Avoid useless delay and master connections in wfWaitForSlaves() in runJobs.php

[lhc/web/wiklou.git] / includes / GlobalFunctions.php

diff --git a/includes/GlobalFunctions.php b/includes/GlobalFunctions.php
index d0af179..fc99b58 100644 (file)
--- a/includes/GlobalFunctions.php
+++ b/includes/GlobalFunctions.php
@@ -3798,11 +3798,14 @@ function wfGetNull() {
  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
  * a no-op if there are no slaves.
  *
- * @param int|bool $maxLag (deprecated)
+ * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
  */
-function wfWaitForSlaves( $maxLag = false, $wiki = false, $cluster = false ) {
+function wfWaitForSlaves( $ifWritesSince = false, $wiki = false, $cluster = false ) {
+       // B/C: first argument used to be "max seconds of lag"; ignore such values
+       $ifWritesSince = ( $ifWritesSince > 1e9 ) ? $ifWritesSince : false;
+
        if ( $cluster !== false ) {
                $lb = wfGetLBFactory()->getExternalLB( $cluster );
        } else {
@@ -3812,7 +3815,13 @@ function wfWaitForSlaves( $maxLag = false, $wiki = false, $cluster = false ) {
        // bug 27975 - Don't try to wait for slaves if there are none
        // Prevents permission error when getting master position
        if ( $lb->getServerCount() > 1 ) {
+               if ( $ifWritesSince && !$lb->isOpen( DB_MASTER ) ) {
+                       return; // assume no writes done
+               }
                $dbw = $lb->getConnection( DB_MASTER, array(), $wiki );
+               if ( $ifWritesSince && $dbw->lastDoneWrites() < $ifWritesSince ) {
+                       return; // no writes since the last wait
+               }
                $pos = $dbw->getMasterPos();
                // The DBMS may not support getMasterPos() or the whole
                // load balancer might be fake (e.g. $wgAllDBsAreLocalhost).