I was able to reproduce the problem with rakudo 2016.01.1 on Linux. It seems to be fixed now (maybe with rakudo commit 241e5e5847):
$ ls -lh 126372.data -rw-r--r-- 2 christian christian 48M Apr 11 14:07 126372.data $ time ./perl6-m -e 'my $content = slurp "126372.data", :bin; say $content.elems' 49430132 real 0m0.225s user 0m0.172s sys 0m0.048s $ ./perl6-m --version This is Rakudo version 2016.03-110-g5bfc8fb built on MoarVM version 2016.03-104-g10d3971 implementing Perl 6.c. I'm closing this ticket as 'resolved'.
