PHP - 如何在Windows上写入大量具有性能的文件

Question

I have a big gzipped file (~15Gb compressed, ~88 uncompressed) and I need to "explode" the content to a large amount of files. For example, if I read the following line :

foo    property.content    "I'm the content of the string."

I need to create a file named foo.db and store inside :

property.content    "I'm the content of the string."

I've succeed to get that. But i have performances issues. I think is maybe because of the large amount of file. (~31k files created in 60 seconds) but i don't sure. This is why I'm here.

My code is reading each piece of 1048576 bytes (of the gz file with gzread) and sort the content in an Array to write all content one time by file. Then, i made a foreach loop to read the content of my cache, open the specific file and write into. For exemple if my cache look like this :

$cache = array(
    "file_one" => "property.content    \"I'm the content of the string.\"
                   property.foo    \"I'm the content of another string.\"",
    "file_two" => "property.foobar    \"I'm the content of the another string.\"",
    "file_three" => ...
);

The loop make this :

foreach ($cache as $file => $content) {

    $filesrc = $file . ".db";
    $fp = fopen($filesrc,"a");
    fwrite($fp,$content."
");
    fclose($fp);

}

With this method, i read ~65Mb and write ~31k files in 60 seconds. If i read all the content in one file, I wrote ~220Mb in 60 seconds.

There is something to do to improve the performances and create the small files ? I'm using PHP 5.5.1 with Apache 2.4.6 on Windows and I'm using CLI to this script.

Edit : This is a log to get the time profile of each loop, for 131072 bytes of data readed : http://pastebin.com/uRPFfywY