES` 调整。
 
 当前每个 Client Agent worker 仍然通过单条 Agent-to-POP TCP 长连接承载多个会话。背压可以保护进程不堵死，但单条 TCP 长连接仍可能产生队头阻塞；多 worker、多 POP 长连接、KCP 或 per-session window 是后续性能优化方向。
 

src/Agent/AgentClient.php

@@ -17,10 +17,6 @@ use Workerman\Worker;
 
 final class AgentClient
 {
-    private const MAX_SEND_BUFFER = 32 * 1024 * 1024;
-    private const BACKPRESSURE_HIGH_WATERMARK = 16 * 1024 * 1024;
-    private const DATA_CHUNK_SIZE = 256 * 1024;
-
     private ?AsyncTcpConnection $pop = null;
     private ?FrameParser $parser = null;
     private bool $authenticated = false;
@@ -67,6 +63,9 @@ final class AgentClient
         private readonly string $socks5Password = '',
         private readonly ?string $socks5UdpListen = null,
         private readonly string $socks5UdpAdvertiseIp = '127.0.0.1',
+        private readonly int $maxSendBuffer = 64 * 1024 * 1024,
+        private readonly int $backpressureHighWatermark = 32 * 1024 * 1024,
+        private readonly int $dataChunkSize = 1024 * 1024,
     ) {
     }
 
@@ -99,7 +98,7 @@ final class AgentClient
         $this->parser = new FrameParser();
         $this->authenticated = false;
         $connection = new AsyncTcpConnection($this->popAddress);
-        $connection->maxSendBufferSize = self::MAX_SEND_BUFFER;
+        $connection->maxSendBufferSize = $this->maxSendBuffer;
         $this->pop = $connection;
 
         $connection->onConnect = function (AsyncTcpConnection $connection): void {
@@ -161,7 +160,7 @@ final class AgentClient
 
     private function onClientConnect(TcpConnection $connection): void
     {
-        $connection->maxSendBufferSize = self::MAX_SEND_BUFFER;
+        $connection->maxSendBufferSize = $this->maxSendBuffer;
         $connection->onBufferFull = fn (TcpConnection $connection) => $this->pausePopForClient($connection);
         $connection->onBufferDrain = fn (TcpConnection $connection) => $this->onClientBufferDrain($connection);
         $this->initialBuffers[$connection->id] = '';
@@ -185,7 +184,7 @@ final class AgentClient
             $this->closeClient($sessionId);
             return;
         }
-        if ($this->pop !== null && $this->pop->getSendBufferQueueSize() >= self::BACKPRESSURE_HIGH_WATERMARK) {
+        if ($this->pop !== null && $this->pop->getSendBufferQueueSize() >= $this->backpressureHighWatermark) {
             $connection->pauseRecv();
             $this->pausedClientsForPop[$connection->id] = $connection;
         }
@@ -611,7 +610,7 @@ final class AgentClient
             $this->closeClient($frame->sessionId);
             return;
         }
-        if ($client->getSendBufferQueueSize() >= self::BACKPRESSURE_HIGH_WATERMARK) {
+        if ($client->getSendBufferQueueSize() >= $this->backpressureHighWatermark) {
             $this->pausePopForClient($client);
         }
     }
@@ -833,9 +832,9 @@ final class AgentClient
     private function sendData(string $sessionId, string $data): bool
     {
         $length = strlen($data);
-        for ($offset = 0; $offset < $length; $offset += self::DATA_CHUNK_SIZE) {
+        for ($offset = 0; $offset < $length; $offset += $this->dataChunkSize) {
             $sent = $this->send(new Frame(FrameType::DATA, $sessionId, [
-                'data_raw' => substr($data, $offset, self::DATA_CHUNK_SIZE),
+                'data_raw' => substr($data, $offset, $this->dataChunkSize),
             ]));
             if ($sent === false) {
                 return false;

src/Server/AgentListener.php

@@ -24,10 +24,6 @@ use Workerman\Worker;
 
 final class AgentListener
 {
-    private const MAX_SEND_BUFFER = 32 * 1024 * 1024;
-    private const BACKPRESSURE_HIGH_WATERMARK = 16 * 1024 * 1024;
-    private const DATA_CHUNK_SIZE = 256 * 1024;
-
     /** @var array<int, FrameParser> */
     private array $parsers = [];
     /** @var array<int, string> */
@@ -43,6 +39,9 @@ final class AgentListener
         private readonly NodeRegistry $nodes,
         private readonly SessionManager $sessions,
         private readonly AuditLogger $audit,
+        private readonly int $maxSendBuffer = 64 * 1024 * 1024,
+        private readonly int $backpressureHighWatermark = 32 * 1024 * 1024,
+        private readonly int $dataChunkSize = 1024 * 1024,
     ) {
         $worker->onConnect = fn (TcpConnection $connection) => $this->onConnect($connection);
         $worker->onMessage = fn (TcpConnection $connection, string $data) => $this->onMessage($connection, $data);
@@ -52,7 +51,7 @@ final class AgentListener
 
