Is fsockopen generally slow?

Question

I am trying to perform a downstream bandwidth speed test in PHP. I dunno why wget would download 1 Mbyte data in 400 Mbps while fsockopen does it in 170 Mbps. I am using fsockopen since it is supported on all servers.

Does any one know why? 400 Mbps vs. 170 Mbps is quite a big difference.

Is there a better option for performance?

<?php
      $url = 'http://ftp.sunet.se/pub/Linux/distributions/ubuntu/ubuntu/dists/hardy-backports/Contents-i386.gz';
      $size = 1024*1024; // Get amount of bytes

      $parts = parse_url($url);
      $fp = fsockopen($parts['host'], isset($parts['port']) ? $parts['port'] : 80, $errno, $errstr, 30);

      if (!$fp) throw new Exception("Problem with $url, $errstr");

      $out = "GET " . $parts['path'] ." HTTP/1.1\r\n"
           . "Host: ". $parts['host'] ."\r\n"
           . "Connection: Close\r\n\r\n";

      fwrite($fp, $out);

      $found_body = false;
      $response = '';
      $start = microtime(true);
      $timeout = 30;

      while (!feof($fp)) {
        if ((microtime(true) - $start) > $timeout) break;
        if (strlen($response) > $size) break;
        //$row = fgets($fp, 128); // Grab block of 128
        $row = fgets($fp);
        if ($found_body) {
          $response .= $row;
        } else if ($row == "\r\n") {
          $found_body = true;
          $tsStart = microtime(true);
          continue;
        }
      }

      $time_elapsed = microtime(true) - $tsStart;

      $speed = strlen($response) / $time_elapsed * 8 / 1000000;

      echo round($speed, 2) . ' Mbps ('. strlen($response) .' bytes in '. round($time_elapsed, 3) .' s)<br />';

?>

score 4 · Answer 1 · answered Jan 23 '12 at 19:57

4

It's not fsockopen that's slow - it's PHP in general. Try increasing the buffer size in your fgets() calls and use a regular expression to find the end of the headers. With your current code, you're executing your read loop too many times and network IO is no longer your bottleneck.

answered Jan 23 '12 at 19:57

Cal

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A great answer however it didn't improve anything. Fact is the most optimal packet size is 64-128. Higher or lower than that changes performance drasticly to the worse. I ran the tests ~10 times and they all turned out the same way. – tim Jan 23 '12 at 20:33
since you're not actually using the repsonse, try throwing away the data after you read it to avoid having to constantly re-alloc memory by doing the string concats. that might also be burning time here – Cal Jan 23 '12 at 22:11
Instead of storing the response in a buffer I do $response_amount += strlen(row);. I spontanously feel it might have gained 5-10% performance increase. However time to time the performance is slower. That can depend on the individual call itself. Could be a step forward. Good thinking. – tim Jan 23 '12 at 22:55

score -2 · Answer 2 · answered Jan 23 '12 at 15:58

-2

It would be much easier (and probably faster) to use file_get_contents() for this.

answered Jan 23 '12 at 15:58

FtDRbwLXw6

27,774
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Thats not supported by allow_url_fopen = false – tim Jan 23 '12 at 16:23
@user1135440: If `allow_url_fopen` was set to `false`, then the OP wouldn't be able to use `fopen()` in this way either. And since he's complaining about the performance, and not a PHP Fatal Error, it's obvious that his `allow_url_fopen` is not set to `false`. – FtDRbwLXw6 Jan 23 '12 at 16:27
allow_url_fopen does not apply to fsockopen. – tim May 30 '12 at 09:20

Is fsockopen generally slow?

2 Answers2