Update to MediaWiki 1.25.1

15 files changed, 140 insertions, 1036 deletions

diff --git a/includes/objectcache/APCBagOStuff.php b/includes/objectcache/APCBagOStuff.php
deleted file mode 100644
index 4cbb32df..00000000
--- a/includes/objectcache/APCBagOStuff.php
+++ /dev/null
@@ -1,108 +0,0 @@
-<?php
-/**
- * Object caching using PHP's APC accelerator.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * This is a wrapper for APC's shared memory functions
- *
- * @ingroup Cache
- */
-class APCBagOStuff extends BagOStuff {
-	/**
-	 * @param string $key
-	 * @param int $casToken [optional]
-	 * @return mixed
-	 */
-	public function get( $key, &$casToken = null ) {
-		$val = apc_fetch( $key );
-
-		$casToken = $val;
-
-		if ( is_string( $val ) ) {
-			if ( $this->isInteger( $val ) ) {
-				$val = intval( $val );
-			} else {
-				$val = unserialize( $val );
-			}
-		}
-
-		return $val;
-	}
-
-	/**
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool
-	 */
-	public function set( $key, $value, $exptime = 0 ) {
-		if ( !$this->isInteger( $value ) ) {
-			$value = serialize( $value );
-		}
-
-		apc_store( $key, $value, $exptime );
-
-		return true;
-	}
-
-	/**
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool
-	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
-		// APC's CAS functions only work on integers
-		throw new MWException( "CAS is not implemented in " . __CLASS__ );
-	}
-
-	/**
-	 * @param string $key
-	 * @param int $time
-	 * @return bool
-	 */
-	public function delete( $key, $time = 0 ) {
-		apc_delete( $key );
-
-		return true;
-	}
-
-	/**
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	public function merge( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		return $this->mergeViaLock( $key, $callback, $exptime, $attempts );
-	}
-
-	public function incr( $key, $value = 1 ) {
-		return apc_inc( $key, $value );
-	}
-
-	public function decr( $key, $value = 1 ) {
-		return apc_dec( $key, $value );
-	}
-}
diff --git a/includes/objectcache/BagOStuff.php b/includes/objectcache/BagOStuff.php
deleted file mode 100644
index 1978c3ea..00000000
--- a/includes/objectcache/BagOStuff.php
+++ /dev/null
@@ -1,406 +0,0 @@
-<?php
-/**
- * Classes to cache objects in PHP accelerators, SQL database or DBA files
- *
- * Copyright © 2003-2004 Brion Vibber <brion@pobox.com>
- * https://www.mediawiki.org/
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * @defgroup Cache Cache
- */
-
-/**
- * interface is intended to be more or less compatible with
- * the PHP memcached client.
- *
- * backends for local hash array and SQL table included:
- * <code>
- *   $bag = new HashBagOStuff();
- *   $bag = new SqlBagOStuff(); # connect to db first
- * </code>
- *
- * @ingroup Cache
- */
-abstract class BagOStuff {
-	private $debugMode = false;
-
-	protected $lastError = self::ERR_NONE;
-
-	/** Possible values for getLastError() */
-	const ERR_NONE = 0; // no error
-	const ERR_NO_RESPONSE = 1; // no response
-	const ERR_UNREACHABLE = 2; // can't connect
-	const ERR_UNEXPECTED = 3; // response gave some error
-
-	/**
-	 * @param bool $bool
-	 */
-	public function setDebug( $bool ) {
-		$this->debugMode = $bool;
-	}
-
-	/* *** THE GUTS OF THE OPERATION *** */
-	/* Override these with functional things in subclasses */
-
-	/**
-	 * Get an item with the given key. Returns false if it does not exist.
-	 * @param string $key
-	 * @param mixed $casToken [optional]
-	 * @return mixed Returns false on failure
-	 */
-	abstract public function get( $key, &$casToken = null );
-
-	/**
-	 * Set an item.
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @return bool Success
-	 */
-	abstract public function set( $key, $value, $exptime = 0 );
-
-	/**
-	 * Check and set an item.
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @return bool Success
-	 */
-	abstract public function cas( $casToken, $key, $value, $exptime = 0 );
-
-	/**
-	 * Delete an item.
-	 * @param string $key
-	 * @param int $time Amount of time to delay the operation (mostly memcached-specific)
-	 * @return bool True if the item was deleted or not found, false on failure
-	 */
-	abstract public function delete( $key, $time = 0 );
-
-	/**
-	 * Merge changes into the existing cache value (possibly creating a new one).
-	 * The callback function returns the new value given the current value (possibly false),
-	 * and takes the arguments: (this BagOStuff object, cache key, current value).
-	 *
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	public function merge( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
-	}
-
-	/**
-	 * @see BagOStuff::merge()
-	 *
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	protected function mergeViaCas( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		do {
-			$casToken = null; // passed by reference
-			$currentValue = $this->get( $key, $casToken ); // get the old value
-			$value = $callback( $this, $key, $currentValue ); // derive the new value
-
-			if ( $value === false ) {
-				$success = true; // do nothing
-			} elseif ( $currentValue === false ) {
-				// Try to create the key, failing if it gets created in the meantime
-				$success = $this->add( $key, $value, $exptime );
-			} else {
-				// Try to update the key, failing if it gets changed in the meantime
-				$success = $this->cas( $casToken, $key, $value, $exptime );
-			}
-		} while ( !$success && --$attempts );
-
-		return $success;
-	}
-
-	/**
-	 * @see BagOStuff::merge()
-	 *
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	protected function mergeViaLock( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		if ( !$this->lock( $key, 6 ) ) {
-			return false;
-		}
-
-		$currentValue = $this->get( $key ); // get the old value
-		$value = $callback( $this, $key, $currentValue ); // derive the new value
-
-		if ( $value === false ) {
-			$success = true; // do nothing
-		} else {
-			$success = $this->set( $key, $value, $exptime ); // set the new value
-		}
-
-		if ( !$this->unlock( $key ) ) {
-			// this should never happen
-			trigger_error( "Could not release lock for key '$key'." );
-		}
-
-		return $success;
-	}
-
-	/**
-	 * @param string $key
-	 * @param int $timeout [optional]
-	 * @return bool Success
-	 */
-	public function lock( $key, $timeout = 6 ) {
-		$this->clearLastError();
-		$timestamp = microtime( true ); // starting UNIX timestamp
-		if ( $this->add( "{$key}:lock", 1, $timeout ) ) {
-			return true;
-		} elseif ( $this->getLastError() ) {
-			return false;
-		}
-
-		$uRTT = ceil( 1e6 * ( microtime( true ) - $timestamp ) ); // estimate RTT (us)
-		$sleep = 2 * $uRTT; // rough time to do get()+set()
-
-		$locked = false; // lock acquired
-		$attempts = 0; // failed attempts
-		do {
-			if ( ++$attempts >= 3 && $sleep <= 1e6 ) {
-				// Exponentially back off after failed attempts to avoid network spam.
-				// About 2*$uRTT*(2^n-1) us of "sleep" happen for the next n attempts.
-				$sleep *= 2;
-			}
-			usleep( $sleep ); // back off
-			$this->clearLastError();
-			$locked = $this->add( "{$key}:lock", 1, $timeout );
-			if ( $this->getLastError() ) {
-				return false;
-			}
-		} while ( !$locked );
-
-		return $locked;
-	}
-
-	/**
-	 * @param string $key
-	 * @return bool Success
-	 */
-	public function unlock( $key ) {
-		return $this->delete( "{$key}:lock" );
-	}
-
-	/**
-	 * Delete all objects expiring before a certain date.
-	 * @param string $date The reference date in MW format
-	 * @param callable|bool $progressCallback Optional, a function which will be called
-	 *     regularly during long-running operations with the percentage progress
-	 *     as the first parameter.
-	 *
-	 * @return bool Success, false if unimplemented
-	 */
-	public function deleteObjectsExpiringBefore( $date, $progressCallback = false ) {
-		// stub
-		return false;
-	}
-
-	/* *** Emulated functions *** */
