| Index: trunk/phase3/includes/db/Database.php |
| — | — | @@ -257,9 +257,11 @@ |
| 258 | 258 | * @param failFunction |
| 259 | 259 | * @param $flags |
| 260 | 260 | * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php |
| | 261 | + * @param int $max, max connection attempts |
| | 262 | + ** After the first retry (second attempt), each retry waits 1 second |
| 261 | 263 | */ |
| 262 | 264 | function __construct( $server = false, $user = false, $password = false, $dbName = false, |
| 263 | | - $failFunction = false, $flags = 0, $tablePrefix = 'get from global' ) { |
| | 265 | + $failFunction = false, $flags = 0, $tablePrefix = 'get from global', $max = false ) { |
| 264 | 266 | |
| 265 | 267 | global $wgOut, $wgDBprefix, $wgCommandLineMode; |
| 266 | 268 | # Can't get a reference if it hasn't been set yet |
| — | — | @@ -293,7 +295,7 @@ |
| 294 | 296 | } |
| 295 | 297 | |
| 296 | 298 | if ( $server ) { |
| 297 | | - $this->open( $server, $user, $password, $dbName ); |
| | 299 | + $this->open( $server, $user, $password, $dbName, $max ); |
| 298 | 300 | } |
| 299 | 301 | } |
| 300 | 302 | |
| — | — | @@ -311,7 +313,7 @@ |
| 312 | 314 | * Usually aborts on failure |
| 313 | 315 | * If the failFunction is set to a non-zero integer, returns success |
| 314 | 316 | */ |
| 315 | | - function open( $server, $user, $password, $dbName ) { |
| | 317 | + function open( $server, $user, $password, $dbName, $max = false ) { |
| 316 | 318 | global $wguname, $wgAllDBsAreLocalhost; |
| 317 | 319 | wfProfileIn( __METHOD__ ); |
| 318 | 320 | |
| — | — | @@ -343,11 +345,11 @@ |
| 344 | 346 | |
| 345 | 347 | wfProfileIn("dbconnect-$server"); |
| 346 | 348 | |
| 347 | | - # Try to connect up to three times |
| | 349 | + if( !$max ) { $max = 3; } |
| | 350 | + # Try to connect up to three times (by default) |
| 348 | 351 | # The kernel's default SYN retransmission period is far too slow for us, |
| 349 | 352 | # so we use a short timeout plus a manual retry. |
| 350 | 353 | $this->mConn = false; |
| 351 | | - $max = 3; |
| 352 | 354 | $this->installErrorHandler(); |
| 353 | 355 | for ( $i = 0; $i < $max && !$this->mConn; $i++ ) { |
| 354 | 356 | if ( $i > 1 ) { |
| Index: trunk/phase3/includes/db/LoadBalancer.php |
| — | — | @@ -11,6 +11,8 @@ |
| 12 | 12 | * @ingroup Database |
| 13 | 13 | */ |
| 14 | 14 | class LoadBalancer { |
| | 15 | + const GRACEFUL = 1; |
| | 16 | + |
| 15 | 17 | /* private */ var $mServers, $mConns, $mLoads, $mGroupLoads; |
| 16 | 18 | /* private */ var $mFailFunction, $mErrorConnection; |
| 17 | 19 | /* private */ var $mReadIndex, $mLastIndex, $mAllowLagged; |
| — | — | @@ -171,7 +173,7 @@ |
| 172 | 174 | * |
| 173 | 175 | * Side effect: opens connections to databases |
| 174 | 176 | */ |
| 175 | | - function getReaderIndex( $group = false, $wiki = false ) { |
| | 177 | + function getReaderIndex( $group = false, $wiki = false, $attempts = false ) { |
| 176 | 178 | global $wgReadOnly, $wgDBClusterTimeout, $wgDBAvgStatusPoll, $wgDBtype; |
| 177 | 179 | |
| 178 | 180 | # FIXME: For now, only go through all this for mysql databases |
| — | — | @@ -248,7 +250,7 @@ |
| 249 | 251 | } |
| 250 | 252 | |
| 251 | 253 | wfDebugLog( 'connect', __METHOD__.": Using reader #$i: {$this->mServers[$i]['host']}...\n" ); |
| 252 | | - $conn = $this->openConnection( $i, $wiki ); |
| | 254 | + $conn = $this->openConnection( $i, $wiki, $attempts ); |
| 253 | 255 | |
| 254 | 256 | if ( !$conn ) { |
| 255 | 257 | wfDebugLog( 'connect', __METHOD__.": Failed connecting to $i/$wiki\n" ); |
