Merge "Make JobQueueGroup::push() update the queuesHaveJobs() cache"

[lhc/web/wiklou.git] / includes / db / ChronologyProtector.php

diff --git a/includes/db/ChronologyProtector.php b/includes/db/ChronologyProtector.php
index b4619f3..39c9957 100644 (file)
--- a/includes/db/ChronologyProtector.php
+++ b/includes/db/ChronologyProtector.php
@@ -31,8 +31,8 @@ class ChronologyProtector {
 
        /** @var string Storage key name */
        protected $key;
-       /** @var array Map of (ip: <IP>, agent: <user-agent>) */
-       protected $client;
+       /** @var string Hash of client parameters */
+       protected $clientId;
        /** @var bool Whether to no-op all method calls */
        protected $enabled = true;
        /** @var bool Whether to check and wait on positions */
@@ -44,6 +44,8 @@ class ChronologyProtector {
        protected $startupPositions = [];
        /** @var DBMasterPos[] Map of (DB master name => position) */
        protected $shutdownPositions = [];
+       /** @var float[] Map of (DB master name => 1) */
+       protected $shutdownTouchDBs = [];
 
        /**
         * @param BagOStuff $store
@@ -52,11 +54,8 @@ class ChronologyProtector {
         */
        public function __construct( BagOStuff $store, array $client ) {
                $this->store = $store;
-               $this->client = $client;
-               $this->key = $store->makeGlobalKey(
-                       'ChronologyProtector',
-                       md5( $client['ip'] . "\n" . $client['agent'] )
-               );
+               $this->clientId = md5( $client['ip'] . "\n" . $client['agent'] );
+               $this->key = $store->makeGlobalKey( __CLASS__, $this->clientId );
        }
 
        /**
@@ -95,10 +94,8 @@ class ChronologyProtector {
 
                $masterName = $lb->getServerName( $lb->getWriterIndex() );
                if ( !empty( $this->startupPositions[$masterName] ) ) {
-                       $info = $lb->parentInfo();
                        $pos = $this->startupPositions[$masterName];
-                       wfDebugLog( 'replication', __METHOD__ .
-                               ": LB '" . $info['id'] . "' waiting for master pos $pos\n" );
+                       wfDebugLog( 'replication', __METHOD__ . ": LB for '$masterName' set to pos $pos\n" );
                        $lb->waitFor( $pos );
                }
        }
@@ -111,35 +108,47 @@ class ChronologyProtector {
         * @return void
         */
        public function shutdownLB( LoadBalancer $lb ) {
-               if ( !$this->enabled || $lb->getServerCount() <= 1 ) {
-                       return; // non-replicated setup or disabled
+               if ( !$this->enabled ) {
+                       return; // not enabled
+               } elseif ( !$lb->hasOrMadeRecentMasterChanges( INF ) ) {
+                       // Only save the position if writes have been done on the connection
+                       return;
                }
 
-               $info = $lb->parentInfo();
                $masterName = $lb->getServerName( $lb->getWriterIndex() );
-
-               // Only save the position if writes have been done on the connection
-               $db = $lb->getAnyOpenConnection( $lb->getWriterIndex() );
-               if ( !$db || !$db->doneWrites() ) {
-                       wfDebugLog( 'replication', __METHOD__ . ": LB {$info['id']}, no writes done\n" );
-
-                       return; // nothing to do
+               if ( $lb->getServerCount() > 1 ) {
+                       $pos = $lb->getMasterPos();
+                       wfDebugLog( 'replication', __METHOD__ . ": LB for '$masterName' has pos $pos\n" );
+                       $this->shutdownPositions[$masterName] = $pos;
+               } else {
+                       wfDebugLog( 'replication', __METHOD__ . ": DB '$masterName' touched\n" );
                }
-
-               $pos = $db->getMasterPos();
-               wfDebugLog( 'replication', __METHOD__ . ": LB {$info['id']} has master pos $pos\n" );
-               $this->shutdownPositions[$masterName] = $pos;
+               $this->shutdownTouchDBs[$masterName] = 1;
        }
 
        /**
         * Notify the ChronologyProtector that the LBFactory is done calling shutdownLB() for now.
         * May commit chronology data to persistent storage.
         *
-        * @return array Empty on success; returns the (db name => position) map on failure
+        * @return DBMasterPos[] Empty on success; returns the (db name => position) map on failure
         */
        public function shutdown() {
-               if ( !$this->enabled || !count( $this->shutdownPositions ) ) {
-                       return true; // nothing to save
+               if ( !$this->enabled ) {
+                       return [];
+               }
+
+               // Some callers might want to know if a user recently touched a DB.
+               // These writes do not need to block on all datacenters receiving them.
+               foreach ( $this->shutdownTouchDBs as $dbName => $unused ) {
+                       $this->store->set(
+                               $this->getTouchedKey( $this->store, $dbName ),
+                               microtime( true ),
+                               BagOStuff::TTL_DAY
+                       );
+               }
+
+               if ( !count( $this->shutdownPositions ) ) {
+                       return []; // nothing to save
                }
 
                wfDebugLog( 'replication',
@@ -175,6 +184,24 @@ class ChronologyProtector {
                return [];
        }
 
+       /**
+        * @param string $dbName DB master name (e.g. "db1052")
+        * @return float|bool UNIX timestamp when client last touched the DB; false if not on record
+        * @since 1.28
+        */
+       public function getTouched( $dbName ) {
+               return $this->store->get( $this->getTouchedKey( $this->store, $dbName ) );
+       }
+
+       /**
+        * @param BagOStuff $store
+        * @param string $dbName
+        * @return string
+        */
+       private function getTouchedKey( BagOStuff $store, $dbName ) {
+               return $store->makeGlobalKey( __CLASS__, 'mtime', $this->clientId, $dbName );
+       }
+
        /**
         * Load in previous master positions for the client
         */
@@ -187,11 +214,9 @@ class ChronologyProtector {
                if ( $this->wait ) {
                        $data = $this->store->get( $this->key );
                        $this->startupPositions = $data ? $data['positions'] : [];
-
                        wfDebugLog( 'replication', __METHOD__ . ": key is {$this->key} (read)\n" );
                } else {
                        $this->startupPositions = [];
-
                        wfDebugLog( 'replication', __METHOD__ . ": key is {$this->key} (unread)\n" );
                }
        }