-
-	/**
-	 * Get an associative array containing the item for each of the keys that have items.
-	 * @param array $keys List of strings
-	 * @return array
-	 */
-	public function getMulti( array $keys ) {
-		$res = array();
-		foreach ( $keys as $key ) {
-			$val = $this->get( $key );
-			if ( $val !== false ) {
-				$res[$key] = $val;
-			}
-		}
-		return $res;
-	}
-
-	/**
-	 * Batch insertion
-	 * @param array $data $key => $value assoc array
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @return bool Success
-	 * @since 1.24
-	 */
-	public function setMulti( array $data, $exptime = 0 ) {
-		$res = true;
-		foreach ( $data as $key => $value ) {
-			if ( !$this->set( $key, $value, $exptime ) ) {
-				$res = false;
-			}
-		}
-		return $res;
-	}
-
-	/**
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool Success
-	 */
-	public function add( $key, $value, $exptime = 0 ) {
-		if ( $this->get( $key ) === false ) {
-			return $this->set( $key, $value, $exptime );
-		}
-		return false; // key already set
-	}
-
-	/**
-	 * Increase stored value of $key by $value while preserving its TTL
-	 * @param string $key Key to increase
-	 * @param int $value Value to add to $key (Default 1)
-	 * @return int|bool New value or false on failure
-	 */
-	public function incr( $key, $value = 1 ) {
-		if ( !$this->lock( $key ) ) {
-			return false;
-		}
-		$n = $this->get( $key );
-		if ( $this->isInteger( $n ) ) { // key exists?
-			$n += intval( $value );
-			$this->set( $key, max( 0, $n ) ); // exptime?
-		} else {
-			$n = false;
-		}
-		$this->unlock( $key );
-
-		return $n;
-	}
-
-	/**
-	 * Decrease stored value of $key by $value while preserving its TTL
-	 * @param string $key
-	 * @param int $value
-	 * @return int
-	 */
-	public function decr( $key, $value = 1 ) {
-		return $this->incr( $key, - $value );
-	}
-
-	/**
-	 * Increase stored value of $key by $value while preserving its TTL
-	 *
-	 * This will create the key with value $init and TTL $ttl if not present
-	 *
-	 * @param string $key
-	 * @param int $ttl
-	 * @param int $value
-	 * @param int $init
-	 * @return bool
-	 * @since 1.24
-	 */
-	public function incrWithInit( $key, $ttl, $value = 1, $init = 1 ) {
-		return $this->incr( $key, $value ) ||
-			$this->add( $key, (int)$init, $ttl ) || $this->incr( $key, $value );
-	}
-
-	/**
-	 * Get the "last error" registered; clearLastError() should be called manually
-	 * @return int ERR_* constant for the "last error" registry
-	 * @since 1.23
-	 */
-	public function getLastError() {
-		return $this->lastError;
-	}
-
-	/**
-	 * Clear the "last error" registry
-	 * @since 1.23
-	 */
-	public function clearLastError() {
-		$this->lastError = self::ERR_NONE;
-	}
-
-	/**
-	 * Set the "last error" registry
-	 * @param int $err ERR_* constant
-	 * @since 1.23
-	 */
-	protected function setLastError( $err ) {
-		$this->lastError = $err;
-	}
-
-	/**
-	 * @param string $text
-	 */
-	public function debug( $text ) {
-		if ( $this->debugMode ) {
-			$class = get_class( $this );
-			wfDebug( "$class debug: $text\n" );
-		}
-	}
-
-	/**
-	 * Convert an optionally relative time to an absolute time
-	 * @param int $exptime
-	 * @return int
-	 */
-	protected function convertExpiry( $exptime ) {
-		if ( ( $exptime != 0 ) && ( $exptime < 86400 * 3650 /* 10 years */ ) ) {
-			return time() + $exptime;
-		} else {
-			return $exptime;
-		}
-	}
-
-	/**
-	 * Convert an optionally absolute expiry time to a relative time. If an
-	 * absolute time is specified which is in the past, use a short expiry time.
-	 *
-	 * @param int $exptime
-	 * @return int
-	 */
-	protected function convertToRelative( $exptime ) {
-		if ( $exptime >= 86400 * 3650 /* 10 years */ ) {
-			$exptime -= time();
-			if ( $exptime <= 0 ) {
-				$exptime = 1;
-			}
-			return $exptime;
-		} else {
-			return $exptime;
-		}
-	}
-
-	/**
-	 * Check if a value is an integer
-	 *
-	 * @param mixed $value
-	 * @return bool
-	 */
-	protected function isInteger( $value ) {
-		return ( is_int( $value ) || ctype_digit( $value ) );
-	}
-}
diff --git a/includes/objectcache/EmptyBagOStuff.php b/includes/objectcache/EmptyBagOStuff.php
deleted file mode 100644
index 9595b83c..00000000
--- a/includes/objectcache/EmptyBagOStuff.php
+++ /dev/null
@@ -1,80 +0,0 @@
-<?php
-/**
- * Dummy object caching.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * A BagOStuff object with no objects in it. Used to provide a no-op object to calling code.
- *
- * @ingroup Cache
- */
-class EmptyBagOStuff extends BagOStuff {
-
-	/**
-	 * @param string $key
-	 * @param mixed $casToken [optional]
-	 * @return bool
-	 */
-	function get( $key, &$casToken = null ) {
-		return false;
-	}
-
-	/**
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exp
-	 * @return bool
-	 */
-	function set( $key, $value, $exp = 0 ) {
-		return true;
-	}
-
-	/**
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exp
-	 * @return bool
-	 */
-	function cas( $casToken, $key, $value, $exp = 0 ) {
-		return true;
-	}
-
-	/**
-	 * @param string $key
-	 * @param int $time
-	 * @return bool
-	 */
-	function delete( $key, $time = 0 ) {
-		return true;
-	}
-
-	/**
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	public function merge( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		return true;
-	}
-}
diff --git a/includes/objectcache/HashBagOStuff.php b/includes/objectcache/HashBagOStuff.php
deleted file mode 100644
index 6e50a8c3..00000000
--- a/includes/objectcache/HashBagOStuff.php
+++ /dev/null
@@ -1,113 +0,0 @@
-<?php
-/**
- * Object caching using PHP arrays.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * This is a test of the interface, mainly. It stores things in an associative
- * array, which is not going to persist between program runs.
- *
- * @ingroup Cache
- */
-class HashBagOStuff extends BagOStuff {
-	/** @var array */
-	protected $bag;
-
-	function __construct() {
-		$this->bag = array();
-	}
-
-	/**
-	 * @param string $key
-	 * @return bool
-	 */
-	protected function expire( $key ) {
-		$et = $this->bag[$key][1];
-
-		if ( ( $et == 0 ) || ( $et > time() ) ) {
-			return false;
-		}
-
-		$this->delete( $key );
-
-		return true;
-	}
-
-	/**
-	 * @param string $key
-	 * @param mixed $casToken [optional]
-	 * @return bool|mixed
-	 */
-	function get( $key, &$casToken = null ) {
-		if ( !isset( $this->bag[$key] ) ) {
-			return false;
-		}
-
-		if ( $this->expire( $key ) ) {
-			return false;
-		}
-
-		$casToken = serialize( $this->bag[$key][0] );
-
-		return $this->bag[$key][0];
-	}
-
-	/**
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool
-	 */
-	function set( $key, $value, $exptime = 0 ) {
-		$this->bag[$key] = array( $value, $this->convertExpiry( $exptime ) );
-		return true;
-	}
-
-	/**
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool
-	 */
-	function cas( $casToken, $key, $value, $exptime = 0 ) {
-		if ( serialize( $this->get( $key ) ) === $casToken ) {
-			return $this->set( $key, $value, $exptime );
-		}
-
-		return false;
-	}
-
-	/**
-	 * @param string $key
-	 * @param int $time
-	 * @return bool
-	 */
-	function delete( $key, $time = 0 ) {
-		if ( !isset( $this->bag[$key] ) ) {
-			return false;
-		}
-
-		unset( $this->bag[$key] );
-
-		return true;
-	}
-}
diff --git a/includes/objectcache/MemcachedBagOStuff.php b/includes/objectcache/MemcachedBagOStuff.php
index 53edcdde..83bee700 100644
--- a/includes/objectcache/MemcachedBagOStuff.php
+++ b/includes/objectcache/MemcachedBagOStuff.php
@@ -84,18 +84,17 @@ class MemcachedBagOStuff extends BagOStuff {
 	 * @param int $exptime
 	 * @return bool
 	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
+	protected function cas( $casToken, $key, $value, $exptime = 0 ) {
 		return $this->client->cas( $casToken, $this->encodeKey( $key ),
 			$value, $this->fixExpiry( $exptime ) );
 	}
 
