Rename some DB/LB variables to be more consistent

Change-Id: I21de9c972402144159b7b2fc824533f8cefb03e7

diff --git a/includes/db/Database.php b/includes/db/Database.php
index 5b0f230..786d5f9 100644 (file)
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -128,7 +128,7 @@ abstract class DatabaseBase implements IDatabase {
         */
        private $mTrxTimestamp = null;
        /** @var float Lag estimate at the time of BEGIN */
-       private $mTrxSlaveLag = null;
+       private $mTrxReplicaLag = null;
        /**
         * Remembers the function name given for starting the most recent transaction via begin().
         * Used to provide additional context for error reporting.
@@ -1028,20 +1028,21 @@ abstract class DatabaseBase implements IDatabase {
         * @param float $runtime Total runtime, including RTT
         */
        private function updateTrxWriteQueryTime( $sql, $runtime ) {
-               $indicativeOfSlaveRuntime = true;
+               // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
+               $indicativeOfReplicaRuntime = true;
                if ( $runtime > self::SLOW_WRITE_SEC ) {
                        $verb = $this->getQueryVerb( $sql );
                        // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
                        if ( $verb === 'INSERT' ) {
-                               $indicativeOfSlaveRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS;
+                               $indicativeOfReplicaRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS;
                        } elseif ( $verb === 'REPLACE' ) {
-                               $indicativeOfSlaveRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS / 2;
+                               $indicativeOfReplicaRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS / 2;
                        }
                }
 
                $this->mTrxWriteDuration += $runtime;
                $this->mTrxWriteQueryCount += 1;
-               if ( $indicativeOfSlaveRuntime ) {
+               if ( $indicativeOfReplicaRuntime ) {
                        $this->mTrxWriteAdjDuration += $runtime;
                        $this->mTrxWriteAdjQueryCount += 1;
                }
@@ -2911,7 +2912,7 @@ abstract class DatabaseBase implements IDatabase {
                // Get an estimate of the replica DB lag before then, treating estimate staleness
                // as lag itself just to be safe
                $status = $this->getApproximateLagStatus();
-               $this->mTrxSlaveLag = $status['lag'] + ( microtime( true ) - $status['since'] );
+               $this->mTrxReplicaLag = $status['lag'] + ( microtime( true ) - $status['since'] );
        }
 
        /**
@@ -3206,7 +3207,7 @@ abstract class DatabaseBase implements IDatabase {
         */
        public function getTransactionLagStatus() {
                return $this->mTrxLevel
-                       ? [ 'lag' => $this->mTrxSlaveLag, 'since' => $this->trxTimestamp() ]
+                       ? [ 'lag' => $this->mTrxReplicaLag, 'since' => $this->trxTimestamp() ]
                        : null;
        }
 

diff --git a/includes/db/loadbalancer/LoadBalancer.php b/includes/db/loadbalancer/LoadBalancer.php
index 36df466..7ca0b33 100644 (file)
--- a/includes/db/loadbalancer/LoadBalancer.php
+++ b/includes/db/loadbalancer/LoadBalancer.php
@@ -61,9 +61,9 @@ class LoadBalancer {
        /** @var bool|DBMasterPos False if not set */
        private $mWaitForPos;
        /** @var bool Whether the generic reader fell back to a lagged replica DB */
-       private $laggedSlaveMode = false;
+       private $laggedReplicaMode = false;
        /** @var bool Whether the generic reader fell back to a lagged replica DB */
-       private $slavesDownMode = false;
+       private $allReplicasDownMode = false;
        /** @var string The last DB selection or connection error */
        private $mLastError = 'Unknown error';
        /** @var string|bool Reason the LB is read-only or false if not */
@@ -280,7 +280,7 @@ class LoadBalancer {
                # Scale the configured load ratios according to the dynamic load (if the load monitor supports it)
                $this->getLoadMonitor()->scaleLoads( $nonErrorLoads, $group, $wiki );
 
-               $laggedSlaveMode = false;
+               $laggedReplicaMode = false;
 
