Various database class cleanups

[lhc/web/wiklou.git] / includes / db / loadbalancer / LoadBalancer.php

diff --git a/includes/db/loadbalancer/LoadBalancer.php b/includes/db/loadbalancer/LoadBalancer.php
index f045acf..13a0879 100644 (file)
--- a/includes/db/loadbalancer/LoadBalancer.php
+++ b/includes/db/loadbalancer/LoadBalancer.php
@@ -1090,7 +1090,7 @@ class LoadBalancer {
        public function approveMasterChanges( array $options ) {
                $limit = isset( $options['maxWriteDuration'] ) ? $options['maxWriteDuration'] : 0;
                $this->forEachOpenMasterConnection( function ( DatabaseBase $conn ) use ( $limit ) {
-                       // If atomic section or explicit transactions are still open, some caller must have
+                       // If atomic sections or explicit transactions are still open, some caller must have
                        // caught an exception but failed to properly rollback any changes. Detect that and
                        // throw and error (causing rollback).
                        if ( $conn->explicitTrxActive() ) {
@@ -1108,6 +1108,14 @@ class LoadBalancer {
                                        wfMessage( 'transaction-duration-limit-exceeded', $time, $limit )->text()
                                );
                        }
+                       // If a connection sits idle while slow queries execute on another, that connection
+                       // may end up dropped before the commit round is reached. Ping servers to detect this.
+                       if ( $conn->writesOrCallbacksPending() && !$conn->ping() ) {
+                               throw new DBTransactionError(
+                                       $conn,
+                                       "A connection to the {$conn->getDBname()} database was lost before commit."
+                               );
+                       }
                } );
        }