 	/**
 	 * @param string $key
-	 * @param int $time
 	 * @return bool
 	 */
-	public function delete( $key, $time = 0 ) {
-		return $this->client->delete( $this->encodeKey( $key ), $time );
+	public function delete( $key ) {
+		return $this->client->delete( $this->encodeKey( $key ) );
 	}
 
 	/**
@@ -109,6 +108,14 @@ class MemcachedBagOStuff extends BagOStuff {
 			$this->fixExpiry( $exptime ) );
 	}
 
+	public function merge( $key, $callback, $exptime = 0, $attempts = 10 ) {
+		if ( !is_callable( $callback ) ) {
+			throw new Exception( "Got invalid callback." );
+		}
+
+		return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
+	}
+
 	/**
 	 * Get the underlying client object. This is provided for debugging
 	 * purposes.
@@ -145,7 +152,7 @@ class MemcachedBagOStuff extends BagOStuff {
 	 * TTLs higher than 30 days will be detected as absolute TTLs
 	 * (UNIX timestamps), and will result in the cache entry being
 	 * discarded immediately because the expiry is in the past.
-	 * Clamp expiries >30d at 30d, unless they're >=1e9 in which
+	 * Clamp expires >30d at 30d, unless they're >=1e9 in which
 	 * case they are likely to really be absolute (1e9 = 2011-09-09)
 	 * @param int $expiry
 	 * @return int
@@ -174,6 +181,6 @@ class MemcachedBagOStuff extends BagOStuff {
 	 * @param string $text
 	 */
 	protected function debugLog( $text ) {
-		wfDebugLog( 'memcached', $text );
+		$this->logger->debug( $text );
 	}
 }
diff --git a/includes/objectcache/MemcachedClient.php b/includes/objectcache/MemcachedClient.php
index 41eebfb5..bc4a00b2 100644
--- a/includes/objectcache/MemcachedClient.php
+++ b/includes/objectcache/MemcachedClient.php
@@ -64,6 +64,9 @@
  * @version 0.1.2
  */
 
+use Psr\Log\LoggerInterface;
+use Psr\Log\NullLogger;
+
 // {{{ requirements
 // }}}
 
@@ -233,6 +236,11 @@ class MWMemcached {
 	 */
 	public $_connect_attempts;
 
+	/**
+	 * @var LoggerInterface
+	 */
+	private $_logger;
+
 	// }}}
 	// }}}
 	// {{{ methods
@@ -263,6 +271,8 @@ class MWMemcached {
 
 		$this->_connect_timeout = isset( $args['connect_timeout'] ) ? $args['connect_timeout'] : 0.1;
 		$this->_connect_attempts = 2;
+
+		$this->_logger = isset( $args['logger'] ) ? $args['logger'] : new NullLogger();
 	}
 
