Well, then try the following script 
my $max = 50000;
my @l = ('a'..'z');
my @keys = map { join '', map $l[rand @l], 0..71 } 0..$max;

[download]
On my system running this script with a perlmalloc-built perl is 600x (!) faster than with a sysmalloc-built perl: 
$ time /usr/local/src/perl-5.10.0-perlmalloc/perl -I/usr/local/src/per
+l-5.10.0-perlmalloc/lib ~/trash/slow_malloc2.pl
3.027u 0.435s 0:03.68 93.7%     1448+324155k 0+0io 0pf+0w

$ time /usr/local/src/perl-5.10.0-sysmalloc/perl -I/usr/local/src/perl
+-5.10.0-sysmalloc/lib ~/trash/slow_malloc2.pl
405.090u 189.574s 13:01.52 76.0%        1466+495449k 0+0io 0pf+0w

[download]
This is a pathological case, but this may happen with FreeBSD's malloc.

In reply to Re^3: 5:10: Why is this slower than 5.8.8? by eserte
in thread 5:10: Why is this slower than 5.8.8? by jk2addict

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