From f8af77dd9dd59b2aeaf849596d0d2fb14fe46675 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Tue, 30 Apr 2013 18:42:03 -0700
Subject: [PATCH] Reduced memory usage a bit for copyFileBackend.php with
 --missingonly.

Change-Id: Iae650b5c3a5f99c5b2e31e29c276957ea6b8bb50
---
 maintenance/copyFileBackend.php | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/maintenance/copyFileBackend.php b/maintenance/copyFileBackend.php
index f2c4ac5414..fe422b38a3 100644
--- a/maintenance/copyFileBackend.php
+++ b/maintenance/copyFileBackend.php
@@ -79,24 +79,28 @@ class CopyFileBackend extends Maintenance {
 
 			// Do a listing comparison if specified
 			if ( $this->hasOption( 'missingonly' ) ) {
-				$relFilesSrc = array();
-				$relFilesDst = array();
-				foreach ( $srcPathsRel as $srcPathRel ) {
-					$relFilesSrc[] = $srcPathRel;
-				}
 				$dstPathsRel = $dst->getFileList( array(
 					'dir' => $dst->getRootStoragePath() . "/$backendRel" ) );
 				if ( $dstPathsRel === null ) {
 					$this->error( "Could not list files in $container.", 1 ); // die
 				}
+				// Get the list of destination files
+				$relFilesDstSha1 = array();
 				foreach ( $dstPathsRel as $dstPathRel ) {
-					$relFilesDst[] = $dstPathRel;
+					$relFilesDstSha1[sha1( $dstPathRel )] = 1;
+				}
+				unset( $dstPathsRel ); // free
+				// Get the list of missing files
+				$missingPathsRel = array();
+				foreach ( $srcPathsRel as $srcPathRel ) {
+					if ( !isset( $relFilesDstSha1[sha1( $srcPathRel )] ) ) {
+						$missingPathsRel[] = $srcPathRel;
+					}
 				}
+				unset( $srcPathsRel ); // free
 				// Only copy the missing files over in the next loop
-				$srcPathsRel = array_diff( $relFilesSrc, $relFilesDst );
+				$srcPathsRel = $missingPathsRel;
 				$this->output( count( $srcPathsRel ) . " file(s) need to be copied.\n" );
-				unset( $relFilesSrc );
-				unset( $relFilesDst );
 			}
 
 			$batchPaths = array();
-- 
2.20.1