Merge "Drop index oi_name_archive_name on table oldimage"

[lhc/web/wiklou.git] / includes / libs / rdbms / loadmonitor / LoadMonitor.php

diff --git a/includes/libs/rdbms/loadmonitor/LoadMonitor.php b/includes/libs/rdbms/loadmonitor/LoadMonitor.php
index 60400e3..5e92c33 100644 (file)
--- a/includes/libs/rdbms/loadmonitor/LoadMonitor.php
+++ b/includes/libs/rdbms/loadmonitor/LoadMonitor.php
@@ -19,7 +19,13 @@
  * @ingroup Database
  */
 
+namespace Wikimedia\Rdbms;
+
 use Psr\Log\LoggerInterface;
+use Psr\Log\NullLogger;
+use Wikimedia\ScopedCallback;
+use IDatabase;
+use BagOStuff;
 
 /**
  * Basic DB load monitor with no external dependencies
@@ -40,7 +46,7 @@ class LoadMonitor implements ILoadMonitor {
        /** @var float Moving average ratio (e.g. 0.1 for 10% weight to new weight) */
        private $movingAveRatio;
 
-       const VERSION = 1;
+       const VERSION = 1; // cache key version
 
        public function __construct(
                ILoadBalancer $lb, BagOStuff $srvCache, BagOStuff $cache, array $options = []
@@ -48,7 +54,7 @@ class LoadMonitor implements ILoadMonitor {
                $this->parent = $lb;
                $this->srvCache = $srvCache;
                $this->mainCache = $cache;
-               $this->replLogger = new \Psr\Log\NullLogger();
+               $this->replLogger = new NullLogger();
 
                $this->movingAveRatio = isset( $options['movingAveRatio'] )
                        ? $options['movingAveRatio']
@@ -59,12 +65,17 @@ class LoadMonitor implements ILoadMonitor {
                $this->replLogger = $logger;
        }
 
-       public function scaleLoads( array &$weightByServer, $group = false, $domain = false ) {
+       public function scaleLoads( array &$weightByServer, $domain ) {
                $serverIndexes = array_keys( $weightByServer );
                $states = $this->getServerStates( $serverIndexes, $domain );
                $coefficientsByServer = $states['weightScales'];
                foreach ( $weightByServer as $i => $weight ) {
-                       $weightByServer[$i] = $weight * $coefficientsByServer[$i];
+                       if ( isset( $coefficientsByServer[$i] ) ) {
+                               $weightByServer[$i] = $weight * $coefficientsByServer[$i];
+                       } else { // server recently added to config?
+                               $host = $this->parent->getServerName( $i );
+                               $this->replLogger->error( __METHOD__ . ": host $host not in cache" );
+                       }
                }
        }
 
@@ -75,15 +86,16 @@ class LoadMonitor implements ILoadMonitor {
        }
 
        protected function getServerStates( array $serverIndexes, $domain ) {
-               if ( count( $serverIndexes ) == 1 && reset( $serverIndexes ) == 0 ) {
+               $writerIndex = $this->parent->getWriterIndex();
+               if ( count( $serverIndexes ) == 1 && reset( $serverIndexes ) == $writerIndex ) {
                        # Single server only, just return zero without caching
                        return [
-                               'lagTimes' => [ $this->parent->getWriterIndex() => 0 ],
-                               'weightScales' => [ $this->parent->getWriterIndex() => 1 ]
+                               'lagTimes' => [ $writerIndex => 0 ],
+                               'weightScales' => [ $writerIndex => 1.0 ]
                        ];
                }
 
-               $key = $this->getCacheKey();
+               $key = $this->getCacheKey( $serverIndexes );
                # Randomize TTLs to reduce stampedes (4.0 - 5.0 sec)
                $ttl = mt_rand( 4e6, 5e6 ) / 1e6;
                # Keep keys around longer as fallbacks
@@ -154,10 +166,14 @@ class LoadMonitor implements ILoadMonitor {
                                continue;
                        }
 
-                       $lagTimes[$i] = $conn->getLag();
-                       if ( $lagTimes[$i] === false ) {
-                               $host = $this->parent->getServerName( $i );
-                               $this->replLogger->error( __METHOD__ . ": host $host is not replicating?" );
+                       if ( $conn->getLBInfo( 'is static' ) ) {
+                               $lagTimes[$i] = 0;
+                       } else {
+                               $lagTimes[$i] = $conn->getLag();
+                               if ( $lagTimes[$i] === false ) {
+                                       $host = $this->parent->getServerName( $i );
+                                       $this->replLogger->error( __METHOD__ . ": host $host is not replicating?" );
+                               }
                        }
 
                        if ( $close ) {
@@ -191,18 +207,14 @@ class LoadMonitor implements ILoadMonitor {
                return $conn ? 1.0 : 0.0;
        }
 
-       public function clearCaches() {
-               $key = $this->getCacheKey();
-               $this->srvCache->delete( $key );
-               $this->mainCache->delete( $key );
-       }
-
-       private function getCacheKey() {
+       private function getCacheKey( array $serverIndexes ) {
+               sort( $serverIndexes );
                // Lag is per-server, not per-DB, so key on the master DB name
                return $this->srvCache->makeGlobalKey(
                        'lag-times',
                        self::VERSION,
-                       $this->parent->getServerName( $this->parent->getWriterIndex() )
+                       $this->parent->getServerName( $this->parent->getWriterIndex() ),
+                       implode( '-', $serverIndexes )
                );
        }
 }