diff --git a/boot.php b/boot.php
index cd6db384a2..ef787c6353 100644
--- a/boot.php
+++ b/boot.php
@@ -19,6 +19,8 @@
 
 require_once('include/autoloader.php');
 
+use \Friendica\Core\Config;
+
 require_once('include/config.php');
 require_once('include/network.php');
 require_once('include/plugin.php');
@@ -38,7 +40,7 @@ define ( 'FRIENDICA_PLATFORM',     'Friendica');
 define ( 'FRIENDICA_CODENAME',     'Asparagus');
 define ( 'FRIENDICA_VERSION',      '3.5.1-dev' );
 define ( 'DFRN_PROTOCOL_VERSION',  '2.23'    );
-define ( 'DB_UPDATE_VERSION',      1212      );
+define ( 'DB_UPDATE_VERSION',      1213      );
 
 /**
  * @brief Constant with a HTML line break.
@@ -823,24 +825,22 @@ class App {
 
 		$scheme = $this->scheme;
 
-		if ((x($this->config, 'system')) && (x($this->config['system'], 'ssl_policy'))) {
-			if (intval($this->config['system']['ssl_policy']) === SSL_POLICY_FULL) {
+		if (Config::get('system', 'ssl_policy') === SSL_POLICY_FULL) {
+			$scheme = 'https';
+		}
+
+		//	Basically, we have $ssl = true on any links which can only be seen by a logged in user
+		//	(and also the login link). Anything seen by an outsider will have it turned off.
+
+		if (Config::get('system', 'ssl_policy') == SSL_POLICY_SELFSIGN) {
+			if ($ssl) {
 				$scheme = 'https';
-			}
-
-			//	Basically, we have $ssl = true on any links which can only be seen by a logged in user
-			//	(and also the login link). Anything seen by an outsider will have it turned off.
-
-			if ($this->config['system']['ssl_policy'] == SSL_POLICY_SELFSIGN) {
-				if ($ssl) {
-					$scheme = 'https';
-				} else {
-					$scheme = 'http';
-				}
+			} else {
+				$scheme = 'http';
 			}
 		}
 
-		if (get_config('config', 'hostname') != '') {
+		if (Config::get('config', 'hostname') != '') {
 			$this->hostname = get_config('config', 'hostname');
 		}
 
@@ -1391,11 +1391,15 @@ class App {
 			// If the last worker fork was less than 10 seconds before then don't fork another one.
 			// This should prevent the forking of masses of workers.
 			if (get_config("system", "worker")) {
-				if ((time() - get_config("system", "proc_run_started")) < 10)
-					return;
-
+				$cachekey = "app:proc_run:started";
+				$result = Cache::get($cachekey);
+				if (!is_null($result)) {
+					if ((time() - $result) < 10) {
+						return;
+					}
+				}
 				// Set the timestamp of the last proc_run
-				set_config("system", "proc_run_started", time());
+				Cache::set($cachekey, time(), CACHE_MINUTE);
 			}
 
 			$args[0] = ((x($this->config,'php_path')) && (strlen($this->config['php_path'])) ? $this->config['php_path'] : 'php');
@@ -1475,9 +1479,7 @@ function system_unavailable() {
 
 function clean_urls() {
 	$a = get_app();
-	//	if($a->config['system']['clean_urls'])
 	return true;
-	//	return false;
 }
 
 function z_path() {
@@ -1571,7 +1573,7 @@ function update_db(App $a) {
 		$stored = intval($build);
 		$current = intval(DB_UPDATE_VERSION);
 		if($stored < $current) {
-			load_config('database');
+			Config::load('database');
 
 			// We're reporting a different version than what is currently installed.
 			// Run any existing update scripts to bring the database up to current.
@@ -2041,16 +2043,18 @@ function current_theme(){
 //		$is_mobile = $mobile_detect->isMobile() || $mobile_detect->isTablet();
 	$is_mobile = $a->is_mobile || $a->is_tablet;
 
-	$standard_system_theme = ((isset($a->config['system']['theme'])) ? $a->config['system']['theme'] : '');
+	$standard_system_theme = Config::get('system', 'theme', '');
 	$standard_theme_name = ((isset($_SESSION) && x($_SESSION,'theme')) ? $_SESSION['theme'] : $standard_system_theme);
 
-	if($is_mobile) {
-		if(isset($_SESSION['show-mobile']) && !$_SESSION['show-mobile']) {
+	if ($is_mobile) {
+		if (isset($_SESSION['show-mobile']) && !$_SESSION['show-mobile']) {
 			$system_theme = $standard_system_theme;
 			$theme_name = $standard_theme_name;
-		}
-		else {
-			$system_theme = ((isset($a->config['system']['mobile-theme'])) ? $a->config['system']['mobile-theme'] : $standard_system_theme);
+		} else {
+			$system_theme = Config::get('system', 'mobile-theme', '');
+			if ($system_theme == '') {
+				$system_theme = $standard_system_theme;
+			}
 			$theme_name = ((isset($_SESSION) && x($_SESSION,'mobile-theme')) ? $_SESSION['mobile-theme'] : $system_theme);
 
 			if($theme_name === '---') {
diff --git a/database.sql b/database.sql
index becd14fc73..64d8d9f7d0 100644
--- a/database.sql
+++ b/database.sql
@@ -1,6 +1,6 @@
 -- ------------------------------------------
 -- Friendica 3.5.1-dev (Asparagus)
--- DB_UPDATE_VERSION 1212
+-- DB_UPDATE_VERSION 1213
 -- ------------------------------------------
 
 
@@ -9,13 +9,14 @@
 --
 CREATE TABLE IF NOT EXISTS `addon` (
 	`id` int(11) NOT NULL auto_increment,
-	`name` varchar(255) NOT NULL DEFAULT '',
+	`name` varchar(190) NOT NULL DEFAULT '',
 	`version` varchar(255) NOT NULL DEFAULT '',
 	`installed` tinyint(1) NOT NULL DEFAULT 0,
 	`hidden` tinyint(1) NOT NULL DEFAULT 0,
 	`timestamp` bigint(20) NOT NULL DEFAULT 0,
 	`plugin_admin` tinyint(1) NOT NULL DEFAULT 0,
-	 PRIMARY KEY(`id`)
+	 PRIMARY KEY(`id`),
+	 UNIQUE INDEX `name` (`name`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -55,11 +56,10 @@ CREATE TABLE IF NOT EXISTS `auth_codes` (
 --
 CREATE TABLE IF NOT EXISTS `cache` (
 	`k` varbinary(255) NOT NULL,
-	`v` text,
+	`v` mediumtext,
 	`expire_mode` int(11) NOT NULL DEFAULT 0,
 	`updated` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`k`),
-	 INDEX `updated` (`updated`),
 	 INDEX `expire_mode_updated` (`expire_mode`,`updated`)
 ) DEFAULT CHARSET=utf8mb4;
 
@@ -96,7 +96,7 @@ CREATE TABLE IF NOT EXISTS `config` (
 	`id` int(10) unsigned NOT NULL auto_increment,
 	`cat` varbinary(255) NOT NULL DEFAULT '',
 	`k` varbinary(255) NOT NULL DEFAULT '',
-	`v` text,
+	`v` mediumtext,
 	 PRIMARY KEY(`id`),
 	 UNIQUE INDEX `cat_k` (`cat`,`k`)
 ) DEFAULT CHARSET=utf8mb4;
@@ -172,18 +172,20 @@ CREATE TABLE IF NOT EXISTS `contact` (
 	`bd` date NOT NULL DEFAULT '0000-00-00',
 	`notify_new_posts` tinyint(1) NOT NULL DEFAULT 0,
 	`fetch_further_information` tinyint(1) NOT NULL DEFAULT 0,
-	`ffi_keyword_blacklist` mediumtext,
+	`ffi_keyword_blacklist` text,
 	 PRIMARY KEY(`id`),
 	 INDEX `uid_name` (`uid`,`name`),
-	 INDEX `uid_self` (`uid`,`self`),
+	 INDEX `self_uid` (`self`,`uid`),
 	 INDEX `alias_uid` (`alias`(32),`uid`),
-	 INDEX `uid_pending` (`uid`,`pending`),
-	 INDEX `uid_blocked` (`uid`,`blocked`),
+	 INDEX `pending_uid` (`pending`,`uid`),
+	 INDEX `blocked_uid` (`blocked`,`uid`),
 	 INDEX `uid_rel_network_poll` (`uid`,`rel`,`network`,`poll`(64),`archive`),
 	 INDEX `uid_network_batch` (`uid`,`network`,`batch`(64)),
 	 INDEX `addr_uid` (`addr`(32),`uid`),
 	 INDEX `nurl_uid` (`nurl`(32),`uid`),
-	 INDEX `nick_uid` (`nick`(32),`uid`)
+	 INDEX `nick_uid` (`nick`(32),`uid`),
+	 INDEX `dfrn-id` (`dfrn-id`),
+	 INDEX `issued-id` (`issued-id`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -192,12 +194,12 @@ CREATE TABLE IF NOT EXISTS `contact` (
 CREATE TABLE IF NOT EXISTS `conv` (
 	`id` int(10) unsigned NOT NULL auto_increment,
 	`guid` varchar(64) NOT NULL DEFAULT '',
-	`recips` mediumtext,
+	`recips` text,
 	`uid` int(11) NOT NULL DEFAULT 0,
 	`creator` varchar(255) NOT NULL DEFAULT '',
 	`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	`updated` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
-	`subject` mediumtext,
+	`subject` text,
 	 PRIMARY KEY(`id`),
 	 INDEX `uid` (`uid`)
 ) DEFAULT CHARSET=utf8mb4;
@@ -264,7 +266,8 @@ CREATE TABLE IF NOT EXISTS `fcontact` (
 	`pubkey` text,
 	`updated` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`id`),
-	 INDEX `addr` (`addr`(32))
+	 INDEX `addr` (`addr`(32)),
+	 INDEX `url` (`url`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -349,10 +352,11 @@ CREATE TABLE IF NOT EXISTS `gcontact` (
 	`generation` tinyint(3) NOT NULL DEFAULT 0,
 	`server_url` varchar(255) NOT NULL DEFAULT '',
 	 PRIMARY KEY(`id`),
-	 INDEX `nurl` (`nurl`(32)),
-	 INDEX `name` (`name`(32)),
+	 INDEX `nurl` (`nurl`(64)),
+	 INDEX `name` (`name`(64)),
 	 INDEX `nick` (`nick`(32)),
-	 INDEX `addr` (`addr`(32)),
+	 INDEX `addr` (`addr`(64)),
+	 INDEX `hide_network_updated` (`hide`,`network`,`updated`),
 	 INDEX `updated` (`updated`)
 ) DEFAULT CHARSET=utf8mb4;
 
@@ -368,8 +372,7 @@ CREATE TABLE IF NOT EXISTS `glink` (
 	`updated` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`id`),
 	 UNIQUE INDEX `cid_uid_gcid_zcid` (`cid`,`uid`,`gcid`,`zcid`),
-	 INDEX `gcid` (`gcid`),
-	 INDEX `zcid` (`zcid`)
+	 INDEX `gcid` (`gcid`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -394,8 +397,8 @@ CREATE TABLE IF NOT EXISTS `group_member` (
 	`gid` int(10) unsigned NOT NULL DEFAULT 0,
 	`contact-id` int(10) unsigned NOT NULL DEFAULT 0,
 	 PRIMARY KEY(`id`),
-	 INDEX `cid_contactid` (`cid`,`contact-id`),
-	 INDEX `uid_contactid` (`uid`,`contact-id`),
+	 INDEX `contactid` (`contact-id`),
+	 INDEX `gid_contactid` (`gid`,`contact-id`),
 	 UNIQUE INDEX `uid_gid_contactid` (`uid`,`gid`,`contact-id`)
 ) DEFAULT CHARSET=utf8mb4;
 
