What is the advantage of echo fragments when outputting a file?

Question

What is the advantage and difference between the following:

Statement 1:

header("Content-type: image/jpeg");
header('Expires: ' . date('r',time() + 864000));
header("Pragma: public");
header("Cache-Control: public");
header("Content-Length: " . strlen($contents));
$splitString = str_split($contents, 1024);
foreach($splitString as $chunk)
echo $chunk;

Statement 2:

header("Content-type: image/jpeg");
header('Expires: ' . date('r',time() + 864000));
header("Pragma: public");
header("Cache-Control: public");
header("Content-Length: " . strlen($contents));
echo $contents;

Answer 1

Because TCP / IP packets are buffered, using them echoto send large strings to a client can cause severe performance degradation. Sometimes it can add a whole second to script processing time. This happens even when using output buffering.

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Answer 2

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Answer 3

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Answer 4

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