Question

I am using 2 php libraries to serve files- unzip, and dUnzip2

zip zip.lib
http://www.zend.com/codex.php?id=470&single=1

They work fine on files under 10MB , but with files over 10MB, I have to set the mem limit to 256. With files over 25MB, I set it to 512. It seems kind of high… Is it?

I’m on a dedicated server- 4 CPU’s and 16GB RAM – but we also have a lot of traffic and downloading, so I’m kind of wondering here.

Answer 1

Perhaps you’re using php to load the whole files into memory before serving them to the user? I’ve used a function found at http://www.php.net/manual/en/function.readfile.php (comments section) that serves the file in parts, keeping memory low. Copying from that post (because my version is changed):

<?php 
    function readfile_chunked ($filename,$type='array') { 
      $chunk_array=array(); 
      $chunksize = 1*(1024*1024); // how many bytes per chunk 
      $buffer = ''; 
      $handle = fopen($filename, 'rb'); 
      if ($handle === false) { 
       return false; 
      } 
      while (!feof($handle)) { 
          switch($type) 
          { 
              case'array': 
              // Returns Lines Array like file() 
              $lines[] = fgets($handle, $chunksize); 
              break; 
              case'string': 
              // Returns Lines String like file_get_contents() 
              $lines = fread($handle, $chunksize); 
              break; 
          } 
      } 
       fclose($handle); 
       return $lines; 
    } 
?>