gnu-social/lib/iomaster.php
Brion Vibber ce6be4f836 Queues: redid the breakout control model so we can start up and subscribe to queues without running through the complete site list, which is ok at 1k sites but too slow at 10k.
All breakout queues that we're going to need to listen to now need to be explicitly listed in $config['queue']['breakout'].

Until XMPP is moved to component model, this setting will let the individual processes work with their own queues:
$config['queue']['breakout'][] = 'xmpp/xmppout/' . $config['site']['nickname'];
2010-02-17 16:49:00 -08:00

361 lines
11 KiB
PHP

<?php
/**
* StatusNet, the distributed open-source microblogging tool
*
* I/O manager to wrap around socket-reading and polling queue & connection managers.
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category QueueManager
* @package StatusNet
* @author Brion Vibber <brion@status.net>
* @copyright 2009 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
abstract class IoMaster
{
public $id;
protected $multiSite = false;
protected $managers = array();
protected $singletons = array();
protected $pollTimeouts = array();
protected $lastPoll = array();
public $shutdown = false; // Did we do a graceful shutdown?
public $respawn = true; // Should we respawn after shutdown?
/**
* @param string $id process ID to use in logging/monitoring
*/
public function __construct($id)
{
$this->id = $id;
$this->monitor = new QueueMonitor();
}
public function init($multiSite=null)
{
if ($multiSite !== null) {
$this->multiSite = $multiSite;
}
$this->initManagers();
}
/**
* Initialize IoManagers which are appropriate to this instance;
* pass class names or instances into $this->instantiate().
*
* If setup and configuration may vary between sites in multi-site
* mode, it's the subclass's responsibility to set them up here.
*
* Switching site configurations is an acceptable side effect.
*/
abstract function initManagers();
/**
* Instantiate an i/o manager class for the current site.
* If a multi-site capable handler is already present,
* we don't need to build a new one.
*
* @param mixed $manager class name (to run $class::get()) or object
*/
protected function instantiate($manager)
{
if (is_string($manager)) {
$manager = call_user_func(array($class, 'get'));
}
$caps = $manager->multiSite();
if ($caps == IoManager::SINGLE_ONLY) {
if ($this->multiSite) {
throw new Exception("$class can't run with --all; aborting.");
}
} else if ($caps == IoManager::INSTANCE_PER_PROCESS) {
$manager->addSite();
}
if (!in_array($manager, $this->managers, true)) {
// Only need to save singletons once
$this->managers[] = $manager;
}
}
/**
* Basic run loop...
*
* Initialize all io managers, then sit around waiting for input.
* Between events or timeouts, pass control back to idle() method
* to allow for any additional background processing.
*/
function service()
{
$this->logState('init');
$this->start();
$this->checkMemory(false);
while (!$this->shutdown) {
$timeouts = array_values($this->pollTimeouts);
$timeouts[] = 60; // default max timeout
// Wait for something on one of our sockets
$sockets = array();
$managers = array();
foreach ($this->managers as $manager) {
foreach ($manager->getSockets() as $socket) {
$sockets[] = $socket;
$managers[] = $manager;
}
$timeouts[] = intval($manager->timeout());
}
$timeout = min($timeouts);
if ($sockets) {
$read = $sockets;
$write = array();
$except = array();
$this->logState('listening');
common_log(LOG_DEBUG, "Waiting up to $timeout seconds for socket data...");
$ready = stream_select($read, $write, $except, $timeout, 0);
if ($ready === false) {
common_log(LOG_ERR, "Error selecting on sockets");
} else if ($ready > 0) {
foreach ($read as $socket) {
$index = array_search($socket, $sockets, true);
if ($index !== false) {
$this->logState('queue');
$managers[$index]->handleInput($socket);
} else {
common_log(LOG_ERR, "Saw input on a socket we didn't listen to");
}
}
}
}
if ($timeout > 0 && empty($sockets)) {
// If we had no listeners, sleep until the pollers' next requested wakeup.
common_log(LOG_DEBUG, "Sleeping $timeout seconds until next poll cycle...");
$this->logState('sleep');
sleep($timeout);
}
$this->logState('poll');
$this->poll();
$this->logState('idle');
