Problem with pThreads

gistfile1.php

<?php

	define('INDEXER_THREADS',	2);
	define('READER_THREADS',	2);

	define('START_DIR', 		'r:/big');
	define('READ_SIZE',		    1024);

	/**
	 * Executor
	 */
	class Executor extends Worker {
		/**
		 */
		public function __construct() {
		}
	}


	/**
	 * Iterates over a directory, adding files to the file queue and directories to the directory queue
	 * @property Executor $worker
	 */
	class AsyncIndexer extends Collectable {

		/** @var string */
		public $Path;

		/** @var string[] */
		public $tDirpaths = [ ];

		/** @var string[] */
		public $tFilepaths = [ ];

		/** @var string */
		public $Path2 = '';

		/**
		 * @param string $Path
		 */
		public function __construct($Path) {
			$this->Path = $Path;
			$this->tDirpaths = [ ];
			$this->tFilePaths = [ ];
		}

		public function run() {
			printf("%s submitted for indexing\n", $this->Path);

			foreach(new DirectoryIterator($this->Path) as $objFile) {
				if($objFile->isDot())
					continue;
				if($objFile->isDir()) {
					array_push($this->tDirpaths, $objFile->getPathname());
					echo "Adding {$objFile->getPathname()} to tDirpaths.\n";
					$this->Path2 = $objFile->getPathname();
				}
//				else if($objFile->isFile())
//					$this->tFilepaths[] = $objFile->getPathname();
			}
			var_dump($this);
			echo "Exit loop {$this->Path}\n";

			$this->setGarbage();
		}
	}

	/**
	 * Reads the given file in chunks
	 */
	class AsyncReader extends Collectable {
		/** @var string */
		protected $Path;

		/**
		 * @param string $Path
		 */
		public function __construct($Path) {
			$this->Path = $Path;
		}

		public function run() {
			sprintf("Starting read of File %s in chunks of %d\n", $this->Path, READ_SIZE);

			$fh = fopen($this->Path, 'r', false);
			while(!feof($fh)) {
				$d = fread($fh, READ_SIZE);
			}
			fclose($fh);
			sprintf("Completed read of File %s\n", $this->Path);

			$this->setGarbage();
		}
	}

	/**
	 * MyPool
	 *
	 * @property float $WorkRemaining	The number of items in the work queue
	 */
	class MyPool extends Pool {
		/**
		 * @param string $Name
		 *
		 * @return int|null
		 */
		public function __get($Name) {
			if($Name === 'WorkRemaining')
				return count($this->work);
			return NULL;
		}
	}

	$Started = microtime(true);
	$IndexerPool = new MyPool(INDEXER_THREADS, 'Executor');
	$ReaderPool = new MyPool(READER_THREADS, 'Executor');

	$IndexerPool->submit(new AsyncIndexer(START_DIR));

	sleep(5);
	while(true) {
		echo "Collecting...\n";
		$IndexerPool->collect(function (AsyncIndexer $worker) use ($IndexerPool, $ReaderPool) {
			echo "Collect(): on $worker->Path\n";
			var_dump($worker);
//			while(count($worker->tDirpaths)) {
//				$Dirpath = array_shift($worker->tDirpaths);
//				echo "Creating new AsyncIndexer for {$Dirpath}\n";
//				$IndexerPool->submit(new AsyncIndexer($Dirpath));
//			}
			if($worker->isGarbage()) {
				echo "{$worker->Path} isGarbage...\n";
				return true;
			}
			return false;
//			return $worker->isGarbage();
		});
		$ReaderPool->collect(function (AsyncReader $worker) {
			return $worker->isGarbage();
		});
		if($IndexerPool->WorkRemaining === 0 && $ReaderPool->WorkRemaining === 0) {
			printf('$IndexerPool and $ReaderPool indicate no more work remaining, ending.'.PHP_EOL);
			break;
		}
		printf("Sleeping... Indexer=%d, Reader=%d\n", $IndexerPool->WorkRemaining, $ReaderPool->WorkRemaining);
		sleep(1);
	}

	$IndexerPool->shutdown();
	echo '$IndexerPool shutdown...'.PHP_EOL;

	$ReaderPool->shutdown();
	echo '$ReaderPool shutdown...'.PHP_EOL;

//	$TotalTime = 0;
//	$pool->collect(function (AsyncExec $work) use(&$TotalTime, &$TotalSize) {
//		if($work->isGarbage()) {
//			printf("$work->Path: Completed in %.2f seconds.\n", $work->Ended - $work->Started);
//			$TotalTime += $work->Ended - $work->Started;
//			$TotalSize += $work->Size;
////			var_dump($work);
////			foreach($work->tOutput as $Line)
////				printf("   %d: %s\n", $work->num, $Line);
//			return true;
//		}
//		return false;
//	});
//	printf("Copied %sMB in %.2fs at %sMBps using %d threads.\n", number_format(MB($TotalSize), 2), $TotalTime, number_format(MB($TotalSize) / $TotalTime, 2), POOL_THREADS);

	/**
	 * @param integer $x
	 *
	 * @return float
	 */
	function MB($x) { return $x / 1024 / 1024; }

	/**
	 * Timer, keeps track of start time and has properties to get timing results
	 */
	class Timer {

		/** @var float */
		protected $Started;

		/**
		 * Constructor
		 */
		public function __construct() {
			$this->Started = microtime(true);
		}

		/**
		 * @param string $Name
		 *
		 * @return float|null
		 */
		public function __get($Name='') {
			switch($Name) {
				case 'Elapsed':
					return microtime(true) - $this->Started;
			}
			return NULL;
		}
	}

Having trouble with the array in Async indexer on line #54, the array is not being modified either with array_push() nor with traditional ->tDirpaths[] = 'xyz';

On line #61 the var_dump indicates that the $tDirpaths has no entries.

Running the entire code the echo's on Line #55 shows that it is getting the data.

Any ideas?