@@ -432,7 +435,7 @@ CREATE TABLE IF NOT EXISTS `hook` (
 	`function` varchar(255) NOT NULL DEFAULT '',
 	`priority` int(11) unsigned NOT NULL DEFAULT 0,
 	 PRIMARY KEY(`id`),
-	 INDEX `hook_file_function` (`hook`(30),`file`(60),`function`(30))
+	 UNIQUE INDEX `hook_file_function` (`hook`(50),`file`(80),`function`(60))
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -532,18 +535,13 @@ CREATE TABLE IF NOT EXISTS `item` (
 	 INDEX `uid_created` (`uid`,`created`),
 	 INDEX `uid_unseen_contactid` (`uid`,`unseen`,`contact-id`),
 	 INDEX `uid_network_received` (`uid`,`network`,`received`),
-	 INDEX `uid_received` (`uid`,`received`),
 	 INDEX `uid_network_commented` (`uid`,`network`,`commented`),
-	 INDEX `uid_title` (`uid`,`title`),
 	 INDEX `uid_thrparent` (`uid`,`thr-parent`),
 	 INDEX `uid_parenturi` (`uid`,`parent-uri`),
-	 INDEX `uid_contactid_id` (`uid`,`contact-id`,`id`),
 	 INDEX `uid_contactid_created` (`uid`,`contact-id`,`created`),
 	 INDEX `authorid_created` (`author-id`,`created`),
 	 INDEX `uid_uri` (`uid`,`uri`),
-	 INDEX `uid_wall_created` (`uid`,`wall`,`created`),
 	 INDEX `resource-id` (`resource-id`),
-	 INDEX `uid_type` (`uid`,`type`),
 	 INDEX `contactid_allowcid_allowpid_denycid_denygid` (`contact-id`,`allow_cid`(10),`allow_gid`(10),`deny_cid`(10),`deny_gid`(10)),
 	 INDEX `uid_type_changed` (`uid`,`type`,`changed`),
 	 INDEX `contactid_verb` (`contact-id`,`verb`),
@@ -603,7 +601,6 @@ CREATE TABLE IF NOT EXISTS `mail` (
 	`parent-uri` varchar(255) NOT NULL DEFAULT '',
 	`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`id`),
-	 INDEX `uid` (`uid`),
 	 INDEX `uid_seen` (`uid`,`seen`),
 	 INDEX `convid` (`convid`),
 	 INDEX `uri` (`uri`(64)),
@@ -638,7 +635,7 @@ CREATE TABLE IF NOT EXISTS `manage` (
 	`uid` int(11) NOT NULL DEFAULT 0,
 	`mid` int(11) NOT NULL DEFAULT 0,
 	 PRIMARY KEY(`id`),
-	 INDEX `uid_mid` (`uid`,`mid`)
+	 UNIQUE INDEX `uid_mid` (`uid`,`mid`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -663,11 +660,10 @@ CREATE TABLE IF NOT EXISTS `notify` (
 	`name_cache` tinytext,
 	`msg_cache` mediumtext,
 	 PRIMARY KEY(`id`),
-	 INDEX `uid_hash` (`uid`,`hash`),
-	 INDEX `uid_seen_date` (`uid`,`seen`,`date`),
-	 INDEX `uid_type_link` (`uid`,`type`,`link`),
-	 INDEX `uid_link` (`uid`,`link`),
-	 INDEX `uid_date` (`uid`,`date`)
+	 INDEX `hash_uid` (`hash`,`uid`),
+	 INDEX `seen_uid_date` (`seen`,`uid`,`date`),
+	 INDEX `uid_date` (`uid`,`date`),
+	 INDEX `uid_type_link` (`uid`,`type`,`link`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -679,8 +675,7 @@ CREATE TABLE IF NOT EXISTS `notify-threads` (
 	`master-parent-item` int(10) unsigned NOT NULL DEFAULT 0,
 	`parent-item` int(10) unsigned NOT NULL DEFAULT 0,
 	`receiver-uid` int(11) NOT NULL DEFAULT 0,
-	 PRIMARY KEY(`id`),
-	 INDEX `master-parent-item` (`master-parent-item`)
+	 PRIMARY KEY(`id`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -688,7 +683,7 @@ CREATE TABLE IF NOT EXISTS `notify-threads` (
 --
 CREATE TABLE IF NOT EXISTS `oembed` (
 	`url` varbinary(255) NOT NULL,
-	`content` text,
+	`content` mediumtext,
 	`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`url`),
 	 INDEX `created` (`created`)
@@ -701,7 +696,7 @@ CREATE TABLE IF NOT EXISTS `parsed_url` (
 	`url` varbinary(255) NOT NULL,
 	`guessing` tinyint(1) NOT NULL DEFAULT 0,
 	`oembed` tinyint(1) NOT NULL DEFAULT 0,
-	`content` text,
+	`content` mediumtext,
 	`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	 PRIMARY KEY(`url`,`guessing`,`oembed`),
 	 INDEX `created` (`created`)
@@ -749,7 +744,7 @@ CREATE TABLE IF NOT EXISTS `photo` (
 	 PRIMARY KEY(`id`),
 	 INDEX `uid_contactid` (`uid`,`contact-id`),
 	 INDEX `uid_profile` (`uid`,`profile`),
-	 INDEX `uid_album_created` (`uid`,`album`(32),`created`),
+	 INDEX `uid_album_scale_created` (`uid`,`album`(32),`scale`,`created`),
 	 INDEX `uid_album_resource-id_created` (`uid`,`album`(32),`resource-id`(64),`created`),
 	 INDEX `resource-id` (`resource-id`(64))
 ) DEFAULT CHARSET=utf8mb4;
@@ -760,16 +755,16 @@ CREATE TABLE IF NOT EXISTS `photo` (
 CREATE TABLE IF NOT EXISTS `poll` (
 	`id` int(11) NOT NULL auto_increment,
 	`uid` int(11) NOT NULL DEFAULT 0,
-	`q0` mediumtext,
-	`q1` mediumtext,
-	`q2` mediumtext,
-	`q3` mediumtext,
-	`q4` mediumtext,
-	`q5` mediumtext,
-	`q6` mediumtext,
-	`q7` mediumtext,
-	`q8` mediumtext,
-	`q9` mediumtext,
+	`q0` text,
+	`q1` text,
+	`q2` text,
+	`q3` text,
+	`q4` text,
+	`q5` text,
+	`q6` text,
+	`q7` text,
+	`q8` text,
+	`q9` text,
 	 PRIMARY KEY(`id`),
 	 INDEX `uid` (`uid`)
 ) DEFAULT CHARSET=utf8mb4;
@@ -843,7 +838,8 @@ CREATE TABLE IF NOT EXISTS `profile` (
 	`thumb` varchar(255) NOT NULL DEFAULT '',
 	`publish` tinyint(1) NOT NULL DEFAULT 0,
 	`net-publish` tinyint(1) NOT NULL DEFAULT 0,
-	 PRIMARY KEY(`id`)
+	 PRIMARY KEY(`id`),
+	 INDEX `uid_is-default` (`uid`,`is-default`)
 ) DEFAULT CHARSET=utf8mb4;
 
 --
@@ -979,8 +975,6 @@ CREATE TABLE IF NOT EXISTS `term` (
 	`uid` int(10) unsigned NOT NULL DEFAULT 0,
 	 PRIMARY KEY(`tid`),
 	 INDEX `oid_otype_type_term` (`oid`,`otype`,`type`,`term`),
-	 INDEX `uid_term_tid` (`uid`,`term`(32),`tid`),
-	 INDEX `type_term` (`type`,`term`(32)),
 	 INDEX `uid_otype_type_term_global_created` (`uid`,`otype`,`type`,`term`(32),`global`,`created`),
 	 INDEX `uid_otype_type_url` (`uid`,`otype`,`type`,`url`(64)),
 	 INDEX `guid` (`guid`(64))
@@ -1017,8 +1011,6 @@ CREATE TABLE IF NOT EXISTS `thread` (
 	`mention` tinyint(1) NOT NULL DEFAULT 0,
 	`network` varchar(32) NOT NULL DEFAULT '',
 	 PRIMARY KEY(`iid`),
-	 INDEX `created` (`created`),
-	 INDEX `commented` (`commented`),
 	 INDEX `uid_network_commented` (`uid`,`network`,`commented`),
 	 INDEX `uid_network_created` (`uid`,`network`,`created`),
 	 INDEX `uid_contactid_commented` (`uid`,`contact-id`,`commented`),
@@ -1111,7 +1103,6 @@ CREATE TABLE IF NOT EXISTS `workerqueue` (
 	`created` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
 	`pid` int(11) NOT NULL DEFAULT 0,
 	`executed` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
-	 PRIMARY KEY(`id`),
-	 INDEX `created` (`created`)
+	 PRIMARY KEY(`id`)
 ) DEFAULT CHARSET=utf8mb4;
 
diff --git a/doc/htconfig.md b/doc/htconfig.md
index 54808aaae5..a7dd59d1f5 100644
--- a/doc/htconfig.md
+++ b/doc/htconfig.md
@@ -26,6 +26,13 @@ Example: To set the directory value please add this line to your .htconfig.php:
 * **birthday_input_format** - Default value is "ymd".
 * **block_local_dir** (Boolean) - Blocks the access to the directory of the local users.
 * **curl_range_bytes** - Maximum number of bytes that should be fetched. Default is 0, which mean "no limit".
+* **db_log** - Name of a logfile to log slow database queries
+* **db_loglimit** - If a database call lasts longer than this value it is logged
+* **db_log_index** - Name of a logfile to log queries with bad indexes
+* **db_log_index_watch** - Watchlist of indexes to watch
+* **db_loglimit_index** - Number of index rows needed to be logged for indexes on the watchlist
+* **db_loglimit_index_high** - Number of index rows to be logged anyway (for any index)
+* **db_log_index_blacklist** - Blacklist of indexes that shouldn't be watched
 * **dbclean** (Boolean) - Enable the automatic database cleanup process
 * **default_service_class** -
 * **delivery_batch_count** - Number of deliveries per process. Default value is 1. (Disabled when using the worker)
diff --git a/include/Core/Config.php b/include/Core/Config.php
index 7b7045a9ee..c495bbd4c7 100644
--- a/include/Core/Config.php
+++ b/include/Core/Config.php
@@ -22,6 +22,8 @@ use dbm;
  */
 class Config {
 
+	private static $cache;
+
 	/**
 	 * @brief Loads all configuration values of family into a cached storage.
 	 *
@@ -32,10 +34,17 @@ class Config {
 	 *  The category of the configuration value
 	 * @return void
 	 */
-	public static function load($family) {
+	public static function load($family = "config") {
+
+		// We don't preload "system" anymore.
+		// This reduces the number of database reads a lot.
+		if ($family === 'system') {
+			return;
+		}
+
 		$a = get_app();
 
-		$r = q("SELECT `v`, `k` FROM `config` WHERE `cat` = '%s' ORDER BY `cat`, `k`, `id`", dbesc($family));
+		$r = q("SELECT `v`, `k` FROM `config` WHERE `cat` = '%s'", dbesc($family));
 		if (dbm::is_result($r)) {
 			foreach ($r as $rr) {
 				$k = $rr['k'];
@@ -43,11 +52,9 @@ class Config {
 					$a->config[$k] = $rr['v'];
 				} else {
 					$a->config[$family][$k] = $rr['v'];
+					self::$cache[$family][$k] = $rr['v'];
 				}
 			}
-		} else if ($family != 'config') {
-			// Negative caching
-			$a->config[$family] = "!<unset>!";
 		}
 	}
 
@@ -78,34 +85,38 @@ class Config {
 		$a = get_app();
 
 		if (!$refresh) {
-			// Looking if the whole family isn't set
-			if (isset($a->config[$family])) {
-				if ($a->config[$family] === '!<unset>!') {
-					return $default_value;
-				}
-			}
 
-			if (isset($a->config[$family][$key])) {
-				if ($a->config[$family][$key] === '!<unset>!') {
+			// Do we have the cached value? Then return it
+			if (isset(self::$cache[$family][$key])) {
+				if (self::$cache[$family][$key] === '!<unset>!') {
 					return $default_value;
+				} else {
+					return self::$cache[$family][$key];
 				}
-				return $a->config[$family][$key];
 			}
 		}
 
-		$ret = q("SELECT `v` FROM `config` WHERE `cat` = '%s' AND `k` = '%s' ORDER BY `id` DESC LIMIT 1",
+		$ret = q("SELECT `v` FROM `config` WHERE `cat` = '%s' AND `k` = '%s'",
 			dbesc($family),
 			dbesc($key)
 		);
-		if (count($ret)) {
+		if (dbm::is_result($ret)) {
 			// manage array value
-			$val = (preg_match("|^a:[0-9]+:{.*}$|s", $ret[0]['v'])?unserialize( $ret[0]['v']):$ret[0]['v']);
-			$a->config[$family][$key] = $val;
+			$val = (preg_match("|^a:[0-9]+:{.*}$|s", $ret[0]['v']) ? unserialize($ret[0]['v']) : $ret[0]['v']);
 
