From: Aaron Schulz <aschulz@wikimedia.org>
Date: Sun, 19 May 2013 20:15:50 +0000 (-0700)
Subject: Made SwiftFileBackend::loadObjectListing() populate stat entries in reverse order.
X-Git-Tag: 1.31.0-rc.0~19471^2
X-Git-Url: http://git.cyclocoop.org/%7B%24www_url%7Dadmin/compta/exercices/?a=commitdiff_plain;h=01b564403e4f12978ad1f941b680633a4eb77952;p=lhc%2Fweb%2Fwiklou.git

Made SwiftFileBackend::loadObjectListing() populate stat entries in reverse order.

Change-Id: I07bf9c852729d65cee72364ca3249e31936d0562
---

diff --git a/includes/filebackend/SwiftFileBackend.php b/includes/filebackend/SwiftFileBackend.php
index f9e2ce47d9..54a90d32f5 100644
--- a/includes/filebackend/SwiftFileBackend.php
+++ b/includes/filebackend/SwiftFileBackend.php
@@ -1111,7 +1111,11 @@ class SwiftFileBackend extends FileBackendStore {
 		$names = array();
 		$storageDir = rtrim( $params['dir'], '/' );
 		$suffixStart = ( $dir === '' ) ? 0 : strlen( $dir ) + 1; // size of "path/to/dir/"
-		foreach ( $cfObjects as $object ) {
+		// Iterate over the list *backwards* as this primes the stat cache, which is LRU.
+		// If this fills the cache and the caller stats an uncached file before stating
+		// the ones on the listing, there would be zero cache hits if this went forwards.
+		for ( end( $cfObjects ); key( $cfObjects ) !== null; prev( $cfObjects ) ) {
+			$object = current( $cfObjects );
 			$path = "{$storageDir}/" . substr( $object->name, $suffixStart );
 			$val = array(
 				// Convert dates like "Tue, 03 Jan 2012 22:01:04 GMT" to TS_MW
@@ -1122,7 +1126,7 @@ class SwiftFileBackend extends FileBackendStore {
 			$this->cheapCache->set( $path, 'stat', $val );
 			$names[] = $object->name;
 		}
-		return $names;
+		return array_reverse( $names ); // keep the paths in original order
 	}
 
 	/**