| — | — | @@ -399,8 +401,13 @@ |
| 400 | 402 | /** |
| 401 | 403 | * Get a connection by index |
| 402 | 404 | * This is the main entry point for this class. |
| | 405 | + * @param int $i Database |
| | 406 | + * @param array $groups Query groups |
| | 407 | + * @param string $wiki Wiki ID |
| | 408 | + * @param int $attempts Max DB connect attempts |
| | 409 | + * @param int $flags |
| 403 | 410 | */ |
| 404 | | - public function &getConnection( $i, $groups = array(), $wiki = false ) { |
| | 411 | + public function &getConnection( $i, $groups = array(), $wiki = false, $attempts = false, $flags = 0 ) { |
| 405 | 412 | global $wgDBtype; |
| 406 | 413 | wfProfileIn( __METHOD__ ); |
| 407 | 414 | |
| — | — | @@ -432,7 +439,7 @@ |
| 433 | 440 | |
| 434 | 441 | # Operation-based index |
| 435 | 442 | if ( $i == DB_SLAVE ) { |
| 436 | | - $i = $this->getReaderIndex( false, $wiki ); |
| | 443 | + $i = $this->getReaderIndex( false, $wiki, $attempts ); |
| 437 | 444 | } elseif ( $i == DB_LAST ) { |
| 438 | 445 | # Just use $this->mLastIndex, which should already be set |
| 439 | 446 | $i = $this->mLastIndex; |
| — | — | @@ -444,12 +451,15 @@ |
| 445 | 452 | } |
| 446 | 453 | # Couldn't find a working server in getReaderIndex()? |
| 447 | 454 | if ( $i === false ) { |
| | 455 | + if( $flags && self::GRACEFUL ) { |
| | 456 | + return false; |
| | 457 | + } |
| 448 | 458 | $this->reportConnectionError( $this->mErrorConnection ); |
| 449 | 459 | } |
| 450 | 460 | |
| 451 | 461 | # Now we have an explicit index into the servers array |
| 452 | | - $conn = $this->openConnection( $i, $wiki ); |
| 453 | | - if ( !$conn ) { |
| | 462 | + $conn = $this->openConnection( $i, $wiki, $attempts ); |
| | 463 | + if ( !$conn && !($flags & self::GRACEFUL) ) { |
| 454 | 464 | $this->reportConnectionError( $this->mErrorConnection ); |
| 455 | 465 | } |
| 456 | 466 | |
| — | — | @@ -509,11 +519,12 @@ |
| 510 | 520 | * |
| 511 | 521 | * @param integer $i Server index |
| 512 | 522 | * @param string $wiki Wiki ID to open |
| | 523 | + * @param int $attempts Maximum connection attempts |
| 513 | 524 | * @return Database |
| 514 | 525 | * |
| 515 | 526 | * @access private |
| 516 | 527 | */ |
| 517 | | - function openConnection( $i, $wiki = false ) { |
| | 528 | + function openConnection( $i, $wiki = false, $attempts = false ) { |
| 518 | 529 | wfProfileIn( __METHOD__ ); |
| 519 | 530 | if ( $wiki !== false ) { |
| 520 | 531 | $conn = $this->openForeignConnection( $i, $wiki ); |
| — | — | @@ -525,7 +536,7 @@ |
| 526 | 537 | } else { |
| 527 | 538 | $server = $this->mServers[$i]; |
| 528 | 539 | $server['serverIndex'] = $i; |
| 529 | | - $conn = $this->reallyOpenConnection( $server ); |
| | 540 | + $conn = $this->reallyOpenConnection( $server, false, $attempts ); |
| 530 | 541 | if ( $conn->isOpen() ) { |
| 531 | 542 | $this->mConns['local'][$i][0] = $conn; |
| 532 | 543 | } else { |
| — | — | @@ -628,7 +639,7 @@ |
| 629 | 640 | * Returns a Database object whether or not the connection was successful. |
| 630 | 641 | * @access private |
| 631 | 642 | */ |
| 632 | | - function reallyOpenConnection( $server, $dbNameOverride = false ) { |
| | 643 | + function reallyOpenConnection( $server, $dbNameOverride = false, $attempts = false ) { |
| 633 | 644 | if( !is_array( $server ) ) { |
| 634 | 645 | throw new MWException( 'You must update your load-balancing configuration. See DefaultSettings.php entry for $wgDBservers.' ); |
| 635 | 646 | } |
