usage: showsamples.pl [-Bbdl] <srcix>|all <dstix>|all
   show database records for given site indices
       -B        show both srcix -> dstix and dstix -> srcix
       -b        show bandwidth
       -d        show delay (the default)
       -l        show loss
       -n <num>  show only the last <num> records
       -S <time> show records no later than unix timestamp <time>

usage: showsamples.pl -e pid/eid
   show mapping of name->ix for all plab nodes in <pid>/<eid>