[me@first ~]$ ./perl-json-test.pl
                      Rate  enc+dec hashref  enc+dec arrayref
enc+dec hashref   344063/s                --              -22%
enc+dec arrayref  438597/s               27%                --

[me@second ~]$ ./perl-json-test.pl
                      Rate  enc+dec hashref  enc+dec arrayref
enc+dec hashref   153121/s                --              -24%
enc+dec arrayref  200972/s               31%                --