| — | — | @@ -643,7 +654,7 @@ |
| 644 | 655 | |
| 645 | 656 | # Create object |
| 646 | 657 | wfDebug( "Connecting to $host $dbname...\n" ); |
| 647 | | - $db = new $class( $host, $user, $password, $dbname, 1, $flags ); |
| | 658 | + $db = new $class( $host, $user, $password, $dbname, 1, $flags, 'get from global', $attempts ); |
| 648 | 659 | if ( $db->isOpen() ) { |
| 649 | 660 | wfDebug( "Connected\n" ); |
| 650 | 661 | } else { |
| Index: trunk/phase3/includes/Revision.php |
| — | — | @@ -719,20 +719,13 @@ |
| 720 | 720 | $flags = Revision::compressRevisionText( $data ); |
| 721 | 721 | |
| 722 | 722 | # Write to external storage if required |
| 723 | | - if ( $wgDefaultExternalStore ) { |
| 724 | | - if ( is_array( $wgDefaultExternalStore ) ) { |
| 725 | | - // Distribute storage across multiple clusters |
| 726 | | - $store = $wgDefaultExternalStore[mt_rand(0, count( $wgDefaultExternalStore ) - 1)]; |
| 727 | | - } else { |
| 728 | | - $store = $wgDefaultExternalStore; |
| 729 | | - } |
| | 723 | + if( $wgDefaultExternalStore ) { |
| 730 | 724 | // Store and get the URL |
| 731 | | - $data = ExternalStore::insert( $store, $data ); |
| 732 | | - if ( !$data ) { |
| 733 | | - # This should only happen in the case of a configuration error, where the external store is not valid |
| 734 | | - throw new MWException( "Unable to store text to external storage $store" ); |
| | 725 | + $data = ExternalStore::randomInsert( $data ); |
| | 726 | + if( !$data ) { |
| | 727 | + throw new MWException( "Unable to store text to external storage" ); |
| 735 | 728 | } |
| 736 | | - if ( $flags ) { |
| | 729 | + if( $flags ) { |
| 737 | 730 | $flags .= ','; |
| 738 | 731 | } |
| 739 | 732 | $flags .= 'external'; |
| Index: trunk/phase3/includes/ExternalStore.php |
| — | — | @@ -14,7 +14,7 @@ |
| 15 | 15 | */ |
| 16 | 16 | class ExternalStore { |
| 17 | 17 | /* Fetch data from given URL */ |
| 18 | | - static function fetchFromURL($url) { |
| | 18 | + static function fetchFromURL( $url ) { |
| 19 | 19 | global $wgExternalStores; |
| 20 | 20 | |
| 21 | 21 | if( !$wgExternalStores ) |
| — | — | @@ -44,7 +44,7 @@ |
| 45 | 45 | |
| 46 | 46 | $class = 'ExternalStore' . ucfirst( $proto ); |
| 47 | 47 | /* Any custom modules should be added to $wgAutoLoadClasses for on-demand loading */ |
| 48 | | - if( !class_exists( $class ) ){ |
| | 48 | + if( !class_exists( $class ) ) { |
| 49 | 49 | return false; |
| 50 | 50 | } |
| 51 | 51 | |
| — | — | @@ -66,4 +66,41 @@ |
| 67 | 67 | return $store->store( $params, $data ); |
| 68 | 68 | } |
| 69 | 69 | } |
| | 70 | + |
| | 71 | + /** |
| | 72 | + * Like insert() above, but does more of the work for us. |
| | 73 | + * This function does not need a url param, it builds it by |
| | 74 | + * itself. It also fails-over to the next possible clusters. |
| | 75 | + * |
| | 76 | + * @param string $data |
| | 77 | + * Returns the URL of the stored data item, or false on error |
| | 78 | + */ |
| | 79 | + public static function randomInsert( $data ) { |
| | 80 | + global $wgDefaultExternalStore; |
| | 81 | + $tryStorages = (array)$wgDefaultExternalStore; |
| | 82 | + // Do not wait and do second retry per master if we |
| | 83 | + // have other active cluster masters to try instead. |
| | 84 | + $retry = count($tryStorages) > 1 ? false : true; |
| | 85 | + while ( count($tryStorages) > 0 ) { |
| | 86 | + $index = mt_rand(0, count( $tryStorages ) - 1); |
| | 87 | + $storeUrl = $tryStorages[$index]; |
