various load balancing tweaks

diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index 4911d3e..6b9751d 100644 (file)
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -416,6 +416,9 @@ $wgMasterWaitTimeout = 10;
 /** File to log MySQL errors to */
 $wgDBerrorLog          = false;
 
+/** When to give an error message */
+$wgDBClusterTimeout = 10;
+
 /**
  * wgDBminWordLen :
  * MySQL 3.x : used to discard words that MySQL will not return any results for

diff --git a/includes/LoadBalancer.php b/includes/LoadBalancer.php
index 5ed207c..a60d284 100644 (file)
--- a/includes/LoadBalancer.php
+++ b/includes/LoadBalancer.php
@@ -148,7 +148,7 @@ class LoadBalancer {
 
        function getReaderIndex()
        {
-               global $wgMaxLag, $wgReadOnly;
+               global $wgMaxLag, $wgReadOnly, $wgDBClusterTimeout;
 
                $fname = 'LoadBalancer::getReaderIndex';
                wfProfileIn( $fname );
@@ -206,10 +206,18 @@ class LoadBalancer {
                                                        $totalElapsed += $sleepTime;
                                                        usleep( $sleepTime );
                                        }
-                               } while ( count( $loads ) && !$done && $totalElapsed / 1e6 < $this->mWaitTimeout );
+                               } while ( count( $loads ) && !$done && $totalElapsed / 1e6 < $wgDBClusterTimeout );
 
                                if ( $i !== false && $this->isOpen( $i ) ) {
-                                       $this->mReadIndex = $i;
+                                       # Wait for the session master pos for a short time
+                                       if ( $this->mWaitForFile ) {
+                                               if ( !$this->doWait( $i ) ) {
+                                                       $this->mServers[$i]['slave pos'] = $this->mConnections[$i]->getSlavePos();
+                                               }
+                                       }
+                                       if ( $i != false ) {
+                                               $this->mReadIndex = $i;
+                                       }
                                } else {
                                        $i = false;
                                }
@@ -238,7 +246,6 @@ class LoadBalancer {
         * Otherwise sets a variable telling it to wait if such a connection is opened
         */
        function waitFor( $file, $pos ) {
-               /*
                $fname = 'LoadBalancer::waitFor';
                wfProfileIn( $fname );
 
@@ -259,15 +266,12 @@ class LoadBalancer {
                        } 
                }
                wfProfileOut( $fname );
-               */
        }
 
        /**
         * Wait for a given slave to catch up to the master pos stored in $this
         */
        function doWait( $index ) {
-               return true;
-               /*
                global $wgMemc;
                
                $retVal = false;
@@ -303,7 +307,7 @@ class LoadBalancer {
                                wfDebug( "Done\n" );
                        }
                }
-               return $retVal;*/
+               return $retVal;
        }               
 
        /**
@@ -358,13 +362,6 @@ class LoadBalancer {
 
                if ( !$this->isOpen( $i ) ) {
                        $this->mConnections[$i] = $this->reallyOpenConnection( $this->mServers[$i] );
-
-                       if ( $this->isOpen( $i ) && $i != 0 && $this->mWaitForFile ) {
-                               if ( !$this->doWait( $i ) ) {
-                                       $this->mServers[$i]['slave pos'] = $this->mConnections[$i]->getSlavePos();
-                                       $success = false;
-                               }
-                       }
                }
                if ( !$this->isOpen( $i ) ) {
                        wfDebug( "Failed to connect to database $i at {$this->mServers[$i]['host']}\n" );