Applying live hacks from Wikimedia code base:

* Clarify profiling results for local and remote repo lookups
* Use master database for critical lookups
* Don't upgrade db rows when in read-only mode

diff --git a/includes/filerepo/LocalFile.php b/includes/filerepo/LocalFile.php
index d763c57..3409b5b 100644 (file)
--- a/includes/filerepo/LocalFile.php
+++ b/includes/filerepo/LocalFile.php
@@ -183,7 +183,7 @@ class LocalFile extends File
                # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
                $this->dataLoaded = true;
 
-               $dbr = $this->repo->getSlaveDB();
+               $dbr = $this->repo->getMasterDB();
 
                $row = $dbr->selectRow( 'image', $this->getCacheFields( 'img_' ),
                        array( 'img_name' => $this->getName() ), $fname );
@@ -293,6 +293,9 @@ class LocalFile extends File
                $dbw = $this->repo->getMasterDB();
                list( $major, $minor ) = self::splitMime( $this->mime );
 
+               if ( wfReadOnly() ) {
+                       return;
+               }
                wfDebug(__METHOD__.': upgrading '.$this->getName()." to the current schema\n");
 
                $dbw->update( 'image',
@@ -608,6 +611,9 @@ class LocalFile extends File
         * @public
         */
        function nextHistoryLine() {
+               # Polymorphic function name to distinguish foreign and local fetches
+               $fname = get_class( $this ) . '::' . __FUNCTION__;
+
                $dbr = $this->repo->getSlaveDB();
 
                if ( $this->historyLine == 0 ) {// called for the first time, return line from cur
@@ -617,7 +623,7 @@ class LocalFile extends File
                                        "'' AS oi_archive_name"
                                ),
                                array( 'img_name' => $this->title->getDBkey() ),
-                               __METHOD__
+                               $fname
                        );
                        if ( 0 == $dbr->numRows( $this->historyRes ) ) {
                                $dbr->freeResult($this->historyRes);
@@ -628,7 +634,7 @@ class LocalFile extends File
                        $dbr->freeResult($this->historyRes);
                        $this->historyRes = $dbr->select( 'oldimage', '*', 
                                array( 'oi_name' => $this->title->getDBkey() ),
-                               __METHOD__,
+                               $fname,
                                array( 'ORDER BY' => 'oi_timestamp DESC' )
                        );
                }