| | 88 | + list( $proto, $params ) = explode( '://', $storeUrl, 2 ); |
| | 89 | + $store = self::getStoreObject( $proto ); |
| | 90 | + if ( $store === false ) { |
| | 91 | + throw new MWException( "Invalid external storage protocol - $storeUrl" ); |
| | 92 | + return false; |
| | 93 | + } else { |
| | 94 | + $url = $store->store( $params, $data, $retry ); // Try to save the object |
| | 95 | + if ( $url ) { |
| | 96 | + return $url; // Done! |
| | 97 | + } else { |
| | 98 | + unset( $tryStorages[$index] ); // Don't try this one again! |
| | 99 | + sort( $tryStorages ); // Must have consecutive keys |
| | 100 | + wfDebugLog( 'ExternalStorage', "Unable to store text to external storage $storeUrl" ); |
| | 101 | + } |
| | 102 | + } |
| | 103 | + } |
| | 104 | + throw new MWException( "Unable to store text to external storage" ); |
| | 105 | + return false; // All cluster masters dead :( |
| | 106 | + } |
| 70 | 107 | } |
| Index: trunk/phase3/includes/ExternalStoreDB.php |
| — | — | @@ -34,13 +34,16 @@ |
| 35 | 35 | /** @todo Document.*/ |
| 36 | 36 | function &getSlave( $cluster ) { |
| 37 | 37 | $lb =& $this->getLoadBalancer( $cluster ); |
| 38 | | - return $lb->getConnection( DB_SLAVE ); |
| | 38 | + // Make only two connection attempts, since we still have the master to try |
| | 39 | + return $lb->getConnection( DB_SLAVE, array(), false, 2 ); |
| 39 | 40 | } |
| 40 | 41 | |
| 41 | 42 | /** @todo Document.*/ |
| 42 | | - function &getMaster( $cluster ) { |
| | 43 | + function &getMaster( $cluster, $retry = true ) { |
| 43 | 44 | $lb =& $this->getLoadBalancer( $cluster ); |
| 44 | | - return $lb->getConnection( DB_MASTER ); |
| | 45 | + // Make only two connection attempts if there are other clusters to try |
| | 46 | + $attempts = $retry ? false : 2; |
| | 47 | + return $lb->getConnection( DB_MASTER, array(), false, $attempts, LoadBalancer::GRACEFUL ); |
| 45 | 48 | } |
| 46 | 49 | |
| 47 | 50 | /** @todo Document.*/ |
| — | — | @@ -56,7 +59,7 @@ |
| 57 | 60 | * Fetch data from given URL |
| 58 | 61 | * @param string $url An url of the form DB://cluster/id or DB://cluster/id/itemid for concatened storage. |
| 59 | 62 | */ |
| 60 | | - function fetchFromURL($url) { |
| | 63 | + function fetchFromURL( $url ) { |
| 61 | 64 | $path = explode( '/', $url ); |
| 62 | 65 | $cluster = $path[2]; |
| 63 | 66 | $id = $path[3]; |
| — | — | @@ -119,15 +122,17 @@ |
| 120 | 123 | * |
| 121 | 124 | * @param $cluster String: the cluster name |
| 122 | 125 | * @param $data String: the data item |
| | 126 | + * @param $retry bool: allows an extra DB connection retry after 1 second |
| 123 | 127 | * @return string URL |
| 124 | 128 | */ |
| 125 | | - function store( $cluster, $data ) { |
| 126 | | - $fname = 'ExternalStoreDB::store'; |
| 127 | | - |
| 128 | | - $dbw =& $this->getMaster( $cluster ); |
| 129 | | - |
| | 129 | + function store( $cluster, $data, $retry = true ) { |
| | 130 | + if( !$dbw = $this->getMaster( $cluster, $retry ) ) { |
| | 131 | + return false; // failed, maybe another cluster is up... |
| | 132 | + } |
| 130 | 133 | $id = $dbw->nextSequenceValue( 'blob_blob_id_seq' ); |
| 131 | | - $dbw->insert( $this->getTable( $dbw ), array( 'blob_id' => $id, 'blob_text' => $data ), $fname ); |
| | 134 | + $dbw->insert( $this->getTable( $dbw ), |
| | 135 | + array( 'blob_id' => $id, 'blob_text' => $data ), |
| | 136 | + __METHOD__ ); |
| 132 | 137 | $id = $dbw->insertId(); |
| 133 | 138 | if ( $dbw->getFlag( DBO_TRX ) ) { |
| 134 | 139 | $dbw->immediateCommit(); |