$this->idle();
$this->checkMemory();
}
$this->logState('shutdown');
$this->finish();
}
/**
* Check runtime memory usage, possibly triggering a graceful shutdown
* and thread respawn if we've crossed the soft limit.
*
* @param boolean $respawn if false we'll shut down instead of respawning
*/
protected function checkMemory($respawn=true)
{
$memoryLimit = $this->softMemoryLimit();
if ($memoryLimit > 0) {
$usage = memory_get_usage();
if ($usage > $memoryLimit) {
common_log(LOG_INFO, "Queue thread hit soft memory limit ($usage > $memoryLimit); gracefully restarting.");
if ($respawn) {
$this->requestRestart();
} else {
$this->requestShutdown();
}
} else if (common_config('queue', 'debug_memory')) {
$fmt = number_format($usage);
common_log(LOG_DEBUG, "Memory usage $fmt");
}
}
}
/**
* Return fully-parsed soft memory limit in bytes.
* @return intval 0 or -1 if not set
*/
function softMemoryLimit()
{
$softLimit = trim(common_config('queue', 'softlimit'));
if (substr($softLimit, -1) == '%') {
$limit = $this->parseMemoryLimit(ini_get('memory_limit'));
if ($limit > 0) {
return intval(substr($softLimit, 0, -1) * $limit / 100);
} else {
return -1;
}
} else {
return $this->parseMemoryLimit($softLimit);
}
return $softLimit;
}
/**
* Interpret PHP shorthand for memory_limit and friends.
* Why don't they just expose the actual numeric value? :P
* @param string $mem
* @return int
*/
public function parseMemoryLimit($mem)
{
// http://www.php.net/manual/en/faq.using.php#faq.using.shorthandbytes
$mem = strtolower(trim($mem));
$size = array('k' => 1024,
'm' => 1024*1024,
'g' => 1024*1024*1024);
if (empty($mem)) {
return 0;
} else if (is_numeric($mem)) {
return intval($mem);
} else {
$mult = substr($mem, -1);
if (isset($size[$mult])) {
return substr($mem, 0, -1) * $size[$mult];
} else {
return intval($mem);
}
}
}
function start()
{
foreach ($this->managers as $index => $manager) {
$manager->start($this);
// @fixme error check
if ($manager->pollInterval()) {
// We'll want to check for input on the first pass
$this->pollTimeouts[$index] = 0;
$this->lastPoll[$index] = 0;
}
}
}
function finish()
{
foreach ($this->managers as $manager) {
$manager->finish();
// @fixme error check
}
}
/**
* Called during the idle portion of the runloop to see which handlers
*/
function poll()
{
foreach ($this->managers as $index => $manager) {
$interval = $manager->pollInterval();
if ($interval <= 0) {
// Not a polling manager.
continue;
}
if (isset($this->pollTimeouts[$index])) {
$timeout = $this->pollTimeouts[$index];
if (time() - $this->lastPoll[$index] < $timeout) {
// Not time to poll yet.
continue;
}
} else {
$timeout = 0;
}
$hit = $manager->poll();
$this->lastPoll[$index] = time();
if ($hit) {
// Do the next poll quickly, there may be more input!
$this->pollTimeouts[$index] = 0;
} else {
// Empty queue. Exponential backoff up to the maximum poll interval.
if ($timeout > 0) {
$timeout = min($timeout * 2, $interval);
} else {
$timeout = 1;
}
$this->pollTimeouts[$index] = $timeout;
}
}
}
/**
* Called after each handled item or empty polling cycle.
* This is a good time to e.g. service your XMPP connection.
*/
function idle()
{
foreach ($this->managers as $manager) {
$manager->idle();
}
}
/**
* Send thread state update to the monitoring server, if configured.
*
* @param string $state ('init', 'queue', 'shutdown' etc)
* @param string $substate (optional, eg queue name 'omb' 'sms' etc)
*/
protected function logState($state, $substate='')
{
$this->monitor->logState($this->id, $state, $substate);
}
/**
* Send thread stats.
* Thread ID will be implicit; other owners can be listed as well
* for per-queue and per-site records.
*
* @param string $key counter name
* @param array $owners list of owner keys like 'queue:jabber' or 'site:stat01'
*/
public function stats($key, $owners=array())
{
$owners[] = "thread:" . $this->id;
$this->monitor->stats($key, $owners);
}
/**
* For IoManagers to request a graceful shutdown at end of event loop.
*/
public function requestShutdown()
{
$this->shutdown = true;
$this->respawn = false;
}
/**
* For IoManagers to request a graceful restart at end of event loop.
*/
public function requestRestart()
{
$this->shutdown = true;
$this->respawn = true;
}
}