+			// Assign the value from the database to the cache
+			self::$cache[$family][$key] = $val;
 			return $val;
-		} else {
-			$a->config[$family][$key] = '!<unset>!';
+		} elseif (isset($a->config[$family][$key])) {
+
+			// Assign the value (mostly) from the .htconfig.php to the cache
+			self::$cache[$family][$key] = $a->config[$family][$key];
+
+			return $a->config[$family][$key];
 		}
+
+		self::$cache[$family][$key] = '!<unset>!';
+
 		return $default_value;
 	}
 
@@ -128,17 +139,28 @@ class Config {
 	public static function set($family, $key, $value) {
 		$a = get_app();
 
+		// We store our setting values in a string variable.
+		// So we have to do the conversion here so that the compare below works.
+		// The exception are array values.
+		$dbvalue = (!is_array($value) ? (string)$value : $value);
+
 		$stored = self::get($family, $key);
 
-		if ($stored == $value) {
+		if ($stored === $dbvalue) {
 			return true;
 		}
 
-		$a->config[$family][$key] = $value;
+		if ($family === 'config') {
+			$a->config[$key] = $dbvalue;
+		} elseif ($family != 'system') {
+			$a->config[$family][$key] = $dbvalue;
+		}
+
+		// Assign the just added value to the cache
+		self::$cache[$family][$key] = $dbvalue;
 
 		// manage array value
-		$dbvalue = (is_array($value) ? serialize($value) : $value);
-		$dbvalue = (is_bool($dbvalue) ? intval($dbvalue) : $dbvalue);
+		$dbvalue = (is_array($value) ? serialize($value) : $dbvalue);
 
 		if (is_null($stored)) {
 			$ret = q("INSERT INTO `config` (`cat`, `k`, `v`) VALUES ('%s', '%s', '%s') ON DUPLICATE KEY UPDATE `v` = '%s'",
@@ -174,9 +196,8 @@ class Config {
 	 */
 	public static function delete($family, $key) {
 
-		$a = get_app();
-		if (x($a->config[$family],$key)) {
-			unset($a->config[$family][$key]);
+		if (isset(self::$cache[$family][$key])) {
+			unset(self::$cache[$family][$key]);
 		}
 		$ret = q("DELETE FROM `config` WHERE `cat` = '%s' AND `k` = '%s'",
 			dbesc($family),
@@ -185,5 +206,4 @@ class Config {
 
 		return $ret;
 	}
-
 }
diff --git a/include/acl_selectors.php b/include/acl_selectors.php
index fccdb80665..f4b644d68f 100644
--- a/include/acl_selectors.php
+++ b/include/acl_selectors.php
@@ -495,6 +495,8 @@ function acl_lookup(App $a, $out_type = 'json') {
 
 	if ($type=='' || $type=='g'){
 
+		/// @todo We should cache this query.
+		// This can be done when we can delete cache entries via wildcard
 		$r = q("SELECT `group`.`id`, `group`.`name`, GROUP_CONCAT(DISTINCT `group_member`.`contact-id` SEPARATOR ',') AS uids
 				FROM `group`
 				INNER JOIN `group_member` ON `group_member`.`gid`=`group`.`id` AND `group_member`.`uid` = `group`.`uid`
diff --git a/include/api.php b/include/api.php
index 64a896b554..ce76103129 100644
--- a/include/api.php
+++ b/include/api.php
@@ -5,6 +5,9 @@
  *
  * @todo Automatically detect if incoming data is HTML or BBCode
  */
+
+use \Friendica\Core\Config;
+
 	require_once('include/HTTPExceptions.php');
 
 	require_once('include/bbcode.php');
@@ -2696,11 +2699,11 @@
 		$logo = App::get_baseurl() . '/images/friendica-64.png';
 		$email = $a->config['admin_email'];
 		$closed = (($a->config['register_policy'] == REGISTER_CLOSED) ? 'true' : 'false');
-		$private = (($a->config['system']['block_public']) ? 'true' : 'false');
+		$private = ((Config::get('system', 'block_public')) ? 'true' : 'false');
 		$textlimit = (string) (($a->config['max_import_size']) ? $a->config['max_import_size'] : 200000);
 		if($a->config['api_import_size'])
 			$texlimit = string($a->config['api_import_size']);
-		$ssl = (($a->config['system']['have_ssl']) ? 'true' : 'false');
+		$ssl = ((Config::get('system', 'have_ssl')) ? 'true' : 'false');
 		$sslserver = (($ssl === 'true') ? str_replace('http:','https:',App::get_baseurl()) : '');
 
 		$config = array(
diff --git a/include/cache.php b/include/cache.php
index e8af8f9de1..98799bcf40 100644
--- a/include/cache.php
+++ b/include/cache.php
@@ -186,7 +186,7 @@ class Cache {
 			set_config("system", "cache_cleared_half_hour", time());
 		}
 
-		if (($max_level <= CACHE_QUARTER_HOUR) AND (get_config("system", "cache_cleared_hour")) < time() - self::duration(CACHE_QUARTER_HOUR)) {
+		if (($max_level <= CACHE_QUARTER_HOUR) AND (get_config("system", "cache_cleared_quarter_hour")) < time() - self::duration(CACHE_QUARTER_HOUR)) {
 			q("DELETE FROM `cache` WHERE `updated` < '%s' AND `expire_mode` = %d",
 				dbesc(datetime_convert('UTC','UTC',"now - 15 minutes")), intval(CACHE_QUARTER_HOUR));
 
diff --git a/include/cli_startup.php b/include/cli_startup.php
index 4cb86adef8..4b66b47a00 100644
--- a/include/cli_startup.php
+++ b/include/cli_startup.php
@@ -1,5 +1,7 @@
 <?php /** @file */
 
+use \Friendica\Core\Config;
+
 require_once('boot.php');
 
 // Everything we need to boot standalone 'background' processes
@@ -8,21 +10,20 @@ function cli_startup() {
 
 	global $a, $db;
 
-	if(is_null($a)) {
+	if (is_null($a)) {
 		$a = new App;
 	}
 
-	if(is_null($db)) {
-	    @include(".htconfig.php");
-    	require_once("dba.php");
-	    $db = new dba($db_host, $db_user, $db_pass, $db_data);
-    	unset($db_host, $db_user, $db_pass, $db_data);
+	if (is_null($db)) {
+		@include(".htconfig.php");
+		require_once("dba.php");
+		$db = new dba($db_host, $db_user, $db_pass, $db_data);
+		unset($db_host, $db_user, $db_pass, $db_data);
   	};
 
 	require_once('include/session.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/include/contact_widgets.php b/include/contact_widgets.php
index fee569e94d..1e35db2c78 100644
--- a/include/contact_widgets.php
+++ b/include/contact_widgets.php
@@ -90,7 +90,7 @@ function networks_widget($baseurl,$selected = '') {
 
 	$extra_sql = unavailable_networks();
 
-	$r = q("SELECT DISTINCT(`network`) FROM `contact` WHERE `uid` = %d AND NOT `self` $extra_sql ORDER BY `network`",
+	$r = q("SELECT DISTINCT(`network`) FROM `contact` WHERE `uid` = %d AND `network` != '' $extra_sql ORDER BY `network`",
 		intval(local_user())
 	);
 
diff --git a/include/create_shadowentry.php b/include/create_shadowentry.php
index f06a0dd1bf..005295c978 100644
--- a/include/create_shadowentry.php
+++ b/include/create_shadowentry.php
@@ -5,6 +5,9 @@
  *
  * This script is started from mod/item.php to save some time when doing a post.
  */
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/threads.php");
 
@@ -21,8 +24,7 @@ function create_shadowentry_run($argv, $argc) {
 		unset($db_host, $db_user, $db_pass, $db_data);
 	}
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	if ($argc != 2) {
 		return;
diff --git a/include/cron.php b/include/cron.php
index 059bcea437..2fc8de51c5 100644
--- a/include/cron.php
+++ b/include/cron.php
@@ -10,6 +10,8 @@ if (!file_exists("boot.php") AND (sizeof($_SERVER["argv"]) != 0)) {
 	chdir($directory);
 }
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/photos.php");
 require_once("include/user.php");
@@ -38,8 +40,7 @@ function cron_run(&$argv, &$argc){
 	require_once('mod/nodeinfo.php');
 	require_once('include/post_update.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	// Don't check this stuff if the function is called by the poller
 	if (App::callstack() != "poller_run") {
@@ -239,11 +240,13 @@ function cron_poll_contacts($argc, $argv) {
 		: ''
 	);
 
-	$contacts = q("SELECT `contact`.`id` FROM `contact` INNER JOIN `user` ON `user`.`uid` = `contact`.`uid`
-		WHERE `rel` IN (%d, %d) AND `poll` != '' AND `network` IN ('%s', '%s', '%s', '%s', '%s', '%s')
-		$sql_extra
-		AND NOT `self` AND NOT `contact`.`blocked` AND NOT `contact`.`readonly` AND NOT `contact`.`archive`
-		AND NOT `user`.`account_expired` AND NOT `user`.`account_removed` $abandon_sql ORDER BY RAND()",
+	$contacts = q("SELECT `contact`.`id` FROM `user`
+			STRAIGHT_JOIN `contact`
+			ON `contact`.`uid` = `user`.`uid` AND `contact`.`rel` IN (%d, %d) AND `contact`.`poll` != ''
+				AND `contact`.`network` IN ('%s', '%s', '%s', '%s', '%s', '%s') $sql_extra
+				AND NOT `contact`.`self` AND NOT `contact`.`blocked` AND NOT `contact`.`readonly`
+				AND NOT `contact`.`archive`
+			WHERE NOT `user`.`account_expired` AND NOT `user`.`account_removed` $abandon_sql ORDER BY RAND()",
 		intval(CONTACT_IS_SHARING),
 		intval(CONTACT_IS_FRIEND),
 		dbesc(NETWORK_DFRN),
diff --git a/include/cronhooks.php b/include/cronhooks.php
index 7524a0c3a8..72b86be427 100644
--- a/include/cronhooks.php
+++ b/include/cronhooks.php
@@ -1,7 +1,8 @@
 <?php
 
-require_once("boot.php");
+use \Friendica\Core\Config;
 
+require_once("boot.php");
 
 function cronhooks_run(&$argv, &$argc){
 	global $a, $db;
@@ -20,8 +21,7 @@ function cronhooks_run(&$argv, &$argc){
 	require_once('include/session.php');
 	require_once('include/datetime.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	// Don't check this stuff if the function is called by the poller
 	if (App::callstack() != "poller_run") {
diff --git a/include/cronjobs.php b/include/cronjobs.php
index 1511efbe0d..f0a56370b8 100644
--- a/include/cronjobs.php
+++ b/include/cronjobs.php
@@ -1,4 +1,6 @@
 <?php
+use \Friendica\Core\Config;
+
 if (!file_exists("boot.php") AND (sizeof($_SERVER["argv"]) != 0)) {
 	$directory = dirname($_SERVER["argv"][0]);
 
@@ -33,8 +35,7 @@ function cronjobs_run(&$argv, &$argc){
 	require_once('include/post_update.php');
 	require_once('mod/nodeinfo.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/include/datetime.php b/include/datetime.php
index a17c405dc3..779c7a5aad 100644
--- a/include/datetime.php
+++ b/include/datetime.php
@@ -4,6 +4,7 @@
  * @brief Some functions for date and time related tasks.
  */
 
+use \Friendica\Core\Config;
 
 /**
  * @brief Two-level sort for timezones.
@@ -271,8 +272,9 @@ function datetimesel($format, $min, $max, $default, $label, $id = 'datetimepicke
 	$lang = substr(get_browser_language(), 0, 2);
 