     private function onConnect(TcpConnection $connection): void
     {
-        $connection->maxSendBufferSize = self::MAX_SEND_BUFFER;
+        $connection->maxSendBufferSize = $this->maxSendBuffer;
         $connection->onBufferDrain = fn (TcpConnection $connection) => $this->resumeTargetsForAgent($connection);
         $this->parsers[$connection->id] = new FrameParser();
     }
@@ -231,7 +230,7 @@ final class AgentListener
         $this->sessions->add($session);
 
         $target = new AsyncTcpConnection($targetAddress);
-        $target->maxSendBufferSize = self::MAX_SEND_BUFFER;
+        $target->maxSendBufferSize = $this->maxSendBuffer;
         $session->target = $target;
 
         $target->onConnect = function () use ($session, $agentConnection): void {
@@ -247,7 +246,7 @@ final class AgentListener
                 $this->closeSession($session, 'failed', 'agent_buffer_overflow');
                 return;
             }
-            if ($agentConnection->getSendBufferQueueSize() >= self::BACKPRESSURE_HIGH_WATERMARK) {
+            if ($agentConnection->getSendBufferQueueSize() >= $this->backpressureHighWatermark) {
                 $target->pauseRecv();
                 $this->pausedTargetsByAgent[$agentConnection->id][$session->sessionId] = $target;
             }
@@ -275,7 +274,7 @@ final class AgentListener
             $this->closeSession($session, 'failed', 'target_buffer_overflow');
             return;
         }
-        if ($session->target->getSendBufferQueueSize() >= self::BACKPRESSURE_HIGH_WATERMARK && $session->agent !== null) {
+        if ($session->target->getSendBufferQueueSize() >= $this->backpressureHighWatermark && $session->agent !== null) {
             $session->agent->pauseRecv();
             $session->target->onBufferDrain = function (AsyncTcpConnection $target) use ($session): void {
                 $session->agent?->resumeRecv();
@@ -395,9 +394,9 @@ final class AgentListener
     private function sendData(TcpConnection $connection, string $sessionId, string $data): bool
     {
         $length = strlen($data);
-        for ($offset = 0; $offset < $length; $offset += self::DATA_CHUNK_SIZE) {
+        for ($offset = 0; $offset < $length; $offset += $this->dataChunkSize) {
             $sent = $this->send($connection, new Frame(FrameType::DATA, $sessionId, [
-                'data_raw' => substr($data, $offset, self::DATA_CHUNK_SIZE),
+                'data_raw' => substr($data, $offset, $this->dataChunkSize),
             ]));
             if ($sent === false) {
                 return false;

src/Server/PopServer.php

@@ -25,6 +25,9 @@ final class PopServer
         private readonly array $policies,
         private readonly array $allowedAgentTransports,
         string $auditLog,
+        private readonly int $maxSendBuffer = 64 * 1024 * 1024,
+        private readonly int $backpressureHighWatermark = 32 * 1024 * 1024,
+        private readonly int $dataChunkSize = 1024 * 1024,
     ) {
         $this->nodes = new NodeRegistry();
         $this->sessions = new SessionManager();
@@ -44,6 +47,9 @@ final class PopServer
             $this->nodes,
             $this->sessions,
             $this->audit,
+            $this->maxSendBuffer,
+            $this->backpressureHighWatermark,
+            $this->dataChunkSize,
         );
     }
 }

src/Util/Env.php

@@ -49,6 +49,21 @@ final class Env
         return in_array(strtolower(trim($value)), ['1', 'true', 'yes', 'on'], true);
     }
 
+    public static function int(string $key, int $default, int $min = PHP_INT_MIN, int $max = PHP_INT_MAX): int
+    {
+        $value = getenv($key);
+        if ($value === false || trim($value) === '') {
+            return $default;
+        }
+
+        $value = trim($value);
+        if (!preg_match('/^-?\d+$/', $value)) {
+            return $default;
+        }
+
+        return max($min, min($max, (int)$value));
+    }
+
     /**
      * @return string[]
      */