                # No server found yet
                $i = false;
@@ -289,7 +289,7 @@ class LoadBalancer {
                # meets our criteria
                $currentLoads = $nonErrorLoads;
                while ( count( $currentLoads ) ) {
-                       if ( $this->mAllowLagged || $laggedSlaveMode ) {
+                       if ( $this->mAllowLagged || $laggedReplicaMode ) {
                                $i = ArrayUtils::pickRandom( $currentLoads );
                        } else {
                                $i = false;
@@ -309,7 +309,7 @@ class LoadBalancer {
                                        # All replica DBs lagged. Switch to read-only mode
                                        wfDebugLog( 'replication', "All replica DBs lagged. Switch to read-only mode" );
                                        $i = ArrayUtils::pickRandom( $currentLoads );
-                                       $laggedSlaveMode = true;
+                                       $laggedReplicaMode = true;
                                }
                        }
 
@@ -350,8 +350,8 @@ class LoadBalancer {
                }
 
                if ( $i !== false ) {
-                       # replica DB connection successful
-                       # Wait for the session master pos for a short time
+                       # Replica DB connection successful.
+                       # Wait for the session master pos for a short time.
                        if ( $this->mWaitForPos && $i > 0 ) {
                                if ( !$this->doWait( $i ) ) {
                                        $this->mServers[$i]['slave pos'] = $conn->getSlavePos();
@@ -360,8 +360,8 @@ class LoadBalancer {
                        if ( $this->mReadIndex <= 0 && $this->mLoads[$i] > 0 && $group === false ) {
                                $this->mReadIndex = $i;
                                # Record if the generic reader index is in "lagged replica DB" mode
-                               if ( $laggedSlaveMode ) {
-                                       $this->laggedSlaveMode = true;
+                               if ( $laggedReplicaMode ) {
+                                       $this->laggedReplicaMode = true;
                                }
                        }
                        $serverName = $this->getServerName( $i );
@@ -385,7 +385,7 @@ class LoadBalancer {
                if ( $i > 0 ) {
                        if ( !$this->doWait( $i ) ) {
                                $this->mServers[$i]['slave pos'] = $this->getAnyOpenConnection( $i )->getSlavePos();
-                               $this->laggedSlaveMode = true;
+                               $this->laggedReplicaMode = true;
                        }
                }
        }
@@ -1431,19 +1431,19 @@ class LoadBalancer {
         */
        public function getLaggedSlaveMode( $wiki = false ) {
                // No-op if there is only one DB (also avoids recursion)
-               if ( !$this->laggedSlaveMode && $this->getServerCount() > 1 ) {
+               if ( !$this->laggedReplicaMode && $this->getServerCount() > 1 ) {
                        try {
-                               // See if laggedSlaveMode gets set
+                               // See if laggedReplicaMode gets set
                                $conn = $this->getConnection( DB_SLAVE, false, $wiki );
                                $this->reuseConnection( $conn );
                        } catch ( DBConnectionError $e ) {
                                // Avoid expensive re-connect attempts and failures
-                               $this->slavesDownMode = true;
-                               $this->laggedSlaveMode = true;
+                               $this->allReplicasDownMode = true;
+                               $this->laggedReplicaMode = true;
                        }
                }
 
-               return $this->laggedSlaveMode;
+               return $this->laggedReplicaMode;
        }
 
        /**
@@ -1452,7 +1452,7 @@ class LoadBalancer {
         * @since 1.27
         */
        public function laggedSlaveUsed() {
-               return $this->laggedSlaveMode;
+               return $this->laggedReplicaMode;
        }
 
        /**
@@ -1466,7 +1466,7 @@ class LoadBalancer {
                if ( $this->readOnlyReason !== false ) {
                        return $this->readOnlyReason;
                } elseif ( $this->getLaggedSlaveMode( $wiki ) ) {
-                       if ( $this->slavesDownMode ) {
+                       if ( $this->allReplicasDownMode ) {
                                return 'The database has been automatically locked ' .
                                        'until the replica database servers become available';
                        } else {