 	// Check if the detected language is supported by the picker
-	if (!in_array($lang, array("ar", "ro", "id", "bg", "fa", "ru", "uk", "en", "el", "de", "nl", "tr", "fr", "es", "th", "pl", "pt", "ch", "se", "kr", "it", "da", "no", "ja", "vi", "sl", "cs", "hu")))
-		$lang = ((isset($a->config['system']['language'])) ? $a->config['system']['language'] : 'en');
+	if (!in_array($lang, array("ar", "ro", "id", "bg", "fa", "ru", "uk", "en", "el", "de", "nl", "tr", "fr", "es", "th", "pl", "pt", "ch", "se", "kr", "it", "da", "no", "ja", "vi", "sl", "cs", "hu"))) {
+		$lang = Config::get('system', 'language', 'en');
+	}
 
 	$o = '';
 	$dateformat = '';
diff --git a/include/dba.php b/include/dba.php
index 920027cbcf..8e2d18db60 100644
--- a/include/dba.php
+++ b/include/dba.php
@@ -138,6 +138,62 @@ class dba {
 		return $return;
 	}
 
+	/**
+	 * @brief Analyze a database query and log this if some conditions are met.
+	 *
+	 * @param string $query The database query that will be analyzed
+	 */
+	public function log_index($query) {
+		$a = get_app();
+
+		if ($a->config["system"]["db_log_index"] == "") {
+			return;
+		}
+
+		// Don't explain an explain statement
+		if (strtolower(substr($query, 0, 7)) == "explain") {
+			return;
+		}
+
+		// Only do the explain on "select", "update" and "delete"
+		if (!in_array(strtolower(substr($query, 0, 6)), array("select", "update", "delete"))) {
+			return;
+		}
+
+		$r = $this->q("EXPLAIN ".$query);
+		if (!dbm::is_result($r)) {
+			return;
+		}
+
+		$watchlist = explode(',', $a->config["system"]["db_log_index_watch"]);
+		$blacklist = explode(',', $a->config["system"]["db_log_index_blacklist"]);
+
+		foreach ($r AS $row) {
+			if ((intval($a->config["system"]["db_loglimit_index"]) > 0)) {
+				$log = (in_array($row['key'], $watchlist) AND
+					($row['rows'] >= intval($a->config["system"]["db_loglimit_index"])));
+			} else
+				$log = false;
+
+			if ((intval($a->config["system"]["db_loglimit_index_high"]) > 0) AND ($row['rows'] >= intval($a->config["system"]["db_loglimit_index_high"]))) {
+				$log = true;
+			}
+
+			if (in_array($row['key'], $blacklist) OR ($row['key'] == "")) {
+				$log = false;
+			}
+
+			if ($log) {
+				$backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+				@file_put_contents($a->config["system"]["db_log_index"], datetime_convert()."\t".
+						$row['key']."\t".$row['rows']."\t".$row['Extra']."\t".
+						basename($backtrace[1]["file"])."\t".
+						$backtrace[1]["line"]."\t".$backtrace[2]["function"]."\t".
+						substr($query, 0, 2000)."\n", FILE_APPEND);
+			}
+		}
+	}
+
 	public function q($sql, $onlyquery = false) {
 		$a = get_app();
 
@@ -375,6 +431,9 @@ function q($sql) {
 		//logger("dba: q: $stmt", LOGGER_ALL);
 		if ($stmt === false)
 			logger('dba: vsprintf error: ' . print_r(debug_backtrace(),true), LOGGER_DEBUG);
+
+		$db->log_index($stmt);
+
 		return $db->q($stmt);
 	}
 
@@ -408,6 +467,9 @@ function qu($sql) {
 		$stmt = @vsprintf($sql,$args); // Disabled warnings
 		if ($stmt === false)
 			logger('dba: vsprintf error: ' . print_r(debug_backtrace(),true), LOGGER_DEBUG);
+
+		$db->log_index($stmt);
+
 		$db->q("SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;");
 		$retval = $db->q($stmt);
 		$db->q("SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;");
diff --git a/include/dbclean.php b/include/dbclean.php
index c80e5a3be3..8408ad1882 100644
--- a/include/dbclean.php
+++ b/include/dbclean.php
@@ -23,8 +23,7 @@ function dbclean_run(&$argv, &$argc) {
 		unset($db_host, $db_user, $db_pass, $db_data);
 	}
 
-	Config::load('config');
-	Config::load('system');
+	Config::load();
 
 	if (!Config::get('system', 'dbclean', false)) {
 		return;
diff --git a/include/dbstructure.php b/include/dbstructure.php
index 5c89f49fb9..346920ab07 100644
--- a/include/dbstructure.php
+++ b/include/dbstructure.php
@@ -176,15 +176,6 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 		$definition = db_definition($charset);
 	}
 
-	// Ensure index conversion to unique removes duplicates
-	$sql_config = "SET session old_alter_table=1;";
-	if ($verbose) {
-		echo $sql_config."\n";
-	}
-	if ($action) {
-		$db->q($sql_config);
-	}
-
 	// MySQL >= 5.7.4 doesn't support the IGNORE keyword in ALTER TABLE statements
 	if ((version_compare($db->server_info(), '5.7.4') >= 0) AND
 		!(strpos($db->server_info(), 'MariaDB') !== false)) {
@@ -204,6 +195,27 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 			}
 			$is_new_table = True;
 		} else {
+			$is_unique = false;
+			$temp_name = $name;
+
+			foreach ($structure["indexes"] AS $indexname => $fieldnames) {
+				if (isset($database[$name]["indexes"][$indexname])) {
+					$current_index_definition = implode(",",$database[$name]["indexes"][$indexname]);
+				} else {
+					$current_index_definition = "__NOT_SET__";
+				}
+				$new_index_definition = implode(",",$fieldnames);
+				if ($current_index_definition != $new_index_definition) {
+					if ($fieldnames[0] == "UNIQUE") {
+						$is_unique = true;
+						// Deactivated. See below for the reason
+						//if ($ignore == "") {
+						//	$temp_name = "temp-".$name;
+						//}
+					}
+				}
+			}
+
 			/*
 			 * Drop the index if it isn't present in the definition
 			 * or the definition differ from current status
@@ -219,7 +231,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 				if ($current_index_definition != $new_index_definition && substr($indexname, 0, 6) != 'local_') {
 					$sql2=db_drop_index($indexname);
 					if ($sql3 == "") {
-						$sql3 = "ALTER".$ignore." TABLE `".$name."` ".$sql2;
+						$sql3 = "ALTER".$ignore." TABLE `".$temp_name."` ".$sql2;
 					} else {
 						$sql3 .= ", ".$sql2;
 					}
@@ -230,7 +242,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 				if (!isset($database[$name]["fields"][$fieldname])) {
 					$sql2=db_add_table_field($fieldname, $parameters);
 					if ($sql3 == "") {
-						$sql3 = "ALTER TABLE `".$name."` ".$sql2;
+						$sql3 = "ALTER TABLE `".$temp_name."` ".$sql2;
 					} else {
 						$sql3 .= ", ".$sql2;
 					}
@@ -241,7 +253,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 					if ($current_field_definition != $new_field_definition) {
 						$sql2=db_modify_table_field($fieldname, $parameters);
 						if ($sql3 == "") {
-							$sql3 = "ALTER TABLE `".$name."` ".$sql2;
+							$sql3 = "ALTER TABLE `".$temp_name."` ".$sql2;
 						} else {
 							$sql3 .= ", ".$sql2;
 						}
@@ -268,7 +280,7 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 					$sql2=db_create_index($indexname, $fieldnames);
 					if ($sql2 != "") {
 						if ($sql3 == "")
-							$sql3 = "ALTER" . $ignore . " TABLE `".$name."` ".$sql2;
+							$sql3 = "ALTER" . $ignore . " TABLE `".$temp_name."` ".$sql2;
 						else
 							$sql3 .= ", ".$sql2;
 					}
@@ -278,13 +290,77 @@ function update_structure($verbose, $action, $tables=null, $definition=null) {
 		if ($sql3 != "") {
 			$sql3 .= ";";
 
-			if ($verbose)
+			if ($verbose) {
+				// Ensure index conversion to unique removes duplicates
+				if ($is_unique) {
+					// By now the alternative is commented out.
+					// This is a preparation for the time when we found a good SQL routine.
+					//if ($ignore != "") {
+						echo "SET session old_alter_table=1;\n";
+					//} else {
+					//	echo "CREATE TABLE `".$temp_name."` LIKE `".$name."`;\n";
+					//}
+				}
+
 				echo $sql3."\n";
 
