php gzip xml file (53MB) casue Out of memory error

i have a 53 MB xml file that i want to gzip.

The code below gzip it

$gzFile = "my.gz";

        $data = IMPLODE("", FILE($filename)); 
        $gzdata = GZENCODE($data, 9); 

        //open gz -- 'w9' is highest compression
        $fp = gzopen ($gzFile, 'w9');       
        //loop through array and write each line into the compressed file       
        gzwrite ($fp, $gzdata);

        //close the file
        gzclose ($fp);

This cause

PHP Fatal error:  Out of memory (allocated 70516736)开发者_运维百科 (tried to allocate 24 bytes) 

Any one have any suggestions.

I already have increase the memory in php.ini

---

Increase the memory even further, or don't use PHP:

exec('gzip input_file.xml output_file.gzip');