PHPExcel Writer 对象最终使用巨大的内存和超时

Question

我正在使用以下方法创建一个 excel 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

我正在从数据库中获取 35000 行（大部分为空），其中包含 79 列，并写入 Excel 文件 (Excel5)。

它适用于 30000 行，峰值内存使用量为 1.44GB，文件大小为 24MB。但是当我去 35000 它超时说，

致命错误：E:\XAMPP\htdocs\ProjectName\application\libraries\PHPExcel\Writer\Excel5\BIFFwriter.php 第 144 行内存不足（已分配 1780219904）（试图分配 17301483 字节）

当我创建 PHPExcel 对象时，它最终会使用大量内存并超时。我在 php.ini 文件中设置了 "memory_limit= -1" 和 "ma​​x_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是这样的

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和执行时间？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

您正在使用 phptemp 进行缓存，但需要设置

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

这意味着 PHPExcel 在开始使用 phptemp 进行缓存之前将使用 5000MB (5GB) 的 PHP 内存.....如果您有 php.ini 最大内存设置允许 PHP 使用，我会感到惊讶这么多内存

您应该为memoryCacheSize 使用低得多的值，也许是512MB，这意味着PHPExcel 在切换到使用php://temp 之前将只使用512MB 的PHP 内存来缓存单元格数据