+				if ($is_unique) {
+					// By now the alternative is commented out.
+					// This is a preparation for the time when we found a good SQL routine.
+					//if ($ignore != "") {
+						echo "SET session old_alter_table=0;\n";
+					//} else {
+					//	echo "INSERT IGNORE INTO `".$temp_name."` SELECT * FROM `".$name."`;\n";
+					//	echo "DROP TABLE `".$name."`;\n";
+					//	echo "RENAME TABLE `".$temp_name."` TO `".$name."`;\n";
+					//}
+				}
+			}
+
 			if ($action) {
+				// Ensure index conversion to unique removes duplicates
+				if ($is_unique) {
+					// By now the alternative is commented out.
+					// This is a preparation for the time when we found a good SQL routine.
+					//if ($ignore != "") {
+						$db->q("SET session old_alter_table=1;");
+					//} else {
+					//	$r = $db->q("CREATE TABLE `".$temp_name."` LIKE `".$name."`;");
+					//	if (!dbm::is_result($r)) {
+					//		$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+					//		return $errors;
+					//	}
+					//}
+				}
+
 				$r = @$db->q($sql3);
-				if (dbm::is_result($r))
+				if (!dbm::is_result($r))
 					$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+
+				if ($is_unique) {
+					// By now the alternative is commented out.
+					// This is a preparation for the time when we found a good SQL routine.
+					//if ($ignore != "") {
+						$db->q("SET session old_alter_table=0;");
+					//} else {
+					//	We have to check if "INSERT IGNORE" will work on newer MySQL versions
+					//	$r = $db->q("INSERT IGNORE INTO `".$temp_name."` SELECT * FROM `".$name."`;");
+					//	if (!dbm::is_result($r)) {
+					//		$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+					//		return $errors;
+					//	}
+					//	$r = $db->q("DROP TABLE `".$name."`;");
+					//	if (!dbm::is_result($r)) {
+					//		$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+					//		return $errors;
+					//	}
+					//	$r = $db->q("RENAME TABLE `".$temp_name."` TO `".$name."`;");
+					//	if (!dbm::is_result($r)) {
+					//		$errors .= t('Errors encountered performing database changes.').$sql3.EOL;
+					//		return $errors;
+					//	}
+					//}
+				}
 			}
 		}
 	}
@@ -419,7 +495,7 @@ function db_definition($charset) {
 	$database["addon"] = array(
 			"fields" => array(
 					"id" => array("type" => "int(11)", "not null" => "1", "extra" => "auto_increment", "primary" => "1"),
-					"name" => array("type" => "varchar(255)", "not null" => "1", "default" => ""),
+					"name" => array("type" => "varchar(190)", "not null" => "1", "default" => ""),
 					"version" => array("type" => "varchar(255)", "not null" => "1", "default" => ""),
 					"installed" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0"),
 					"hidden" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0"),
@@ -428,6 +504,7 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
+					"name" => array("UNIQUE", "name"),
 					)
 			);
 	$database["attach"] = array(
@@ -465,13 +542,12 @@ function db_definition($charset) {
 	$database["cache"] = array(
 			"fields" => array(
 					"k" => array("type" => "varbinary(255)", "not null" => "1", "primary" => "1"),
-					"v" => array("type" => "text"),
+					"v" => array("type" => "mediumtext"),
 					"expire_mode" => array("type" => "int(11)", "not null" => "1", "default" => "0"),
 					"updated" => array("type" => "datetime", "not null" => "1", "default" => "0000-00-00 00:00:00"),
 					),
 			"indexes" => array(
 					"PRIMARY" => array("k"),
-					"updated" => array("updated"),
 					"expire_mode_updated" => array("expire_mode", "updated"),
 					)
 			);
@@ -506,7 +582,7 @@ function db_definition($charset) {
 					"id" => array("type" => "int(10) unsigned", "not null" => "1", "extra" => "auto_increment", "primary" => "1"),
 					"cat" => array("type" => "varbinary(255)", "not null" => "1", "default" => ""),
 					"k" => array("type" => "varbinary(255)", "not null" => "1", "default" => ""),
-					"v" => array("type" => "text"),
+					"v" => array("type" => "mediumtext"),
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
@@ -582,32 +658,34 @@ function db_definition($charset) {
 					"bd" => array("type" => "date", "not null" => "1", "default" => "0000-00-00"),
 					"notify_new_posts" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0"),
 					"fetch_further_information" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0"),
-					"ffi_keyword_blacklist" => array("type" => "mediumtext"),
+					"ffi_keyword_blacklist" => array("type" => "text"),
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
 					"uid_name" => array("uid", "name"),
-					"uid_self" => array("uid", "self"),
+					"self_uid" => array("self", "uid"),
 					"alias_uid" => array("alias(32)", "uid"),
-					"uid_pending" => array("uid", "pending"),
-					"uid_blocked" => array("uid", "blocked"),
+					"pending_uid" => array("pending", "uid"),
+					"blocked_uid" => array("blocked", "uid"),
 					"uid_rel_network_poll" => array("uid", "rel", "network", "poll(64)", "archive"),
 					"uid_network_batch" => array("uid", "network", "batch(64)"),
 					"addr_uid" => array("addr(32)", "uid"),
 					"nurl_uid" => array("nurl(32)", "uid"),
 					"nick_uid" => array("nick(32)", "uid"),
+					"dfrn-id" => array("dfrn-id"),
+					"issued-id" => array("issued-id"),
 					)
 			);
 	$database["conv"] = array(
 			"fields" => array(
 					"id" => array("type" => "int(10) unsigned", "not null" => "1", "extra" => "auto_increment", "primary" => "1"),
 					"guid" => array("type" => "varchar(64)", "not null" => "1", "default" => ""),
-					"recips" => array("type" => "mediumtext"),
+					"recips" => array("type" => "text"),
 					"uid" => array("type" => "int(11)", "not null" => "1", "default" => "0"),
 					"creator" => array("type" => "varchar(255)", "not null" => "1", "default" => ""),
 					"created" => array("type" => "datetime", "not null" => "1", "default" => "0000-00-00 00:00:00"),
 					"updated" => array("type" => "datetime", "not null" => "1", "default" => "0000-00-00 00:00:00"),
-					"subject" => array("type" => "mediumtext"),
+					"subject" => array("type" => "text"),
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
@@ -677,6 +755,7 @@ function db_definition($charset) {
 			"indexes" => array(
 					"PRIMARY" => array("id"),
 					"addr" => array("addr(32)"),
+					"url" => array("url"),
 					)
 			);
 	$database["ffinder"] = array(
@@ -761,10 +840,11 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"nurl" => array("nurl(32)"),
-					"name" => array("name(32)"),
+					"nurl" => array("nurl(64)"),
+					"name" => array("name(64)"),
 					"nick" => array("nick(32)"),
-					"addr" => array("addr(32)"),
+					"addr" => array("addr(64)"),
+					"hide_network_updated" => array("hide", "network", "updated"),
 					"updated" => array("updated"),
 					)
 			);
@@ -781,7 +861,6 @@ function db_definition($charset) {
 					"PRIMARY" => array("id"),
 					"cid_uid_gcid_zcid" => array("UNIQUE", "cid","uid","gcid","zcid"),
 					"gcid" => array("gcid"),
-					"zcid" => array("zcid"),
 					)
 			);
 	$database["group"] = array(
@@ -806,8 +885,8 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
+					"contactid" => array("contact-id"),
 					"gid_contactid" => array("gid", "contact-id"),
-					"uid_contactid" => array("uid", "contact-id"),
 					"uid_gid_contactid" => array("UNIQUE", "uid", "gid", "contact-id"),
 					)
 			);
@@ -844,7 +923,7 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"hook_file_function" => array("hook(30)","file(60)","function(30)"),
+					"hook_file_function" => array("UNIQUE", "hook(50)","file(80)","function(60)"),
 					)
 			);
 	$database["intro"] = array(
@@ -944,19 +1023,14 @@ function db_definition($charset) {
 					"uid_created" => array("uid","created"),
 					"uid_unseen_contactid" => array("uid","unseen","contact-id"),
 					"uid_network_received" => array("uid","network","received"),
-					"uid_received" => array("uid","received"),
 					"uid_network_commented" => array("uid","network","commented"),
-					"uid_title" => array("uid","title"),
 					"uid_thrparent" => array("uid","thr-parent"),
 					"uid_parenturi" => array("uid","parent-uri"),
-					"uid_contactid_id" => array("uid","contact-id","id"),
 					"uid_contactid_created" => array("uid","contact-id","created"),
 					"authorid_created" => array("author-id","created"),
 					"uid_uri" => array("uid", "uri"),
-					"uid_wall_created" => array("uid","wall","created"),
 					"resource-id" => array("resource-id"),
-					"uid_type" => array("uid","type"),
-					"contactid_allowcid_allowpid_denycid_denygid" => array("contact-id","allow_cid(10)","allow_gid(10)","deny_cid(10)","deny_gid(10)"),
+					"contactid_allowcid_allowpid_denycid_denygid" => array("contact-id","allow_cid(10)","allow_gid(10)","deny_cid(10)","deny_gid(10)"), //
 					"uid_type_changed" => array("uid","type","changed"),
 					"contactid_verb" => array("contact-id","verb"),
 					"deleted_changed" => array("deleted","changed"),
@@ -1015,7 +1089,6 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"uid" => array("uid"),
 					"uid_seen" => array("uid", "seen"),
 					"convid" => array("convid"),
 					"uri" => array("uri(64)"),
@@ -1050,7 +1123,7 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"uid_mid" => array("uid","mid"),
+					"uid_mid" => array("UNIQUE", "uid","mid"),
 					)
 			);
 	$database["notify"] = array(
@@ -1075,11 +1148,10 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"uid_hash" => array("uid", "hash"),
-					"uid_seen_date" => array("uid", "seen", "date"),
-					"uid_type_link" => array("uid", "type", "link"),
-					"uid_link" => array("uid", "link"),
+					"hash_uid" => array("hash", "uid"),
+					"seen_uid_date" => array("seen", "uid", "date"),
 					"uid_date" => array("uid", "date"),
+					"uid_type_link" => array("uid", "type", "link"),
 					)
 			);
 	$database["notify-threads"] = array(
@@ -1092,13 +1164,12 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"master-parent-item" => array("master-parent-item"),
 					)
 			);
 	$database["oembed"] = array(
 			"fields" => array(
 					"url" => array("type" => "varbinary(255)", "not null" => "1", "primary" => "1"),
-					"content" => array("type" => "text"),
+					"content" => array("type" => "mediumtext"),
 					"created" => array("type" => "datetime", "not null" => "1", "default" => "0000-00-00 00:00:00"),
 					),
 			"indexes" => array(
@@ -1111,7 +1182,7 @@ function db_definition($charset) {
 					"url" => array("type" => "varbinary(255)", "not null" => "1", "primary" => "1"),
 					"guessing" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0", "primary" => "1"),
 					"oembed" => array("type" => "tinyint(1)", "not null" => "1", "default" => "0", "primary" => "1"),
-					"content" => array("type" => "text"),
+					"content" => array("type" => "mediumtext"),
 					"created" => array("type" => "datetime", "not null" => "1", "default" => "0000-00-00 00:00:00"),
 					),
 			"indexes" => array(
@@ -1161,7 +1232,7 @@ function db_definition($charset) {
 					"PRIMARY" => array("id"),
 					"uid_contactid" => array("uid", "contact-id"),
 					"uid_profile" => array("uid", "profile"),
-					"uid_album_created" => array("uid", "album(32)", "created"),
+					"uid_album_scale_created" => array("uid", "album(32)", "scale", "created"),
 					"uid_album_resource-id_created" => array("uid", "album(32)", "resource-id(64)", "created"),
 					"resource-id" => array("resource-id(64)"),
 					)
@@ -1170,16 +1241,16 @@ function db_definition($charset) {
 			"fields" => array(
 					"id" => array("type" => "int(11)", "not null" => "1", "extra" => "auto_increment", "primary" => "1"),
 					"uid" => array("type" => "int(11)", "not null" => "1", "default" => "0"),
-					"q0" => array("type" => "mediumtext"),
-					"q1" => array("type" => "mediumtext"),
-					"q2" => array("type" => "mediumtext"),
-					"q3" => array("type" => "mediumtext"),
-					"q4" => array("type" => "mediumtext"),
-					"q5" => array("type" => "mediumtext"),
-					"q6" => array("type" => "mediumtext"),
-					"q7" => array("type" => "mediumtext"),
-					"q8" => array("type" => "mediumtext"),
-					"q9" => array("type" => "mediumtext"),
+					"q0" => array("type" => "text"),
+					"q1" => array("type" => "text"),
+					"q2" => array("type" => "text"),
+					"q3" => array("type" => "text"),
+					"q4" => array("type" => "text"),
+					"q5" => array("type" => "text"),
+					"q6" => array("type" => "text"),
+					"q7" => array("type" => "text"),
+					"q8" => array("type" => "text"),
+					"q9" => array("type" => "text"),
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
@@ -1256,6 +1327,7 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
+					"uid_is-default" => array("uid", "is-default"),
 					)
 			);
 	$database["profile_check"] = array(
@@ -1391,8 +1463,6 @@ function db_definition($charset) {
 			"indexes" => array(
 					"PRIMARY" => array("tid"),
 					"oid_otype_type_term" => array("oid","otype","type","term"),
-					"uid_term_tid" => array("uid","term(32)","tid"),
-					"type_term" => array("type","term(32)"),
 					"uid_otype_type_term_global_created" => array("uid","otype","type","term(32)","global","created"),
 					"uid_otype_type_url" => array("uid","otype","type","url(64)"),
 					"guid" => array("guid(64)"),
@@ -1429,8 +1499,6 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("iid"),
-					"created" => array("created"),
-					"commented" => array("commented"),
 					"uid_network_commented" => array("uid","network","commented"),
 					"uid_network_created" => array("uid","network","created"),
 					"uid_contactid_commented" => array("uid","contact-id","commented"),
@@ -1524,7 +1592,6 @@ function db_definition($charset) {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
-					"created" => array("created"),
 					)
 			);
 
diff --git a/include/dbupdate.php b/include/dbupdate.php
index 28f1de340b..3583be3106 100644
--- a/include/dbupdate.php
+++ b/include/dbupdate.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 
 function dbupdate_run(&$argv, &$argc) {
@@ -16,8 +18,7 @@ function dbupdate_run(&$argv, &$argc) {
 		        unset($db_host, $db_user, $db_pass, $db_data);
 	}
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	update_db($a);
 }
diff --git a/include/delivery.php b/include/delivery.php
index dd7535592f..5000a1edb9 100644
--- a/include/delivery.php
+++ b/include/delivery.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once('include/queue_fn.php');
 require_once('include/html2plain.php');
@@ -27,8 +30,7 @@ function delivery_run(&$argv, &$argc){
 	require_once('include/bbcode.php');
 	require_once('include/email.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	load_hooks();
 
diff --git a/include/dfrn.php b/include/dfrn.php
index 5e4f037796..ccb43fa98e 100644
--- a/include/dfrn.php
+++ b/include/dfrn.php
@@ -194,7 +194,7 @@ class dfrn {
 			`contact`.`name-date`, `contact`.`uri-date`, `contact`.`avatar-date`,
 			`contact`.`thumb`, `contact`.`dfrn-id`, `contact`.`self`,
 			`sign`.`signed_text`, `sign`.`signature`, `sign`.`signer`
-			FROM `item` USE INDEX (`uid_wall_changed`, `uid_type_changed`) $sql_post_table
+			FROM `item` USE INDEX (`uid_wall_changed`) $sql_post_table
 			STRAIGHT_JOIN `contact` ON `contact`.`id` = `item`.`contact-id`
 			AND (NOT `contact`.`blocked` OR `contact`.`pending`)
 			LEFT JOIN `sign` ON `sign`.`iid` = `item`.`id`
diff --git a/include/diaspora.php b/include/diaspora.php
index fc88c79bf2..fdbc0479f9 100644
--- a/include/diaspora.php
+++ b/include/diaspora.php
@@ -45,13 +45,13 @@ class Diaspora {
 
 		foreach($servers AS $server) {
 			$server = trim($server);
+			$addr = "relay@".str_replace("http://", "", normalise_link($server));
 			$batch = $server."/receive/public";
 
