Perl脚本如何知道自己的内存占用？

use Devel::Size qw(size total_size);

my %hash = (
    key1 => 'value1',
    key2 => 'value2',
);

my $size = size(\%hash);
print "Memory usage: $size bytes\n";

use Devel::Dump::Stats;

my %hash = (
    key1 => 'value1',
    key2 => 'value2',
);

my $stats = Devel::Dump::Stats->new(\%hash);
print $stats->report;

use Devel::Peek;

my %hash = (
    key1 => 'value1',
    key2 => 'value2',
);

Dump(\%hash);

use Devel::MAT;

my %hash = (
    key1 => 'value1',
    key2 => 'value2',
);

my $dumper = Devel::MAT->new;
my $dump = $dumper->dump(
    \%hash,
    name => 'my_hash',
);

$dump->save('my_hash.mat');

use Devel::NYTProf;

my %hash = (
    key1 => 'value1',
    key2 => 'value2',
);

Devel::NYTProf::start('/path/to/output.nytprof');
# Your code here
Devel::NYTProf::stop();

cpan install Devel::Size