http://www.perlmonks.org?node_id=1001085


in reply to Re^6: How to compare 3 lists
in thread How to compare 3 lists

Ok, then my approach is of no use in your case. Please use roboticus solution. I don't understand now how do you find snapshots 1-6. Are those the first 6 entries on master? So you could think about not scanning whole files, only 6 entries of master and as many from slaves as needed (date check) - in case the files are huge.