I assume you are aware of the Benchmark module? It allows you to check which parts of your code are slow.

Particularly put a benchmark around each of these lines:

    my $oExcel = Spreadsheet::ParseExcel->new();

    my $oBook = $oExcel->Parse($filesToBeProcessed[$x]);

    my $oWkS = $oBook->{Worksheet}[1];
    
    my @data = getFieldData($oWkS);
[download]

and you'll probably be able to see the "guilty" party.

Liz