I did a bit more digging, and thought this might help...
You could use the following code (straight from the Benchmark docs) to reassure yourself that the networked access is the bottleneck.

use Benchmark;
$t0 = new Benchmark;

# ... your code here ...
# system("dir", "/s", "path_to_root_sgml_dir\\*.sgml");

$t1 = new Benchmark;
$td = timediff($t1, $t0);
print "the code took:",timestr($td),"\n";
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Oh, and welcome to the monastery!