-			$relais = q("SELECT `batch`, `id`, `name`,`network` FROM `contact` WHERE `uid` = 0 AND `batch` = '%s' LIMIT 1", dbesc($batch));
+			$relais = q("SELECT `batch`, `id`, `name`,`network` FROM `contact` WHERE `uid` = 0 AND `batch` = '%s' AND `addr` = '%s' AND `nurl` = '%s' LIMIT 1",
+					dbesc($batch), dbesc($addr), dbesc(normalise_link($server)));
 
 			if (!$relais) {
-				$addr = "relay@".str_replace("http://", "", normalise_link($server));
-
 				$r = q("INSERT INTO `contact` (`uid`, `created`, `name`, `nick`, `addr`, `url`, `nurl`, `batch`, `network`, `rel`, `blocked`, `pending`, `writable`, `name-date`, `uri-date`, `avatar-date`)
 					VALUES (0, '%s', '%s', 'relay', '%s', '%s', '%s', '%s', '%s', %d, 0, 0, 1, '%s', '%s', '%s')",
 					datetime_convert(),
diff --git a/include/directory.php b/include/directory.php
index 85476bd5fd..2ca367d369 100644
--- a/include/directory.php
+++ b/include/directory.php
@@ -1,6 +1,8 @@
 <?php
 require_once("boot.php");
 
+use \Friendica\Core\Config;
+
 function directory_run(&$argv, &$argc){
 	global $a, $db;
 
@@ -15,15 +17,11 @@ function directory_run(&$argv, &$argc){
 				unset($db_host, $db_user, $db_pass, $db_data);
 	};
 
-	load_config('config');
-	load_config('system');
-
+	Config::load();
 
 	if($argc != 2)
 		return;
 
-	load_config('system');
-
 	load_hooks();
 
 
diff --git a/include/discover_poco.php b/include/discover_poco.php
index bf3e47edd9..8146368784 100644
--- a/include/discover_poco.php
+++ b/include/discover_poco.php
@@ -1,9 +1,10 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/socgraph.php");
 
-
 function discover_poco_run(&$argv, &$argc){
 	global $a, $db;
 
@@ -21,8 +22,7 @@ function discover_poco_run(&$argv, &$argc){
 	require_once('include/session.php');
 	require_once('include/datetime.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	// Don't check this stuff if the function is called by the poller
 	if (App::callstack() != "poller_run")
diff --git a/include/expire.php b/include/expire.php
index e3313a78be..855d7fb5e4 100644
--- a/include/expire.php
+++ b/include/expire.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 
 function expire_run(&$argv, &$argc){
@@ -10,19 +12,18 @@ function expire_run(&$argv, &$argc){
 	}
 
 	if(is_null($db)) {
-	    @include(".htconfig.php");
-    	require_once("include/dba.php");
-	    $db = new dba($db_host, $db_user, $db_pass, $db_data);
-    	unset($db_host, $db_user, $db_pass, $db_data);
-  	};
+		@include(".htconfig.php");
+		require_once("include/dba.php");
+		$db = new dba($db_host, $db_user, $db_pass, $db_data);
+		unset($db_host, $db_user, $db_pass, $db_data);
+	};
 
 	require_once('include/session.php');
 	require_once('include/datetime.php');
 	require_once('include/items.php');
 	require_once('include/Contact.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/include/gprobe.php b/include/gprobe.php
index 7169aada3f..4407fa6d6c 100644
--- a/include/gprobe.php
+++ b/include/gprobe.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once('include/Scrape.php');
 require_once('include/socgraph.php');
@@ -21,8 +23,7 @@ function gprobe_run(&$argv, &$argc){
 	require_once('include/session.php');
 	require_once('include/datetime.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/include/identity.php b/include/identity.php
index c18bc3a805..d3852b2c2c 100644
--- a/include/identity.php
+++ b/include/identity.php
@@ -6,6 +6,7 @@
 require_once('include/ForumManager.php');
 require_once('include/bbcode.php');
 require_once("mod/proxy.php");
+require_once('include/cache.php');
 
 /**
  *
@@ -453,15 +454,21 @@ function get_birthdays() {
 	$bd_format = t('g A l F d') ; // 8 AM Friday January 18
 	$bd_short = t('F d');
 
-	$r = q("SELECT `event`.*, `event`.`id` AS `eid`, `contact`.* FROM `event`
-			INNER JOIN `contact` ON `contact`.`id` = `event`.`cid`
-			WHERE `event`.`uid` = %d AND `type` = 'birthday' AND `start` < '%s' AND `finish` > '%s'
-			ORDER BY `start` ASC ",
-			intval(local_user()),
-			dbesc(datetime_convert('UTC','UTC','now + 6 days')),
-			dbesc(datetime_convert('UTC','UTC','now'))
-	);
-
+	$cachekey = "get_birthdays:".local_user();
+	$r = Cache::get($cachekey);
+	if (is_null($r)) {
+		$r = q("SELECT `event`.*, `event`.`id` AS `eid`, `contact`.* FROM `event`
+				INNER JOIN `contact` ON `contact`.`id` = `event`.`cid`
+				WHERE `event`.`uid` = %d AND `type` = 'birthday' AND `start` < '%s' AND `finish` > '%s'
+				ORDER BY `start` ASC ",
+				intval(local_user()),
+				dbesc(datetime_convert('UTC','UTC','now + 6 days')),
+				dbesc(datetime_convert('UTC','UTC','now'))
+		);
+		if (dbm::is_result($r)) {
+			Cache::set($cachekey, $r, CACHE_HOUR);
+		}
+	}
 	if (dbm::is_result($r)) {
 		$total = 0;
 		$now = strtotime('now');
diff --git a/include/notifier.php b/include/notifier.php
index 7bea239c6f..24830a11ab 100644
--- a/include/notifier.php
+++ b/include/notifier.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once('include/queue_fn.php');
 require_once('include/html2plain.php');
@@ -59,8 +62,8 @@ function notifier_run(&$argv, &$argc){
 	require_once('include/items.php');
 	require_once('include/bbcode.php');
 	require_once('include/email.php');
-	load_config('config');
-	load_config('system');
+
+	Config::load();
 
 	load_hooks();
 
diff --git a/include/onepoll.php b/include/onepoll.php
index d92cb915b6..5219d9f3bd 100644
--- a/include/onepoll.php
+++ b/include/onepoll.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/follow.php");
 
@@ -32,8 +34,7 @@ function onepoll_run(&$argv, &$argc){
 	require_once('include/socgraph.php');
 	require_once('include/queue_fn.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/include/pgettext.php b/include/pgettext.php
index fb87798ff7..335869eda2 100644
--- a/include/pgettext.php
+++ b/include/pgettext.php
@@ -10,6 +10,8 @@
  *
  */
 
+use \Friendica\Core\Config;
+
 require_once("include/dba.php");
 
 if(! function_exists('get_browser_language')) {
@@ -47,12 +49,12 @@ function get_browser_language() {
 			break;
 		}
 	}
-	if(isset($preferred))
+	if (isset($preferred)) {
 		return $preferred;
+	}
 
 	// in case none matches, get the system wide configured language, or fall back to English
-    $a = get_app();
-	return ((isset($a->config['system']['language'])) ? $a->config['system']['language'] : 'en');
+	return Config::get('system', 'language', 'en');
 }}
 
 
diff --git a/include/photos.php b/include/photos.php
index 7cdd14bf6d..9d8d3309c2 100644
--- a/include/photos.php
+++ b/include/photos.php
@@ -49,7 +49,7 @@ function photo_albums($uid, $update = false) {
 			/// @todo This query needs to be renewed. It is really slow
 			// At this time we just store the data in the cache
 			$albums = qu("SELECT COUNT(DISTINCT `resource-id`) AS `total`, `album`
-				FROM `photo` USE INDEX (`uid_album_created`)
+				FROM `photo`
 				WHERE `uid` = %d  AND `album` != '%s' AND `album` != '%s' $sql_extra
 				GROUP BY `album` ORDER BY `created` DESC",
 				intval($uid),
@@ -59,7 +59,7 @@ function photo_albums($uid, $update = false) {
 		} else {
 			// This query doesn't do the count and is much faster
 			$albums = qu("SELECT DISTINCT(`album`), '' AS `total`
-				FROM `photo` USE INDEX (`uid_album_created`)
+				FROM `photo`
 				WHERE `uid` = %d  AND `album` != '%s' AND `album` != '%s' $sql_extra
 				GROUP BY `album` ORDER BY `created` DESC",
 				intval($uid),
diff --git a/include/plaintext.php b/include/plaintext.php
index 632abf30cb..6ab4ec77d6 100644
--- a/include/plaintext.php
+++ b/include/plaintext.php
@@ -272,12 +272,13 @@ function shortenmsg($msg, $limit, $twitter = false) {
 	$lines = explode("\n", $msg);
 	$msg = "";
 	$recycle = html_entity_decode("&#x2672; ", ENT_QUOTES, 'UTF-8');
+	$ellipsis = html_entity_decode("&#x2026;", ENT_QUOTES, 'UTF-8');
 	foreach ($lines AS $row=>$line) {
 		if (iconv_strlen(trim($msg."\n".$line), "UTF-8") <= $limit)
 			$msg = trim($msg."\n".$line);
 		// Is the new message empty by now or is it a reshared message?
 		elseif (($msg == "") OR (($row == 1) AND (substr($msg, 0, 4) == $recycle)))
-			$msg = iconv_substr(iconv_substr(trim($msg."\n".$line), 0, $limit, "UTF-8"), 0, -3, "UTF-8")."...";
+			$msg = iconv_substr(iconv_substr(trim($msg."\n".$line), 0, $limit, "UTF-8"), 0, -3, "UTF-8").$ellipsis;
 		else
 			break;
 	}
diff --git a/include/poller.php b/include/poller.php
index b631d2acd1..e8bfb88389 100644
--- a/include/poller.php
+++ b/include/poller.php
@@ -30,8 +30,9 @@ function poller_run($argv, $argc){
 	};
 
 	// Quit when in maintenance
-	if (get_config('system', 'maintenance', true))
+	if (Config::get('system', 'maintenance', true)) {
 		return;
+	}
 
 	$a->start_process();
 
@@ -90,10 +91,8 @@ function poller_execute($queue) {
 
 	$mypid = getmypid();
 
-	$cooldown = Config::get("system", "worker_cooldown", 0);
-
 	// Quit when in maintenance
-	if (get_config('system', 'maintenance', true)) {
+	if (Config::get('system', 'maintenance', true)) {
 		return false;
 	}
 
@@ -137,8 +136,6 @@ function poller_execute($queue) {
 
 	$argv = json_decode($queue["parameter"]);
 
-	$argc = count($argv);
-
 	// Check for existance and validity of the include file
 	$include = $argv[0];
 
@@ -153,23 +150,8 @@ function poller_execute($queue) {
 	$funcname = str_replace(".php", "", basename($argv[0]))."_run";
 
 	if (function_exists($funcname)) {
-		logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
 
-		// For better logging create a new process id for every worker call
-		// But preserve the old one for the worker
-		$old_process_id = $a->process_id;
-		$a->process_id = uniqid("wrk", true);
-
-		$funcname($argv, $argc);
-
-		$a->process_id = $old_process_id;
-
-		if ($cooldown > 0) {
-			logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
-			sleep($cooldown);
-		}
-
-		logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done");
+		poller_exec_function($queue, $funcname, $argv);
 
 		q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($queue["id"]));
 	} else {
@@ -179,6 +161,104 @@ function poller_execute($queue) {
 	return true;
 }
 