 	// }}}
@@ -413,7 +423,6 @@ class MWMemcached {
 	 * @return mixed
 	 */
 	public function get( $key, &$casToken = null ) {
-		wfProfileIn( __METHOD__ );
 
 		if ( $this->_debug ) {
 			$this->_debugprint( "get($key)\n" );
@@ -421,19 +430,16 @@ class MWMemcached {
 
 		if ( !is_array( $key ) && strval( $key ) === '' ) {
 			$this->_debugprint( "Skipping key which equals to an empty string" );
-			wfProfileOut( __METHOD__ );
 			return false;
 		}
 
 		if ( !$this->_active ) {
-			wfProfileOut( __METHOD__ );
 			return false;
 		}
 
 		$sock = $this->get_sock( $key );
 
 		if ( !is_resource( $sock ) ) {
-			wfProfileOut( __METHOD__ );
 			return false;
 		}
 
@@ -446,7 +452,6 @@ class MWMemcached {
 
 		$cmd = "gets $key\r\n";
 		if ( !$this->_fwrite( $sock, $cmd ) ) {
-			wfProfileOut( __METHOD__ );
 			return false;
 		}
 
@@ -463,7 +468,6 @@ class MWMemcached {
 		if ( isset( $val[$key] ) ) {
 			$value = $val[$key];
 		}
-		wfProfileOut( __METHOD__ );
 		return $value;
 	}
 
@@ -1110,14 +1114,14 @@ class MWMemcached {
 	 * @param string $text
 	 */
 	function _debugprint( $text ) {
-		wfDebugLog( 'memcached', $text );
+		$this->_logger->debug( $text );
 	}
 
 	/**
 	 * @param string $text
 	 */
 	function _error_log( $text ) {
-		wfDebugLog( 'memcached-serious', "Memcached error: $text" );
+		$this->_logger->error( "Memcached error: $text" );
 	}
 
 	/**
diff --git a/includes/objectcache/MemcachedPeclBagOStuff.php b/includes/objectcache/MemcachedPeclBagOStuff.php
index c853bcf4..f2c49281 100644
--- a/includes/objectcache/MemcachedPeclBagOStuff.php
+++ b/includes/objectcache/MemcachedPeclBagOStuff.php
@@ -43,8 +43,10 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	 *                          values, but serialization is much slower unless the php.ini option
 	 *                          igbinary.compact_strings is off.
 	 * @param array $params
+	 * @throws MWException
 	 */
 	function __construct( $params ) {
+		parent::__construct( $params );
 		$params = $this->applyDefaultParams( $params );
 
 		if ( $params['persistent'] ) {
@@ -53,7 +55,7 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 			// We can only reuse a pool ID if we keep the config consistent.
 			$this->client = new Memcached( md5( serialize( $params ) ) );
 			if ( count( $this->client->getServerList() ) ) {
-				wfDebug( __METHOD__ . ": persistent Memcached object already loaded.\n" );
+				$this->logger->debug( __METHOD__ . ": persistent Memcached object already loaded." );
 				return; // already initialized; don't add duplicate servers
 			}
 		} else {
@@ -119,11 +121,9 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	 * @return mixed
 	 */
 	public function get( $key, &$casToken = null ) {
-		wfProfileIn( __METHOD__ );
 		$this->debugLog( "get($key)" );
 		$result = $this->client->get( $this->encodeKey( $key ), null, $casToken );
 		$result = $this->checkResult( $key, $result );
-		wfProfileOut( __METHOD__ );
 		return $result;
 	}
 
@@ -145,19 +145,18 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	 * @param int $exptime
 	 * @return bool
 	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
+	protected function cas( $casToken, $key, $value, $exptime = 0 ) {
 		$this->debugLog( "cas($key)" );
 		return $this->checkResult( $key, parent::cas( $casToken, $key, $value, $exptime ) );
 	}
 
 	/**
 	 * @param string $key
-	 * @param int $time
 	 * @return bool
 	 */
-	public function delete( $key, $time = 0 ) {
+	public function delete( $key ) {
 		$this->debugLog( "delete($key)" );
-		$result = parent::delete( $key, $time );
+		$result = parent::delete( $key );
 		if ( $result === false && $this->client->getResultCode() === Memcached::RES_NOTFOUND ) {
 			// "Not found" is counted as success in our interface
 			return true;
@@ -224,14 +223,16 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 				break;
 			default:
 				$msg = $this->client->getResultMessage();
+				$logCtx = array();
 				if ( $key !== false ) {
 					$server = $this->client->getServerByKey( $key );
-					$serverName = "{$server['host']}:{$server['port']}";
-					$msg = "Memcached error for key \"$key\" on server \"$serverName\": $msg";
+					$logCtx['memcached-server'] = "{$server['host']}:{$server['port']}";
+					$logCtx['memcached-key'] = $key;
+					$msg = "Memcached error for key \"{memcached-key}\" on server \"{memcached-server}\": $msg";
 				} else {
 					$msg = "Memcached error: $msg";
 				}
-				wfDebugLog( 'memcached-serious', $msg );
+				$this->logger->error( $msg, $logCtx );
 				$this->setLastError( BagOStuff::ERR_UNEXPECTED );
 		}
 		return $result;
@@ -242,11 +243,9 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	 * @return array
 	 */
 	public function getMulti( array $keys ) {
-		wfProfileIn( __METHOD__ );
 		$this->debugLog( 'getMulti(' . implode( ', ', $keys ) . ')' );
 		$callback = array( $this, 'encodeKey' );
 		$result = $this->client->getMulti( array_map( $callback, $keys ) );
-		wfProfileOut( __METHOD__ );
 		$result = $result ?: array(); // must be an array
 		return $this->checkResult( false, $result );
 	}
@@ -257,7 +256,6 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 	 * @return bool
 	 */
 	public function setMulti( array $data, $exptime = 0 ) {
-		wfProfileIn( __METHOD__ );
 		foreach ( $data as $key => $value ) {
 			$encKey = $this->encodeKey( $key );
 			if ( $encKey !== $key ) {
@@ -267,7 +265,6 @@ class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
 		}
 		$this->debugLog( 'setMulti(' . implode( ', ', array_keys( $data ) ) . ')' );
 		$result = $this->client->setMulti( $data, $this->fixExpiry( $exptime ) );
-		wfProfileOut( __METHOD__ );
 		return $this->checkResult( false, $result );
 	}
 }
diff --git a/includes/objectcache/MemcachedPhpBagOStuff.php b/includes/objectcache/MemcachedPhpBagOStuff.php
index 330d2b52..6fba61ba 100644
--- a/includes/objectcache/MemcachedPhpBagOStuff.php
+++ b/includes/objectcache/MemcachedPhpBagOStuff.php
@@ -42,6 +42,7 @@ class MemcachedPhpBagOStuff extends MemcachedBagOStuff {
 	 * @param array $params
 	 */
 	function __construct( $params ) {
+		parent::__construct( $params );
 		$params = $this->applyDefaultParams( $params );
 
