你可以通过执行下面的代码来增加php脚本的内存:

ini_set('memory_limit','-1'); // enabled the full memory available.

并且在脚本中取消分配不需要的变量。

如果你想读取大文件，你应该一点一点地读取，而不是一次读取。 这是一个简单的数学:如果您一次读取一个1mb大的文件，那么同时至少需要1mb的内存来保存数据。

所以你应该使用fopen & fread一点一点地阅读它们。

It is unfortunately easy to program in PHP in a way that consumes memory faster than you realise. Copying strings, arrays and objects instead of using references will do it, though PHP 5 is supposed to do this more automatically than in PHP 4. But dealing with your data set in entirety over several steps is also wasteful compared to processing the smallest logical unit at a time. The classic example is working with large resultsets from a database: most programmers fetch the entire resultset into an array and then loop over it one or more times with foreach(). It is much more memory efficient to use a while() loop to fetch and process one row at a time. The same thing applies to processing a file.

做的事情:

ini_set('memory_limit', '-1');

从来都不是好事。如果你想读取一个很大的文件，最好的做法是一点一点地复制它。尝试以下代码进行最佳实践。

$path = 'path_to_file_.txt';

$file = fopen($path, 'r');
$len = 1024; // 1MB is reasonable for me. You can choose anything though, but do not make it too big
$output = fread( $file, $len );

while (!feof($file)) {
    $output .= fread( $file, $len );
}

fclose($file);

echo 'Output is: ' . $output;

ini_set('memory_limit', '-1');

你可以通过执行下面的代码来增加php脚本的内存:

ini_set('memory_limit','-1'); // enabled the full memory available.

并且在脚本中取消分配不需要的变量。