Assuming it works on your OS and for your particular file, the following code will be faster than either of your options above: 
sysread SITE, my $xml, -s SITE;

[download]
See the discussion (including benchmarks) at Slurp a file

-Blake

In reply to Re: Reading entire file into scalar: speed differences? by blakem
in thread Reading entire file into scalar: speed differences? by theguvnor

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