Win8 Strawberry 5.8.9.5 (32)  Thu 10/07/2021 16:15:36
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings -l
my $futile = 'a' x 10_000;

print 'start     ', scalar time;
die 'huh?' if $futile =~
    /a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*a*b/
    ;
print 'post rx 1 ', scalar time;
die 'huh?' if $futile =~
    /(?:(?:(?:(?:(?:(?:(?:(?:(?:(?:(?:(?:(?:a*)*)*)*)*)*)*)*)*)*)*)*)*)*b/
    ;
print 'post rx 2 ', scalar time;
print 'done      ', scalar time;
^Z
start     1633637901
post rx 1 1633637901
post rx 2 1633637901
done      1633637901