While loop speed in websocket php server - php

Question

I am using the following websocket php class as my server: PHPWebSocket. It works well in every way I could have hoped for, but I've run into a bit of a problem.
I want to update the positions of connected clients (they can walk around) at a rate of maybe every 0.3 seconds. I figured it would be a simple matter of looking for the while loop and adding a heartbeat event there, but here it becomes tricky.
// server state functions
function wsStartServer($host, $port) {
if (isset($this->wsRead[0])) return false;
if (!$this->wsRead[0] = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) {
return false;
}
if (!socket_set_option($this->wsRead[0], SOL_SOCKET, SO_REUSEADDR, 1)) {
socket_close($this->wsRead[0]);
return false;
}
if (!socket_bind($this->wsRead[0], $host, $port)) {
socket_close($this->wsRead[0]);
return false;
}
if (!socket_listen($this->wsRead[0], 10)) {
socket_close($this->wsRead[0]);
return false;
}
$this->log("Server starting");
$write = array();
$except = array();
$nextPingCheck = time() + 1;
while (isset($this->wsRead[0])) {
$changed = $this->wsRead;
$result = socket_select($changed, $write, $except, 1);
**beat()**
if ($result === false) {
socket_close($this->wsRead[0]);
return false;
}
elseif ($result > 0) {
foreach ($changed as $clientID => $socket) {
if ($clientID != 0) {
// client socket changed
$buffer = '';
$bytes = #socket_recv($socket, $buffer, 4096, 0);
if ($bytes === false) {
// error on recv, remove client socket (will check to send close frame)
$this->wsSendClientClose($clientID, self::WS_STATUS_PROTOCOL_ERROR);
}
elseif ($bytes > 0) {
// process handshake or frame(s)
if (!$this->wsProcessClient($clientID, $buffer, $bytes)) {
$this->wsSendClientClose($clientID, self::WS_STATUS_PROTOCOL_ERROR);
}
}
else {
// 0 bytes received from client, meaning the client closed the TCP connection
$this->wsRemoveClient($clientID);
}
}
else {
// listen socket changed
$client = socket_accept($this->wsRead[0]);
if ($client !== false) {
// fetch client IP as integer
$clientIP = '';
$result = socket_getpeername($client, $clientIP);
$clientIP = ip2long($clientIP);
if ($result !== false && $this->wsClientCount < self::WS_MAX_CLIENTS && (!isset($this->wsClientIPCount[$clientIP]) || $this->wsClientIPCount[$clientIP] < self::WS_MAX_CLIENTS_PER_IP)) {
$this->wsAddClient($client, $clientIP);
}
else {
socket_close($client);
}
}
}
}
}
if (time() >= $nextPingCheck) {
$this->wsCheckIdleClients();
$nextPingCheck = time() + 1;
}
}
return true; // returned when wsStopServer() is called
}
To me it doesn't seem like there is any specific timer that says it should only run once per second, but it does. I am not talking about the ping check, even if I place my heartbeat call directly after the while (isset($this->wsRead[0])) {, it will only trigger once per second, and it has me completely stumped.
Am I looking in the wrong place? Is there something about PHP's websocket implementation that slows down this while loop?

Answer 1

You have a one second timeout in your socket_select call - that's probably where your delay is introduced. If you want that call to be non-blocking, you can pass a zero for that timeout.