grepBench

perl -Mstrict -wE'
use Benchmark qw(:all);

my $arr1 = [ 1 .. 10_000 ];
my $arr2 = [ 1 .. 10_000 ];
my $arr3 = [ 1 .. 10_000 ];

cmpthese(-3, {
    inPlace => sub {
        @$arr1 = grep { $_ ne "100" } @$arr1;
    },
    newArray => sub {
        $arr2 =  [ grep { $_ ne "100" } @$arr2 ];
    },
    newArray2 => sub {
        $arr3 =  sub {\@_}->(grep { $_ ne "100" } @$arr3);
    }
});
'
#
#
            Rate   inPlace  newArray newArray2
inPlace    377/s        --      -22%      -72%
newArray   486/s       29%        --      -64%
newArray2 1334/s      254%      174%        --