 		$this->client = new MemCachedClientforWiki( $params );
@@ -67,23 +68,6 @@ class MemcachedPhpBagOStuff extends MemcachedBagOStuff {
 
 	/**
 	 * @param string $key
-	 * @param int $timeout
-	 * @return bool
-	 */
-	public function lock( $key, $timeout = 0 ) {
-		return $this->client->lock( $this->encodeKey( $key ), $timeout );
-	}
-
-	/**
-	 * @param string $key
-	 * @return mixed
-	 */
-	public function unlock( $key ) {
-		return $this->client->unlock( $this->encodeKey( $key ) );
-	}
-
-	/**
-	 * @param string $key
 	 * @param int $value
 	 * @return mixed
 	 */
diff --git a/includes/objectcache/MultiWriteBagOStuff.php b/includes/objectcache/MultiWriteBagOStuff.php
index 6a691379..be54e4d3 100644
--- a/includes/objectcache/MultiWriteBagOStuff.php
+++ b/includes/objectcache/MultiWriteBagOStuff.php
@@ -40,11 +40,12 @@ class MultiWriteBagOStuff extends BagOStuff {
 	 *               the documentation of $wgObjectCaches for more detail.
 	 *
 	 * @param array $params
-	 * @throws MWException
+	 * @throws InvalidArgumentException
 	 */
 	public function __construct( $params ) {
+		parent::__construct( $params );
 		if ( !isset( $params['caches'] ) ) {
-			throw new MWException( __METHOD__ . ': the caches parameter is required' );
+			throw new InvalidArgumentException( __METHOD__ . ': the caches parameter is required' );
 		}
 
 		$this->caches = array();
@@ -76,17 +77,6 @@ class MultiWriteBagOStuff extends BagOStuff {
 	}
 
 	/**
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param mixed $exptime
-	 * @return bool
-	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
-		throw new MWException( "CAS is not implemented in " . __CLASS__ );
-	}
-
-	/**
 	 * @param string $key
 	 * @param mixed $value
 	 * @param int $exptime
@@ -98,11 +88,10 @@ class MultiWriteBagOStuff extends BagOStuff {
 
 	/**
 	 * @param string $key
-	 * @param int $time
 	 * @return bool
 	 */
-	public function delete( $key, $time = 0 ) {
-		return $this->doWrite( 'delete', $key, $time );
+	public function delete( $key ) {
+		return $this->doWrite( 'delete', $key );
 	}
 
 	/**
@@ -136,12 +125,13 @@ class MultiWriteBagOStuff extends BagOStuff {
 	/**
 	 * @param string $key
 	 * @param int $timeout
+	 * @param int $expiry
 	 * @return bool
 	 */
-	public function lock( $key, $timeout = 0 ) {
+	public function lock( $key, $timeout = 6, $expiry = 6 ) {
 		// Lock only the first cache, to avoid deadlocks
 		if ( isset( $this->caches[0] ) ) {
-			return $this->caches[0]->lock( $key, $timeout );
+			return $this->caches[0]->lock( $key, $timeout, $expiry );
 		} else {
 			return true;
 		}
@@ -161,12 +151,12 @@ class MultiWriteBagOStuff extends BagOStuff {
 
 	/**
 	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
+	 * @param callable $callback Callback method to be executed
 	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
 	 * @param int $attempts The amount of times to attempt a merge in case of failure
 	 * @return bool Success
 	 */
-	public function merge( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
+	public function merge( $key, $callback, $exptime = 0, $attempts = 10 ) {
 		return $this->doWrite( 'merge', $key, $callback, $exptime );
 	}
 
diff --git a/includes/objectcache/ObjectCache.php b/includes/objectcache/ObjectCache.php
index 633b34a2..2e47e24a 100644
--- a/includes/objectcache/ObjectCache.php
+++ b/includes/objectcache/ObjectCache.php
@@ -21,6 +21,8 @@
  * @ingroup Cache
  */
 
+use MediaWiki\Logger\LoggerFactory;
+
 /**
  * Functions to get cache objects
  *
@@ -81,6 +83,13 @@ class ObjectCache {
 	 * @return BagOStuff
 	 */
 	static function newFromParams( $params ) {
+		if ( isset( $params['loggroup'] ) ) {
+			$params['logger'] = LoggerFactory::getInstance( $params['loggroup'] );
+		} else {
+			// For backwards-compatability with custom parameters, lets not
+			// have all logging suddenly disappear
+			$params['logger'] = LoggerFactory::getInstance( 'objectcache' );
+		}
 		if ( isset( $params['factory'] ) ) {
 			return call_user_func( $params['factory'], $params );
 		} elseif ( isset( $params['class'] ) ) {
@@ -135,7 +144,7 @@ class ObjectCache {
 		} elseif ( function_exists( 'wincache_ucache_get' ) ) {
 			$id = 'wincache';
 		} else {
-			if ( $fallback ) {
+			if ( $fallback !== null ) {
 				return self::newFromId( $fallback );
 			}
 			throw new MWException( "CACHE_ACCEL requested but no suitable object " .
diff --git a/includes/objectcache/ObjectCacheSessionHandler.php b/includes/objectcache/ObjectCacheSessionHandler.php
index cdf8da1e..789f1e3b 100644
--- a/includes/objectcache/ObjectCacheSessionHandler.php
+++ b/includes/objectcache/ObjectCacheSessionHandler.php
@@ -28,6 +28,9 @@
  * @ingroup Cache
  */
 class ObjectCacheSessionHandler {
+	/** @var array Map of (session ID => SHA-1 of the data) */
+	protected static $hashCache = array();
+
 	/**
 	 * Install a session handler for the current web request
 	 */
@@ -49,10 +52,11 @@ class ObjectCacheSessionHandler {
 
 	/**
 	 * Get the cache storage object to use for session storage
-	 * @return ObjectCache
+	 * @return BagOStuff
 	 */
-	static function getCache() {
+	protected static function getCache() {
 		global $wgSessionCacheType;
+
 		return ObjectCache::getInstance( $wgSessionCacheType );
 	}
 
