sub qshuf {
     my %hash;
     sort { $hash{$a}{$b}||=(.5 <=> rand 1) } @_;
}

##</code><code>##

sub qshuf {
     my %hash;
     sort { ($hash{$a}||=rand 1) <=> ($hash{$b}||=rand 1) } @_;
}

         Rate  xform  slice  shufl  qshuf
xform  65.6/s     --   -34%   -72%  -100%
slice  99.7/s    52%     --   -57%  -100%
shufl   233/s   255%   133%     --   -99%
qshuf 44494/s 67764% 44534% 19019%     --

permutation |  slice |  xform |  shufl |  qshuf
--------------------------------------------------
Std. Dev.   | 69.974 | 58.895 | 53.532 | 62.689