+/**
+ * @brief Execute a function from the queue
+ *
+ * @param array $queue Workerqueue entry
+ * @param string $funcname name of the function
+ * @param array $argv Array of values to be passed to the function
+ */
+function poller_exec_function($queue, $funcname, $argv) {
+
+	$a = get_app();
+
+	$mypid = getmypid();
+
+	$argc = count($argv);
+
+	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
+
+	$stamp = (float)microtime(true);
+
+	// We use the callstack here to analyze the performance of executed worker entries.
+	// For this reason the variables have to be initialized.
+	if (Config::get("system", "profiler")) {
+		$a->performance["start"] = microtime(true);
+		$a->performance["database"] = 0;
+		$a->performance["database_write"] = 0;
+		$a->performance["network"] = 0;
+		$a->performance["file"] = 0;
+		$a->performance["rendering"] = 0;
+		$a->performance["parser"] = 0;
+		$a->performance["marktime"] = 0;
+		$a->performance["markstart"] = microtime(true);
+		$a->callstack = array();
+	}
+
+	// For better logging create a new process id for every worker call
+	// But preserve the old one for the worker
+	$old_process_id = $a->process_id;
+	$a->process_id = uniqid("wrk", true);
+
+	$funcname($argv, $argc);
+
+	$a->process_id = $old_process_id;
+
+	$duration = number_format(microtime(true) - $stamp, 3);
+
+	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
+
+	// Write down the performance values into the log
+	if (Config::get("system", "profiler")) {
+		$duration = microtime(true)-$a->performance["start"];
+
+		if (Config::get("rendertime", "callstack")) {
+			if (isset($a->callstack["database"])) {
+				$o = "\nDatabase Read:\n";
+				foreach ($a->callstack["database"] AS $func => $time) {
+					$time = round($time, 3);
+					if ($time > 0)
+						$o .= $func.": ".$time."\n";
+				}
+			}
+			if (isset($a->callstack["database_write"])) {
+				$o .= "\nDatabase Write:\n";
+				foreach ($a->callstack["database_write"] AS $func => $time) {
+					$time = round($time, 3);
+					if ($time > 0)
+						$o .= $func.": ".$time."\n";
+				}
+			}
+			if (isset($a->callstack["network"])) {
+				$o .= "\nNetwork:\n";
+				foreach ($a->callstack["network"] AS $func => $time) {
+					$time = round($time, 3);
+					if ($time > 0)
+						$o .= $func.": ".$time."\n";
+				}
+			}
+		} else {
+			$o = '';
+		}
+
+		logger("ID ".$queue["id"].": ".$funcname.": ".sprintf("DB: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
+			number_format($a->performance["database"] - $a->performance["database_write"], 2),
+			number_format($a->performance["database_write"], 2),
+			number_format($a->performance["network"], 2),
+			number_format($a->performance["file"], 2),
+			number_format($duration - ($a->performance["database"] + $a->performance["network"] + $a->performance["file"]), 2),
+			number_format($duration, 2)),
+			LOGGER_DEBUG);
+	}
+
+	$cooldown = Config::get("system", "worker_cooldown", 0);
+
+	if ($cooldown > 0) {
+		logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
+		sleep($cooldown);
+	}
+}
+
 /**
  * @brief Checks if the number of database connections has reached a critical limit.
  *
@@ -187,7 +267,7 @@ function poller_execute($queue) {
 function poller_max_connections_reached() {
 
 	// Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
-	$max = get_config("system", "max_connections");
+	$max = Config::get("system", "max_connections");
 
 	// Fetch the percentage level where the poller will get active
 	$maxlevel = Config::get("system", "max_connections_level", 75);
@@ -371,7 +451,7 @@ function poller_too_much_workers() {
 		logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries." (".$processlist.") - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 
 		// Are there fewer workers running as possible? Then fork a new one.
-		if (!get_config("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
+		if (!Config::get("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 			logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 			$args = array("php", "include/poller.php", "no_cron");
 			$a = get_app();
@@ -500,7 +580,7 @@ function call_worker_if_idle() {
 	if (function_exists("proc_open")) {
 		// When was the last time that we called the worker?
 		// Less than one minute? Then we quit
-		if ((time() - get_config("system", "worker_started")) < 60) {
+		if ((time() - Config::get("system", "worker_started")) < 60) {
 			return;
 		}
 
diff --git a/include/post_update.php b/include/post_update.php
index b2d682d722..f9649961d9 100644
--- a/include/post_update.php
+++ b/include/post_update.php
@@ -239,7 +239,7 @@ function post_update_1206() {
 
 	logger("Start", LOGGER_DEBUG);
 	$r = q("SELECT `contact`.`id`, `contact`.`last-item`,
-		(SELECT MAX(`changed`) FROM `item` FORCE INDEX (`uid_wall_changed`) WHERE `wall` AND `uid` = `user`.`uid`) AS `lastitem_date`
+		(SELECT MAX(`changed`) FROM `item` USE INDEX (`uid_wall_changed`) WHERE `wall` AND `uid` = `user`.`uid`) AS `lastitem_date`
 		FROM `user`
 		INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid` AND `contact`.`self`");
 
diff --git a/include/pubsubpublish.php b/include/pubsubpublish.php
index 6bd90bfc21..428103a971 100644
--- a/include/pubsubpublish.php
+++ b/include/pubsubpublish.php
@@ -72,8 +72,7 @@ function pubsubpublish_run(&$argv, &$argc){
 
 	require_once('include/items.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	// Don't check this stuff if the function is called by the poller
 	if (App::callstack() != "poller_run") {
diff --git a/include/queue.php b/include/queue.php
index f36e7723cd..bcd32985db 100644
--- a/include/queue.php
+++ b/include/queue.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once('include/queue_fn.php');
 require_once('include/dfrn.php');
@@ -23,8 +26,7 @@ function queue_run(&$argv, &$argc){
 	require_once('include/bbcode.php');
 	require_once('include/socgraph.php');
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	// Don't check this stuff if the function is called by the poller
 	if (App::callstack() != "poller_run")
diff --git a/include/remove_contact.php b/include/remove_contact.php
index ec8b83eab9..aa20621116 100644
--- a/include/remove_contact.php
+++ b/include/remove_contact.php
@@ -3,6 +3,9 @@
  * @file include/remove_contact.php
  * @brief Removes orphaned data from deleted contacts
  */
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 
 function remove_contact_run($argv, $argc) {
@@ -19,8 +22,7 @@ function remove_contact_run($argv, $argc) {
 		unset($db_host, $db_user, $db_pass, $db_data);
 	}
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	if ($argc != 2) {
 		return;
diff --git a/include/session.php b/include/session.php
index 31024060f3..055bfcb4ef 100644
--- a/include/session.php
+++ b/include/session.php
@@ -64,8 +64,9 @@ function ref_session_write($id, $data) {
 	$default_expire = time() + 300;
 
 	$memcache = cache::memcache();
-	if (is_object($memcache)) {
-		$memcache->set(get_app()->get_hostname().":session:".$id, $data, MEMCACHE_COMPRESSED, $expire);
+	$a = get_app();
+	if (is_object($memcache) AND is_object($a)) {
+		$memcache->set($a->get_hostname().":session:".$id, $data, MEMCACHE_COMPRESSED, $expire);
 		return true;
 	}
 
diff --git a/include/shadowupdate.php b/include/shadowupdate.php
index 74c2a43ebd..83a785fe1f 100644
--- a/include/shadowupdate.php
+++ b/include/shadowupdate.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/threads.php");
 
@@ -14,8 +17,7 @@ if(is_null($db)) {
 	unset($db_host, $db_user, $db_pass, $db_data);
 }
 
-load_config('config');
-load_config('system');
+Config::load();
 
 update_shadow_copy();
 killme();
diff --git a/include/socgraph.php b/include/socgraph.php
index 6249f189e9..32c151c043 100644
--- a/include/socgraph.php
+++ b/include/socgraph.php
@@ -1529,7 +1529,7 @@ function get_gcontact_id($contact) {
 	if (in_array($contact["network"], array(NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS)))
 		$contact["url"] = clean_contact_url($contact["url"]);
 
-	$r = q("SELECT `id`, `last_contact`, `last_failure`, `network` FROM `gcontact` WHERE `nurl` = '%s' ORDER BY `id` LIMIT 2",
+	$r = q("SELECT `id`, `last_contact`, `last_failure`, `network` FROM `gcontact` WHERE `nurl` = '%s' LIMIT 2",
 		dbesc(normalise_link($contact["url"])));
 
 	if ($r) {
diff --git a/include/spool_post.php b/include/spool_post.php
index c42928a672..d55b100eda 100644
--- a/include/spool_post.php
+++ b/include/spool_post.php
@@ -3,6 +3,9 @@
  * @file include/spool_post.php
  * @brief Posts items that wer spooled because they couldn't be posted.
  */
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/items.php");
 
@@ -20,8 +23,7 @@ function spool_post_run($argv, $argc) {
 		unset($db_host, $db_user, $db_pass, $db_data);
 	}
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$path = get_spoolpath();
 
diff --git a/include/tagupdate.php b/include/tagupdate.php
index b12e809772..b4de121e9f 100644
--- a/include/tagupdate.php
+++ b/include/tagupdate.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/tags.php");
 
@@ -14,8 +17,7 @@ if(is_null($db)) {
 	unset($db_host, $db_user, $db_pass, $db_data);
 }
 
-load_config('config');
-load_config('system');
+Config::load();
 
 update_items();
 killme();
diff --git a/include/threadupdate.php b/include/threadupdate.php
index e9d9bf6e6b..dc528c6b87 100644
--- a/include/threadupdate.php
+++ b/include/threadupdate.php
@@ -1,4 +1,7 @@
 <?php
+
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 require_once("include/threads.php");
 
@@ -14,8 +17,7 @@ if(is_null($db)) {
 	unset($db_host, $db_user, $db_pass, $db_data);
 }
 
-load_config('config');
-load_config('system');
+Config::load();
 
 update_threads();
 update_threads_mention();
diff --git a/include/update_gcontact.php b/include/update_gcontact.php
index 88e1817f0b..6aa8bcac29 100644
--- a/include/update_gcontact.php
+++ b/include/update_gcontact.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 
 function update_gcontact_run(&$argv, &$argc){
@@ -19,8 +21,7 @@ function update_gcontact_run(&$argv, &$argc){
 	require_once('include/Scrape.php');
 	require_once("include/socgraph.php");
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	$a->set_baseurl(get_config('system','url'));
 
diff --git a/index.php b/index.php
index f05151757b..7408f495cd 100644
--- a/index.php
+++ b/index.php
@@ -13,6 +13,8 @@
  *
  */
 
+use \Friendica\Core\Config;
+
 require_once('boot.php');
 require_once('object/BaseObject.php');
 
@@ -54,8 +56,7 @@ if(!$install) {
 	 * Load configs from db. Overwrite configs from .htconfig.php
 	 */
 
-	load_config('config');
-	load_config('system');
+	Config::load();
 
 	if ($a->max_processes_reached() OR $a->maxload_reached()) {
 		header($_SERVER["SERVER_PROTOCOL"].' 503 Service Temporarily Unavailable');
diff --git a/mod/admin.php b/mod/admin.php
index b1bc96fd4f..13a00ff6aa 100644
--- a/mod/admin.php
+++ b/mod/admin.php
@@ -6,6 +6,7 @@
  * @brief Friendica admin
  */
 
+use \Friendica\Core\Config;
 
 require_once("include/enotify.php");
 require_once("include/text.php");
@@ -948,6 +949,16 @@ function admin_page_site(App $a) {
 
 	$diaspora_able = ($a->get_path() == "");
 
+	$optimize_max_tablesize = Config::get('system','optimize_max_tablesize', 100);
+
+	if ($optimize_max_tablesize < -1) {
+		$optimize_max_tablesize = -1;
+	}
+
+	if ($optimize_max_tablesize == 0) {
+		$optimize_max_tablesize = 100;
+	}
+
 	$t = get_markup_template("admin_site.tpl");
 	return replace_macros($t, array(
 		'$title' => t('Administration'),
@@ -1019,7 +1030,7 @@ function admin_page_site(App $a) {
 		'$poll_interval'	=> array('poll_interval', t("Poll interval"), (x(get_config('system','poll_interval'))?get_config('system','poll_interval'):2), t("Delay background polling processes by this many seconds to reduce system load. If 0, use delivery interval.")),
 		'$maxloadavg'		=> array('maxloadavg', t("Maximum Load Average"), ((intval(get_config('system','maxloadavg')) > 0)?get_config('system','maxloadavg'):50), t("Maximum system load before delivery and poll processes are deferred - default 50.")),
 		'$maxloadavg_frontend'	=> array('maxloadavg_frontend', t("Maximum Load Average (Frontend)"), ((intval(get_config('system','maxloadavg_frontend')) > 0)?get_config('system','maxloadavg_frontend'):50), t("Maximum system load before the frontend quits service - default 50.")),
-		'$optimize_max_tablesize'=> array('optimize_max_tablesize', t("Maximum table size for optimization"), ((intval(get_config('system','optimize_max_tablesize')) > 0)?get_config('system','optimize_max_tablesize'):100), t("Maximum table size (in MB) for the automatic optimization - default 100 MB. Enter -1 to disable it.")),
+		'$optimize_max_tablesize'=> array('optimize_max_tablesize', t("Maximum table size for optimization"), $optimize_max_tablesize, t("Maximum table size (in MB) for the automatic optimization - default 100 MB. Enter -1 to disable it.")),
 		'$optimize_fragmentation'=> array('optimize_fragmentation', t("Minimum level of fragmentation"), ((intval(get_config('system','optimize_fragmentation')) > 0)?get_config('system','optimize_fragmentation'):30), t("Minimum fragmenation level to start the automatic optimization - default value is 30%.")),
 
