Merge "Lower CDN cache TTL when slave lag is high"

diff --combined includes/db/loadbalancer/LoadBalancer.php
index cd3b006,95e71c7..3350d19
--- 1/includes/db/loadbalancer/LoadBalancer.php
--- 2/includes/db/loadbalancer/LoadBalancer.php
+++ b/includes/db/loadbalancer/LoadBalancer.php
@@@ -546,14 -546,6 +546,14 @@@ class LoadBalancer 
                        $trxProf->recordConnection( $host, $dbname, $masterOnly );
                }
  
 +              # Make master connections read only if in lagged slave mode
 +              if ( $masterOnly && $this->getServerCount() > 1 && $this->getLaggedSlaveMode() ) {
 +                      $conn->setLBInfo( 'readOnlyReason',
 +                              'The database has been automatically locked ' .
 +                              'while the slave database servers catch up to the master'
 +                      );
 +              }
 +
                return $conn;
        }
  
@@@ -1139,6 -1131,7 +1139,7 @@@
        }
  
        /**
+        * @note This method will trigger a DB connection if not yet done
         * @return bool Whether the generic connection for reads is highly "lagged"
         */
        public function getLaggedSlaveMode() {
@@@ -1148,6 -1141,15 +1149,15 @@@
                return $this->mLaggedSlaveMode;
        }
  
+       /**
+        * @note This method will never cause a new DB connection
+        * @return bool Whether any generic connection used for reads was highly "lagged"
+        * @since 1.27
+        */
+       public function laggedSlaveUsed() {
+               return $this->mLaggedSlaveMode;
+       }
+ 
        /**
         * Disables/enables lag checks
         * @param null|bool $mode