@@ -62,11 +66,19 @@ class ObjectCacheSessionHandler {
 	 * @param string $id Session id
 	 * @return string Cache key
 	 */
-	static function getKey( $id ) {
+	protected static function getKey( $id ) {
 		return wfMemcKey( 'session', $id );
 	}
 
 	/**
+	 * @param mixed $data
+	 * @return string
+	 */
+	protected static function getHash( $data ) {
+		return sha1( serialize( $data ) );
+	}
+
+	/**
 	 * Callback when opening a session.
 	 *
 	 * @param string $save_path Path used to store session files, unused
@@ -95,22 +107,29 @@ class ObjectCacheSessionHandler {
 	 */
 	static function read( $id ) {
 		$data = self::getCache()->get( self::getKey( $id ) );
-		if ( $data === false ) {
-			return '';
-		}
-		return $data;
+
+		self::$hashCache = array( $id => self::getHash( $data ) );
+
+		return ( $data === false ) ? '' : $data;
 	}
 
 	/**
 	 * Callback when writing session data.
 	 *
 	 * @param string $id Session id
-	 * @param mixed $data Session data
+	 * @param string $data Session data
 	 * @return bool Success
 	 */
 	static function write( $id, $data ) {
 		global $wgObjectCacheSessionExpiry;
-		self::getCache()->set( self::getKey( $id ), $data, $wgObjectCacheSessionExpiry );
+
+		// Only issue a write if anything changed (PHP 5.6 already does this)
+		if ( !isset( self::$hashCache[$id] )
+			|| self::getHash( $data ) !== self::$hashCache[$id]
+		) {
+			self::getCache()->set( self::getKey( $id ), $data, $wgObjectCacheSessionExpiry );
+		}
+
 		return true;
 	}
 
@@ -122,6 +141,7 @@ class ObjectCacheSessionHandler {
 	 */
 	static function destroy( $id ) {
 		self::getCache()->delete( self::getKey( $id ) );
+
 		return true;
 	}
 
diff --git a/includes/objectcache/RedisBagOStuff.php b/includes/objectcache/RedisBagOStuff.php
index ae8cc5b7..de3511df 100644
--- a/includes/objectcache/RedisBagOStuff.php
+++ b/includes/objectcache/RedisBagOStuff.php
@@ -56,6 +56,7 @@ class RedisBagOStuff extends BagOStuff {
 	 * @param array $params
 	 */
 	function __construct( $params ) {
+		parent::__construct( $params );
 		$redisConf = array( 'serializer' => 'none' ); // manage that in this class
 		foreach ( array( 'connectTimeout', 'persistent', 'password' ) as $opt ) {
 			if ( isset( $params[$opt] ) ) {
@@ -73,7 +74,6 @@ class RedisBagOStuff extends BagOStuff {
 	}
 
 	public function get( $key, &$casToken = null ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -93,7 +93,6 @@ class RedisBagOStuff extends BagOStuff {
 	}
 
 	public function set( $key, $value, $expiry = 0 ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -116,8 +115,7 @@ class RedisBagOStuff extends BagOStuff {
 		return $result;
 	}
 
-	public function cas( $casToken, $key, $value, $expiry = 0 ) {
-		$section = new ProfileSection( __METHOD__ );
+	protected function cas( $casToken, $key, $value, $expiry = 0 ) {
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -150,8 +148,7 @@ class RedisBagOStuff extends BagOStuff {
 		return $result;
 	}
 
-	public function delete( $key, $time = 0 ) {
-		$section = new ProfileSection( __METHOD__ );
+	public function delete( $key ) {
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -171,7 +168,6 @@ class RedisBagOStuff extends BagOStuff {
 	}
 
 	public function getMulti( array $keys ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		$batches = array();
 		$conns = array();
@@ -217,7 +213,6 @@ class RedisBagOStuff extends BagOStuff {
 	 * @return bool
 	 */
 	public function setMulti( array $data, $expiry = 0 ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		$batches = array();
 		$conns = array();
@@ -265,7 +260,6 @@ class RedisBagOStuff extends BagOStuff {
 
 
 	public function add( $key, $value, $expiry = 0 ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -303,7 +297,6 @@ class RedisBagOStuff extends BagOStuff {
 	 * @return int|bool New value or false on failure
 	 */
 	public function incr( $key, $value = 1 ) {
-		$section = new ProfileSection( __METHOD__ );
 
 		list( $server, $conn ) = $this->getConnection( $key );
 		if ( !$conn ) {
@@ -322,6 +315,15 @@ class RedisBagOStuff extends BagOStuff {
 		$this->logRequest( 'incr', $key, $server, $result );
 		return $result;
 	}
+
+	public function merge( $key, $callback, $exptime = 0, $attempts = 10 ) {
+		if ( !is_callable( $callback ) ) {
+			throw new Exception( "Got invalid callback." );
+		}
+
+		return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
+	}
+
 	/**
 	 * @param mixed $data
 	 * @return string
@@ -371,7 +373,7 @@ class RedisBagOStuff extends BagOStuff {
 	 * @param string $msg
 	 */
 	protected function logError( $msg ) {
-		wfDebugLog( 'redis', "Redis error: $msg" );
+		$this->logger->error( "Redis error: $msg" );
 	}
 
