PHPExcel Writer对象最终会占用大量内存和超时

Question

我正在使用以下方式创建Excel工作表：

1. Codeigniter 2.2.1
2. PHP 5.4.25
3. Apache 2.4.7
4. XAMPP 1.8.2
5. PHPExcel 1.8.0

我从数据库中获取 35000行（大部分为空） 79列并写入excel文件（Excel5）。

适用于30000行，峰值内存使用量为 1.44GB ，文件大小为24MB。但是当我去35000时，它说出来了，

致命错误：第144行的E：\ XAMPP \ htdocs \ ProjectName \ application \ libraries \ PHPExcel \ Writer \ Excel5 \ BIFFwriter.php内存不足（已分配1780219904）（尝试分配17301483字节）< /强>

当我创建PHPExcel对象时，它最终会占用大量内存和超时。我在php.ini文件中设置了“ memory_limit = -1 ”和“ max_execution_time = 1000 ”，并在PHPExcel中尝试了不同的缓存存储方法。

我在控制器中的算法看起来像这样

public function write_controller() {    
    error_reporting(E_ALL);
    ini_set("display_errors", 1);
    ini_set('memory_limit', '-1'); //-1 for unlimited memory
    $dir = "assets/output/";

    //FIRST CHECK IF PREVIOUS FILE EXISTS OR NOT
    $this->clear_directory($dir);

    // Loading PHPExcel library
    $this->load->library('PHPExcel');
    $this->load->library('PHPExcel/IOFactory');

    $cacheMethod = PHPExcel_CachedObjectStorageFactory::cache_to_phpTemp;
    $cacheSettings = array('memoryCacheSize' => '5000MB', 'cacheTime' => '1000'); 

    PHPExcel_Settings::setCacheStorageMethod($cacheMethod, $cacheSettings);

    //First Create the xls file and then insert rest of the data
    $objPHPExcel = new PHPExcel();
    $objPHPExcel->getProperties()->setTitle("export")->setDescription("none");

    //activate sheet number 1
    $objPHPExcel->setActiveSheetIndex(0);

    //Setting font styles
    $objPHPExcel->getActiveSheet()->getDefaultStyle()->getFont()->setName('Arial')->setSize(8)->setBold(false);

    //Setting number format as TEXT
    $objPHPExcel->getActiveSheet()->getDefaultStyle()->getNumberFormat()->setFormatCode(PHPExcel_Style_NumberFormat::FORMAT_TEXT);

    //Freezing first top row
    $objPHPExcel->getActiveSheet()->freezePane('A2');


    $objWorksheet = $objPHPExcel->getActiveSheet();

    $row1 = 1;

    $objWorksheet->setCellValueByColumnAndRow(0, $row1, "Site name");
    $objWorksheet->setCellValueByColumnAndRow(1, $row1, "Vendor_1");
    $objWorksheet->setCellValueByColumnAndRow(2, $row1, "Status");
    $objWorksheet->setCellValueByColumnAndRow(3, $row1, "Easting");
    $objWorksheet->setCellValueByColumnAndRow(4, $row1, "Northing");
    $objWorksheet->setCellValueByColumnAndRow(5, $row1, "Sector_1");
    .
    .
    .
    //Rest of the 74 columns

    $style = array(
        'alignment' => array(
            'horizontal' => PHPExcel_Style_Alignment::HORIZONTAL_CENTER, 
            'vertical' => PHPExcel_Style_Alignment::VERTICAL_CENTER)
    );

    $objWorksheet->getDefaultStyle()->applyFromArray($style);

    $objWriter = IOFactory::createWriter($objPHPExcel, 'Excel5');

    $saved_location ='assets/output/Piano11.xls'; 
    $objWriter->save($saved_location); 

    //Now reading the saved xls file
    $objReader = new PHPExcel_Reader_Excel5();

    $newPHPExcel = $objReader->load($saved_location); 

    $newWorksheet = $newPHPExcel->getActiveSheet();

    //Now insert rest of the data from Piano table which will come from database
    $table_name = 'piano_test';

    $query = $this->db->get('tbl_piano');

    if (!$query) {
        return false;
    }

    // Fetching the data from table
    $fields = $query->list_fields();

    $row = 2;
    foreach ($query->result() as $data) {
        set_time_limit(0);
        $col = 0;
        foreach ($fields as $field) {
            $newWorksheet->setCellValueByColumnAndRow($col, $row, $data->$field); //<- This skips leading 0s
            $col++;
        }
        $row++;
    }

    $newobjWriter = IOFactory::createWriter($newPHPExcel, 'Excel5');
    $newobjWriter->save('assets/output/Piano11.xls');

    echo 'Memory peak usage: <b>'.$this->convert(memory_get_peak_usage(true)).'</b><br/>';
    gc_collect_cycles();//garbage collector
    echo 'inserted.';
}

任何解决方案如何最大限度地减少内存使用量？执行时间处理时间？或任何其他替代解决方案？或者我应该改变我的算法吗？

Answer 1

您使用phptemp进行缓存，但使用设置

$cacheSettings = array('memoryCacheSize' => '5000MB', 'cacheTime' => '1000'); 

这意味着PHPExcel在开始使用phptemp进行缓存之前会使用5000MB（5GB）的PHP内存.....如果你有php.ini最大内存设置允许PHP使用，我会感到惊讶那么多记忆

你应该为memoryCacheSize使用更低的值，也许是512MB，这意味着PHPExcel在切换到使用php：// temp <之前只会使用512MB的PHP内存来缓存单元格数据/ p>