pocketmine\level\format\mcregion\RegionLoader::doSlowCleanUp PHP Метод

    public function doSlowCleanUp()
    {
        for ($i = 0; $i < 1024; ++$i) {
            if ($this->locationTable[$i][0] === 0 or $this->locationTable[$i][1] === 0) {
                continue;
            }
            fseek($this->filePointer, $this->locationTable[$i][0] << 12);
            $chunk = fread($this->filePointer, $this->locationTable[$i][1] << 12);
            $length = Binary::readInt(substr($chunk, 0, 4));
            if ($length <= 1) {
                $this->locationTable[$i] = [0, 0, 0];
                //Non-generated chunk, remove it from index
            }
            try {
                $chunk = zlib_decode(substr($chunk, 5));
            } catch (Throwable $e) {
                $this->locationTable[$i] = [0, 0, 0];
                //Corrupted chunk, remove it
                continue;
            }
            $chunk = chr(self::COMPRESSION_ZLIB) . zlib_encode($chunk, ZLIB_ENCODING_DEFLATE, 9);
            $chunk = Binary::writeInt(strlen($chunk)) . $chunk;
            $sectors = (int) ceil(strlen($chunk) / 4096);
            if ($sectors > $this->locationTable[$i][1]) {
                $this->locationTable[$i][0] = $this->lastSector + 1;
                $this->lastSector += $sectors;
            }
            fseek($this->filePointer, $this->locationTable[$i][0] << 12);
            fwrite($this->filePointer, str_pad($chunk, $sectors << 12, "", STR_PAD_RIGHT));
        }
        $this->writeLocationTable();
        $n = $this->cleanGarbage();
        $this->writeLocationTable();
        return $n;
    }