 	/**
diff --git a/includes/objectcache/SqlBagOStuff.php b/includes/objectcache/SqlBagOStuff.php
index 58720790..82eeb842 100644
--- a/includes/objectcache/SqlBagOStuff.php
+++ b/includes/objectcache/SqlBagOStuff.php
@@ -88,6 +88,7 @@ class SqlBagOStuff extends BagOStuff {
 	 * @param array $params
 	 */
 	public function __construct( $params ) {
+		parent::__construct( $params );
 		if ( isset( $params['servers'] ) ) {
 			$this->serverInfos = $params['servers'];
 			$this->numServers = count( $this->serverInfos );
@@ -118,6 +119,7 @@ class SqlBagOStuff extends BagOStuff {
 	 *
 	 * @param int $serverIndex
 	 * @return DatabaseBase
+	 * @throws MWException
 	 */
 	protected function getDB( $serverIndex ) {
 		global $wgDebugDBTransactions;
@@ -137,12 +139,14 @@ class SqlBagOStuff extends BagOStuff {
 			# If server connection info was given, use that
 			if ( $this->serverInfos ) {
 				if ( $wgDebugDBTransactions ) {
-					wfDebug( "Using provided serverInfo for SqlBagOStuff\n" );
+					$this->logger->debug( "Using provided serverInfo for SqlBagOStuff" );
 				}
 				$info = $this->serverInfos[$serverIndex];
 				$type = isset( $info['type'] ) ? $info['type'] : 'mysql';
 				$host = isset( $info['host'] ) ? $info['host'] : '[unknown]';
-				wfDebug( __CLASS__ . ": connecting to $host\n" );
+				$this->logger->debug( __CLASS__ . ": connecting to $host" );
+				// Use a blank trx profiler to ignore expections as this is a cache
+				$info['trxProfiler'] = new TransactionProfiler();
 				$db = DatabaseBase::factory( $type, $info );
 				$db->clearFlag( DBO_TRX );
 			} else {
@@ -160,7 +164,7 @@ class SqlBagOStuff extends BagOStuff {
 				}
 			}
 			if ( $wgDebugDBTransactions ) {
-				wfDebug( sprintf( "Connection %s will be used for SqlBagOStuff\n", $db ) );
+				$this->logger->debug( sprintf( "Connection %s will be used for SqlBagOStuff", $db ) );
 			}
 			$this->conns[$serverIndex] = $db;
 		}
@@ -322,9 +326,7 @@ class SqlBagOStuff extends BagOStuff {
 			if ( $exptime == 0 ) {
 				$encExpiry = $this->getMaxDateTime( $db );
 			} else {
-				if ( $exptime < 3.16e8 ) { # ~10 years
-					$exptime += time();
-				}
+				$exptime = $this->convertExpiry( $exptime );
 				$encExpiry = $db->timestamp( $exptime );
 			}
 			foreach ( $serverKeys as $tableName => $tableKeys ) {
@@ -377,10 +379,7 @@ class SqlBagOStuff extends BagOStuff {
 			if ( $exptime == 0 ) {
 				$encExpiry = $this->getMaxDateTime( $db );
 			} else {
-				if ( $exptime < 3.16e8 ) { # ~10 years
-					$exptime += time();
-				}
-
+				$exptime = $this->convertExpiry( $exptime );
 				$encExpiry = $db->timestamp( $exptime );
 			}
 			// (bug 24425) use a replace if the db supports it instead of
@@ -408,7 +407,7 @@ class SqlBagOStuff extends BagOStuff {
 	 * @param int $exptime
 	 * @return bool
 	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
+	protected function cas( $casToken, $key, $value, $exptime = 0 ) {
 		list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
 		try {
 			$db = $this->getDB( $serverIndex );
@@ -421,9 +420,7 @@ class SqlBagOStuff extends BagOStuff {
 			if ( $exptime == 0 ) {
 				$encExpiry = $this->getMaxDateTime( $db );
 			} else {
-				if ( $exptime < 3.16e8 ) { # ~10 years
-					$exptime += time();
-				}
+				$exptime = $this->convertExpiry( $exptime );
 				$encExpiry = $db->timestamp( $exptime );
 			}
 			// (bug 24425) use a replace if the db supports it instead of
@@ -452,10 +449,9 @@ class SqlBagOStuff extends BagOStuff {
 
 	/**
 	 * @param string $key
-	 * @param int $time
 	 * @return bool
 	 */
-	public function delete( $key, $time = 0 ) {
+	public function delete( $key ) {
 		list( $serverIndex, $tableName ) = $this->getTableByKey( $key );
 		try {
 			$db = $this->getDB( $serverIndex );
@@ -520,6 +516,14 @@ class SqlBagOStuff extends BagOStuff {
 		return $newValue;
 	}
 
+	public function merge( $key, $callback, $exptime = 0, $attempts = 10 ) {
+		if ( !is_callable( $callback ) ) {
+			throw new Exception( "Got invalid callback." );
+		}
+
+		return $this->mergeViaCas( $key, $callback, $exptime, $attempts );
+	}
+
 	/**
 	 * @param DatabaseBase $db
 	 * @param string $exptime
@@ -621,7 +625,8 @@ class SqlBagOStuff extends BagOStuff {
 								if ( $remainingSeconds > $totalSeconds ) {
 									$totalSeconds = $remainingSeconds;
 								}
-								$percent = ( $i + $remainingSeconds / $totalSeconds )
+								$processedSeconds = $totalSeconds - $remainingSeconds;
+								$percent = ( $i + $processedSeconds / $totalSeconds )
 									/ $this->shards * 100;
 							}
 							$percent = ( $percent / $this->numServers )
@@ -638,6 +643,11 @@ class SqlBagOStuff extends BagOStuff {
 		return true;
 	}
 
+	/**
+	 * Delete content of shard tables in every server.
+	 * Return true if the operation is successful, false otherwise.
+	 * @return bool
+	 */
 	public function deleteAll() {
 		for ( $serverIndex = 0; $serverIndex < $this->numServers; $serverIndex++ ) {
 			try {
@@ -702,13 +712,13 @@ class SqlBagOStuff extends BagOStuff {
 		if ( $exception instanceof DBConnectionError ) {
 			$this->markServerDown( $exception, $serverIndex );
 		}
-		wfDebugLog( 'SQLBagOStuff', "DBError: {$exception->getMessage()}" );
+		$this->logger->error( "DBError: {$exception->getMessage()}" );
 		if ( $exception instanceof DBConnectionError ) {
 			$this->setLastError( BagOStuff::ERR_UNREACHABLE );
-			wfDebug( __METHOD__ . ": ignoring connection error\n" );
+			$this->logger->debug( __METHOD__ . ": ignoring connection error" );
 		} else {
 			$this->setLastError( BagOStuff::ERR_UNEXPECTED );
-			wfDebug( __METHOD__ . ": ignoring query error\n" );
+			$this->logger->debug( __METHOD__ . ": ignoring query error" );
 		}
 	}
 
@@ -723,18 +733,21 @@ class SqlBagOStuff extends BagOStuff {
 			$this->markServerDown( $exception, $serverIndex );
 		}
 		if ( $exception->db && $exception->db->wasReadOnlyError() ) {
-			try {
-				$exception->db->rollback( __METHOD__ );
-			} catch ( DBError $e ) {
+			if ( $exception->db->trxLevel() ) {
+				try {
+					$exception->db->rollback( __METHOD__ );
+				} catch ( DBError $e ) {
+				}
 			}
 		}
-		wfDebugLog( 'SQLBagOStuff', "DBError: {$exception->getMessage()}" );
+
+		$this->logger->error( "DBError: {$exception->getMessage()}" );
 		if ( $exception instanceof DBConnectionError ) {
 			$this->setLastError( BagOStuff::ERR_UNREACHABLE );
-			wfDebug( __METHOD__ . ": ignoring connection error\n" );
+			$this->logger->debug( __METHOD__ . ": ignoring connection error" );
 		} else {
 			$this->setLastError( BagOStuff::ERR_UNEXPECTED );
-			wfDebug( __METHOD__ . ": ignoring query error\n" );
+			$this->logger->debug( __METHOD__ . ": ignoring query error" );
 		}
 	}
 