 		'$poco_completion'	=> array('poco_completion', t("Periodical check of global contacts"), get_config('system','poco_completion'), t("If enabled, the global contacts are checked periodically for missing or outdated data and the vitality of the contacts and servers.")),
diff --git a/mod/dfrn_confirm.php b/mod/dfrn_confirm.php
index 57ddc58f2c..e2ce806275 100644
--- a/mod/dfrn_confirm.php
+++ b/mod/dfrn_confirm.php
@@ -224,9 +224,7 @@ function dfrn_confirm_post(App $a, $handsfree = null) {
 			 *
 			 */
 
-			$a->config['system']['curl_timeout'] = 120;
-
-			$res = post_url($dfrn_confirm,$params);
+			$res = post_url($dfrn_confirm, $params, null, $redirects, 120);
 
 			logger(' Confirm: received data: ' . $res, LOGGER_DATA);
 
diff --git a/mod/fetch.php b/mod/fetch.php
index 3576384f01..b87fc0e8e0 100644
--- a/mod/fetch.php
+++ b/mod/fetch.php
@@ -42,7 +42,7 @@ function fetch_init(App $a) {
 
 	// Fetch some data from the author (We could combine both queries - but I think this is more readable)
 	$r = q("SELECT `user`.`prvkey`, `contact`.`addr`, `user`.`nickname`, `contact`.`nick` FROM `user`
-		INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid`
+		INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid` AND `contact`.`self`
 		WHERE `user`.`uid` = %d", intval($item[0]["uid"]));
 	if (!$r) {
 		header($_SERVER["SERVER_PROTOCOL"].' 404 '.t('Not Found'));
diff --git a/mod/friendica.php b/mod/friendica.php
index 3f242f7c56..f613dfd39c 100644
--- a/mod/friendica.php
+++ b/mod/friendica.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 function friendica_init(App $a) {
 	if ($a->argv[1]=="json"){
 		$register_policy = Array('REGISTER_CLOSED', 'REGISTER_APPROVE', 'REGISTER_OPEN');
@@ -29,7 +31,7 @@ function friendica_init(App $a) {
 					$visible_plugins[] = $rr['name'];
 		}
 
-		load_config('feature_lock');
+		Config::load('feature_lock');
 		$locked_features = array();
 		if(is_array($a->config['feature_lock']) && count($a->config['feature_lock'])) {
 			foreach($a->config['feature_lock'] as $k => $v) {
diff --git a/mod/network.php b/mod/network.php
index 2f33c62f72..ad0347ba0c 100644
--- a/mod/network.php
+++ b/mod/network.php
@@ -762,24 +762,23 @@ function network_content(App $a, $update = 0) {
 // on they just get buried deeper. It has happened to me a couple of times also.
 
 
-	if((! $group) && (! $cid) && (! $star)) {
+	if (!$group && !$cid && !$star) {
 
-		$unseen = q("SELECT `id` FROM `item` WHERE `unseen` AND `uid` = %d",
+		$unseen = q("SELECT `id` FROM `item` WHERE `unseen` AND `uid` = %d LIMIT 1",
 				intval(local_user()));
 
-		if ($unseen)
+		if (dbm::is_result($unseen)) {
 			$r = q("UPDATE `item` SET `unseen` = 0
 				WHERE `unseen` = 1 AND `uid` = %d",
 				intval(local_user())
 			);
-	}
-	else {
-		if($update_unseen) {
+		}
+	} elseif ($update_unseen) {
 
-			$unseen = q("SELECT `id` FROM `item` ".$update_unseen);
+		$unseen = q("SELECT `id` FROM `item` ".$update_unseen. " LIMIT 1");
 
-			if ($unseen)
-				$r = q("UPDATE `item` SET `unseen` = 0 $update_unseen");
+		if (dbm::is_result($unseen)) {
+			$r = q("UPDATE `item` SET `unseen` = 0 $update_unseen");
 		}
 	}
 
@@ -790,10 +789,10 @@ function network_content(App $a, $update = 0) {
 
 	$o .= conversation($a,$items,$mode,$update);
 
-	if(!$update) {
-		if(get_pconfig(local_user(),'system','infinite_scroll')) {
+	if (!$update) {
+		if (get_pconfig(local_user(),'system','infinite_scroll')) {
 			$o .= scroll_loader();
-		} elseif(!get_config('system', 'old_pager')) {
+		} elseif (!get_config('system', 'old_pager')) {
 			$o .= alt_pager($a,count($items));
 		} else {
 			$o .= paginate($a);
diff --git a/mod/p.php b/mod/p.php
index 8755464519..3cd7a9eb7d 100644
--- a/mod/p.php
+++ b/mod/p.php
@@ -46,7 +46,7 @@ function p_init($a){
 
 	// Fetch some data from the author (We could combine both queries - but I think this is more readable)
 	$r = q("SELECT `user`.`prvkey`, `contact`.`addr`, `user`.`nickname`, `contact`.`nick` FROM `user`
-		INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid`
+		INNER JOIN `contact` ON `contact`.`uid` = `user`.`uid` AND `contact`.`self`
 		WHERE `user`.`uid` = %d", intval($item[0]["uid"]));
 	if (!dbm::is_result($r)) {
 		header($_SERVER["SERVER_PROTOCOL"].' 404 '.t('Not Found'));
diff --git a/mod/photos.php b/mod/photos.php
index 60e5dee643..af4c60b268 100644
--- a/mod/photos.php
+++ b/mod/photos.php
@@ -10,6 +10,8 @@ require_once('include/tags.php');
 require_once('include/threads.php');
 require_once('include/Probe.php');
 
+use \Friendica\Core\Config;
+
 function photos_init(App $a) {
 
 	if ($a->argc > 1)
@@ -1339,35 +1341,38 @@ function photos_content(App $a) {
 		$prevlink = '';
 		$nextlink = '';
 
-		if ($_GET['order'] === 'posted')
-			$order = 'ASC';
-		else
-			$order = 'DESC';
+		/// @todo This query is totally bad, the whole functionality has to be changed
+		// The query leads to a really intense used index.
+		// By now we hide it if someone wants to.
+		if (!Config::get('system', 'no_count', false)) {
+			if ($_GET['order'] === 'posted')
+				$order = 'ASC';
+			else
+				$order = 'DESC';
 
+			$prvnxt = qu("SELECT `resource-id` FROM `photo` WHERE `album` = '%s' AND `uid` = %d AND `scale` = 0
+				$sql_extra ORDER BY `created` $order ",
+				dbesc($ph[0]['album']),
+				intval($owner_uid)
+			);
 
-		$prvnxt = qu("SELECT `resource-id` FROM `photo` WHERE `album` = '%s' AND `uid` = %d AND `scale` = 0
-			$sql_extra ORDER BY `created` $order ",
-			dbesc($ph[0]['album']),
-			intval($owner_uid)
-		);
-
-		if (count($prvnxt)) {
-			for($z = 0; $z < count($prvnxt); $z++) {
-				if ($prvnxt[$z]['resource-id'] == $ph[0]['resource-id']) {
-					$prv = $z - 1;
-					$nxt = $z + 1;
-					if ($prv < 0)
-						$prv = count($prvnxt) - 1;
-					if ($nxt >= count($prvnxt))
-						$nxt = 0;
-					break;
+			if (count($prvnxt)) {
+				for($z = 0; $z < count($prvnxt); $z++) {
+					if ($prvnxt[$z]['resource-id'] == $ph[0]['resource-id']) {
+						$prv = $z - 1;
+						$nxt = $z + 1;
+						if ($prv < 0)
+							$prv = count($prvnxt) - 1;
+						if ($nxt >= count($prvnxt))
+							$nxt = 0;
+						break;
+					}
 				}
-			}
-			$edit_suffix = ((($cmd === 'edit') && ($can_post)) ? '/edit' : '');
-			$prevlink = 'photos/' . $a->data['user']['nickname'] . '/image/' . $prvnxt[$prv]['resource-id'] . $edit_suffix . (($_GET['order'] === 'posted') ? '?f=&order=posted' : '');
-			$nextlink = 'photos/' . $a->data['user']['nickname'] . '/image/' . $prvnxt[$nxt]['resource-id'] . $edit_suffix . (($_GET['order'] === 'posted') ? '?f=&order=posted' : '');
- 		}
-
+				$edit_suffix = ((($cmd === 'edit') && ($can_post)) ? '/edit' : '');
+				$prevlink = 'photos/' . $a->data['user']['nickname'] . '/image/' . $prvnxt[$prv]['resource-id'] . $edit_suffix . (($_GET['order'] === 'posted') ? '?f=&order=posted' : '');
+				$nextlink = 'photos/' . $a->data['user']['nickname'] . '/image/' . $prvnxt[$nxt]['resource-id'] . $edit_suffix . (($_GET['order'] === 'posted') ? '?f=&order=posted' : '');
+ 			}
+		}
 
 		if (count($ph) == 1)
 			$hires = $lores = $ph[0];
diff --git a/mod/ping.php b/mod/ping.php
index cde03969f4..b5330c7b33 100644
--- a/mod/ping.php
+++ b/mod/ping.php
@@ -5,6 +5,7 @@ require_once('include/ForumManager.php');
 require_once('include/group.php');
 require_once('mod/proxy.php');
 require_once('include/xml.php');
+require_once('include/cache.php');
 
 /**
  * @brief Outputs the counts and the lists of various notifications
@@ -195,13 +196,20 @@ function ping_init(App $a)
 			}
 		}
 
-		$ev = qu("SELECT count(`event`.`id`) AS total, type, start, adjust FROM `event`
-			WHERE `event`.`uid` = %d AND `start` < '%s' AND `finish` > '%s' and `ignore` = 0
-			ORDER BY `start` ASC ",
-			intval(local_user()),
-			dbesc(datetime_convert('UTC', 'UTC', 'now + 7 days')),
-			dbesc(datetime_convert('UTC', 'UTC', 'now'))
-		);
+		$cachekey = "ping_init:".local_user();
+		$ev = Cache::get($cachekey);
+		if (is_null($ev)) {
+			$ev = qu("SELECT count(`event`.`id`) AS total, type, start, adjust FROM `event`
+				WHERE `event`.`uid` = %d AND `start` < '%s' AND `finish` > '%s' and `ignore` = 0
+				ORDER BY `start` ASC ",
+				intval(local_user()),
+				dbesc(datetime_convert('UTC', 'UTC', 'now + 7 days')),
+				dbesc(datetime_convert('UTC', 'UTC', 'now'))
+			);
+			if (dbm::is_result($ev)) {
+				Cache::set($cachekey, $ev, CACHE_HOUR);
+			}
+		}
 
 		if (dbm::is_result($ev)) {
 			$all_events = intval($ev[0]['total']);
diff --git a/update.php b/update.php
index 058536d821..25d6cb9cbf 100644
--- a/update.php
+++ b/update.php
@@ -1,6 +1,6 @@
 <?php
 
-define('UPDATE_VERSION' , 1212);
+define('UPDATE_VERSION' , 1213);
 
 /**
  *
diff --git a/util/maintenance.php b/util/maintenance.php
index d1ff94524e..28f3a503ad 100644
--- a/util/maintenance.php
+++ b/util/maintenance.php
@@ -1,5 +1,7 @@
 <?php
 
+use \Friendica\Core\Config;
+
 require_once("boot.php");
 
 $a = new App;
@@ -10,9 +12,9 @@ load_translation_table($lang);
 
 require_once("include/dba.php");
 $db = new dba($db_host, $db_user, $db_pass, $db_data, false);
-        unset($db_host, $db_user, $db_pass, $db_data);
-load_config('config');
-load_config('system');
+unset($db_host, $db_user, $db_pass, $db_data);
+
+Config::load();
 
 $maint_mode = 1;
 if($argc > 1)