From ec145b73fc91dd54695dd374c8a71a11e233b8c0 Mon Sep 17 00:00:00 2001 From: Brion Vibber Date: Tue, 12 Jan 2010 19:57:15 -0800 Subject: Major refactoring of queue handlers to support running multiple sites in one daemon. Key changes: * Initialization code moved from common.php to StatusNet class; can now switch configurations during runtime. * As a consequence, configuration files must now be idempotent... Be careful with constant, function or class definitions. * Control structure for daemons/QueueManager/QueueHandler has been refactored; the run loop is now managed by IoMaster run via scripts/queuedaemon.php IoManager subclasses are woken to handle socket input or polling, and may cover multiple sites. * Plugins can implement notice queue handlers more easily by registering a QueueHandler class; no more need to add a daemon. The new QueueDaemon runs from scripts/queuedaemon.php: * This replaces most of the old *handler.php scripts; they've been refactored to the bare handler classes. * Spawns multiple child processes to spread load; defaults to CPU count on Linux and Mac OS X systems, or override with --threads=N * When multithreaded, child processes are automatically respawned on failure. * Threads gracefully shut down and restart when passing a soft memory limit (defaults to 90% of memory_limit), limiting damage from memory leaks. * Support for UDP-based monitoring: http://www.gitorious.org/snqmon Rough control flow diagram: QueueDaemon -> IoMaster -> IoManager QueueManager [listen or poll] -> QueueHandler XmppManager [ping & keepalive] XmppConfirmManager [poll updates] Todo: * Respawning features not currently available running single-threaded. * When running single-site, configuration changes aren't picked up. * New sites or config changes affecting queue subscriptions are not yet handled without a daemon restart. * SNMP monitoring output to integrate with general tools (nagios, ganglia) * Convert XMPP confirmation message sends to use stomp queue instead of polling * Convert xmppdaemon.php to IoManager? * Convert Twitter status, friends import polling daemons to IoManager * Clean up some error reporting and failure modes * May need to adjust queue priorities for best perf in backlog/flood cases Detailed code history available in my daemon-work branch: http://www.gitorious.org/~brion/statusnet/brion-fixes/commits/daemon-work --- classes/Memcached_DataObject.php | 23 +++++++++++++++++++++++ classes/Queue_item.php | 9 ++++++--- classes/Status_network.php | 23 ++++++++++++++++++++--- 3 files changed, 49 insertions(+), 6 deletions(-) (limited to 'classes') diff --git a/classes/Memcached_DataObject.php b/classes/Memcached_DataObject.php index 9c9994cea..4ecab9db6 100644 --- a/classes/Memcached_DataObject.php +++ b/classes/Memcached_DataObject.php @@ -331,6 +331,29 @@ class Memcached_DataObject extends DB_DataObject $exists = false; } + // @fixme horrible evil hack! + // + // In multisite configuration we don't want to keep around a separate + // connection for every database; we could end up with thousands of + // connections open per thread. In an ideal world we might keep + // a connection per server and select different databases, but that'd + // be reliant on having the same db username/pass as well. + // + // MySQL connections are cheap enough we're going to try just + // closing out the old connection and reopening when we encounter + // a new DSN. + // + // WARNING WARNING if we end up actually using multiple DBs at a time + // we'll need some fancier logic here. + if (!$exists && !empty($_DB_DATAOBJECT['CONNECTIONS'])) { + foreach ($_DB_DATAOBJECT['CONNECTIONS'] as $index => $conn) { + if (!empty($conn)) { + $conn->disconnect(); + } + unset($_DB_DATAOBJECT['CONNECTIONS'][$index]); + } + } + $result = parent::_connect(); if ($result && !$exists) { diff --git a/classes/Queue_item.php b/classes/Queue_item.php index 9c673540d..cf805a606 100644 --- a/classes/Queue_item.php +++ b/classes/Queue_item.php @@ -25,10 +25,12 @@ class Queue_item extends Memcached_DataObject function sequenceKey() { return array(false, false); } - static function top($transport) { + static function top($transport=null) { $qi = new Queue_item(); - $qi->transport = $transport; + if ($transport) { + $qi->transport = $transport; + } $qi->orderBy('created'); $qi->whereAdd('claimed is null'); @@ -40,7 +42,8 @@ class Queue_item extends Memcached_DataObject # XXX: potential race condition # can we force it to only update if claimed is still null # (or old)? - common_log(LOG_INFO, 'claiming queue item = ' . $qi->notice_id . ' for transport ' . $transport); + common_log(LOG_INFO, 'claiming queue item = ' . $qi->notice_id . + ' for transport ' . $qi->transport); $orig = clone($qi); $qi->claimed = common_sql_now(); $result = $qi->update($orig); diff --git a/classes/Status_network.php b/classes/Status_network.php index 776f6abb0..ef8e1ed43 100644 --- a/classes/Status_network.php +++ b/classes/Status_network.php @@ -49,6 +49,13 @@ class Status_network extends DB_DataObject static $cache = null; static $base = null; + /** + * @param string $dbhost + * @param string $dbuser + * @param string $dbpass + * @param string $dbname + * @param array $servers memcached servers to use for caching config info + */ static function setupDB($dbhost, $dbuser, $dbpass, $dbname, $servers) { global $config; @@ -60,12 +67,17 @@ class Status_network extends DB_DataObject if (class_exists('Memcache')) { self::$cache = new Memcache(); + // Can't close persistent connections, making forking painful. + // + // @fixme only do this in *parent* CLI processes. + // single-process and child-processes *should* use persistent. + $persist = php_sapi_name() != 'cli'; if (is_array($servers)) { foreach($servers as $server) { - self::$cache->addServer($server); + self::$cache->addServer($server, 11211, $persist); } } else { - self::$cache->addServer($servers); + self::$cache->addServer($servers, 11211, $persist); } } @@ -89,7 +101,7 @@ class Status_network extends DB_DataObject if (empty($sn)) { $sn = self::staticGet($k, $v); if (!empty($sn)) { - self::$cache->set($ck, $sn); + self::$cache->set($ck, clone($sn)); } } @@ -121,6 +133,11 @@ class Status_network extends DB_DataObject return parent::delete(); } + /** + * @param string $servername hostname + * @param string $pathname URL base path + * @param string $wildcard hostname suffix to match wildcard config + */ static function setupSite($servername, $pathname, $wildcard) { global $config; -- cgit v1.2.3-54-g00ecf