@@ -750,12 +763,12 @@ class SqlBagOStuff extends BagOStuff {
 				unset( $this->connFailureTimes[$serverIndex] );
 				unset( $this->connFailureErrors[$serverIndex] );
 			} else {
-				wfDebug( __METHOD__ . ": Server #$serverIndex already down\n" );
+				$this->logger->debug( __METHOD__ . ": Server #$serverIndex already down" );
 				return;
 			}
 		}
 		$now = time();
-		wfDebug( __METHOD__ . ": Server #$serverIndex down until " . ( $now + 60 ) . "\n" );
+		$this->logger->info( __METHOD__ . ": Server #$serverIndex down until " . ( $now + 60 ) );
 		$this->connFailureTimes[$serverIndex] = $now;
 		$this->connFailureErrors[$serverIndex] = $exception;
 	}
@@ -779,9 +792,3 @@ class SqlBagOStuff extends BagOStuff {
 		}
 	}
 }
-
-/**
- * Backwards compatibility alias
- */
-class MediaWikiBagOStuff extends SqlBagOStuff {
-}
diff --git a/includes/objectcache/WinCacheBagOStuff.php b/includes/objectcache/WinCacheBagOStuff.php
deleted file mode 100644
index 78a512ce..00000000
--- a/includes/objectcache/WinCacheBagOStuff.php
+++ /dev/null
@@ -1,92 +0,0 @@
-<?php
-/**
- * Object caching using WinCache.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * Wrapper for WinCache object caching functions; identical interface
- * to the APC wrapper
- *
- * @ingroup Cache
- */
-class WinCacheBagOStuff extends BagOStuff {
-
-	/**
-	 * Get a value from the WinCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param int $casToken [optional] Cas token
-	 * @return mixed
-	 */
-	public function get( $key, &$casToken = null ) {
-		$val = wincache_ucache_get( $key );
-
-		$casToken = $val;
-
-		if ( is_string( $val ) ) {
-			$val = unserialize( $val );
-		}
-
-		return $val;
-	}
-
-	/**
-	 * Store a value in the WinCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param mixed $value Value to store
-	 * @param int $expire Expiration time
-	 * @return bool
-	 */
-	public function set( $key, $value, $expire = 0 ) {
-		$result = wincache_ucache_set( $key, serialize( $value ), $expire );
-
-		/* wincache_ucache_set returns an empty array on success if $value
-		   was an array, bool otherwise */
-		return ( is_array( $result ) && $result === array() ) || $result;
-	}
-
-	/**
-	 * Store a value in the WinCache object cache, race condition-safe
-	 *
-	 * @param int $casToken Cas token
-	 * @param string $key Cache key
-	 * @param int $value Object to store
-	 * @param int $exptime Expiration time
-	 * @return bool
-	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
-		return wincache_ucache_cas( $key, $casToken, serialize( $value ) );
-	}
-
-	/**
-	 * Remove a value from the WinCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param int $time Not used in this implementation
-	 * @return bool
-	 */
-	public function delete( $key, $time = 0 ) {
-		wincache_ucache_delete( $key );
-
-		return true;
-	}
-}
diff --git a/includes/objectcache/XCacheBagOStuff.php b/includes/objectcache/XCacheBagOStuff.php
deleted file mode 100644
index 8e2a160d..00000000
--- a/includes/objectcache/XCacheBagOStuff.php
+++ /dev/null
@@ -1,117 +0,0 @@
-<?php
-/**
- * Object caching using XCache.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Cache
- */
-
-/**
- * Wrapper for XCache object caching functions; identical interface
- * to the APC wrapper
- *
- * @ingroup Cache
- */
-class XCacheBagOStuff extends BagOStuff {
-	/**
-	 * Get a value from the XCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param mixed $casToken Cas token
-	 * @return mixed
-	 */
-	public function get( $key, &$casToken = null ) {
-		$val = xcache_get( $key );
-
-		if ( is_string( $val ) ) {
-			if ( $this->isInteger( $val ) ) {
-				$val = intval( $val );
-			} else {
-				$val = unserialize( $val );
-			}
-		} elseif ( is_null( $val ) ) {
-			return false;
-		}
-
-		return $val;
-	}
-
-	/**
-	 * Store a value in the XCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param mixed $value Object to store
-	 * @param int $expire Expiration time
-	 * @return bool
-	 */
-	public function set( $key, $value, $expire = 0 ) {
-		if ( !$this->isInteger( $value ) ) {
-			$value = serialize( $value );
-		}
-
-		xcache_set( $key, $value, $expire );
-		return true;
-	}
-
-	/**
-	 * @param mixed $casToken
-	 * @param string $key
-	 * @param mixed $value
-	 * @param int $exptime
-	 * @return bool
-	 */
-	public function cas( $casToken, $key, $value, $exptime = 0 ) {
-		// Can't find any documentation on xcache cas
-		throw new MWException( "CAS is not implemented in " . __CLASS__ );
-	}
-
-	/**
-	 * Remove a value from the XCache object cache
-	 *
-	 * @param string $key Cache key
-	 * @param int $time Not used in this implementation
-	 * @return bool
-	 */
-	public function delete( $key, $time = 0 ) {
-		xcache_unset( $key );
-		return true;
-	}
-
-	/**
-	 * Merge an item.
-	 * XCache does not seem to support any way of performing CAS - this however will
-	 * provide a way to perform CAS-like functionality.
-	 *
-	 * @param string $key
-	 * @param Closure $callback Callback method to be executed
-	 * @param int $exptime Either an interval in seconds or a unix timestamp for expiry
-	 * @param int $attempts The amount of times to attempt a merge in case of failure
-	 * @return bool Success
-	 */
-	public function merge( $key, Closure $callback, $exptime = 0, $attempts = 10 ) {
-		return $this->mergeViaLock( $key, $callback, $exptime, $attempts );
-	}
-
-	public function incr( $key, $value = 1 ) {
-		return xcache_inc( $key, $value );
-	}
-
-	public function decr( $key, $value = 1 ) {
-		return xcache_dec( $key, $value );
-	}
-}