spout_reader_caching.php

<?php

require_once __DIR__.'/vendor/autoload.php';

use Box\Spout\Writer\WriterFactory;
use Box\Spout\Reader\ReaderFactory;
use Box\Spout\Common\Type;

$rows = 2000;
$columns = 50;

if(!is_file('test.xlsx')) {
    $writerXlsx = WriterFactory::create(Type::XLSX);
    $writerXlsx->setShouldUseInlineStrings(false);
    $writerXlsx->openToFile('test.xlsx');
    for($r=1; $r<=$rows; $r+=1) {
        $row=[];
        for($c=1; $c<=$columns; $c+=1) {
            $row[] = $c . '_' . uniqid();
        }
        $writerXlsx->addRow($row);
    }
    $writerXlsx->close();
}

$start = microtime(true);

ini_set('memory_limit', '800M');
$reader = ReaderFactory::create(Type::XLSX);
$reader->open('test.xlsx');
foreach ($reader->getSheetIterator() as $sheet) {
    foreach ($sheet->getRowIterator() as $row) {}
}
$reader->close();

$end = microtime(true);

print $end-$start.' seconds '.PHP_EOL;