You sure as hell don't need Cuckoo, errr, notPerl "6", or anything other than Perl to write clean, fast, correct, parallel code that can be used today in performance-critical environments, aka Real Life.

Why can't you just be positive? Always so negative!

I hadn't heard about MCE yet. By the looks of it, it has taken the ideas I had when I implemented the forks and ThreadPool modules to the next level. Kudos to Mario Roy.

Now to get back to your example, but then in Perl 6:

use MyClient;

my $client = MyClient.new;

my $list = $client.call('ListCustomers');
$list.parse_json_payload;

say "Start: Found $list.payload.totalCount() accounts";

my %results;

for $list.payload.items -> $account {
    my $id = $account.id;
    say "Deleting $id";

    my $call = $client->call('DeleteCustomer', account_id => $id);
    say 'Status: ' . $call.status;

    $call.status == 204 ?? %results<OK>++ !! %results<NOT_OK>++;
}

say "Results: %results.perl()"
[download]

To make this run on multiple CPU's, one basically needs to do only one thing: prefix the for with a hyper;

hyper for $list.payload.items -> $account {
[download]

There is however one caveat: hashes in Perl 6 are not thread safe in the sense that they might lose updates when being updated from multiple threads. If you're just interested in number of successes / fails, why not make it two counters instead of elements in a hash? When updating integers from multiple threads, you should use atomic integers (otherwise you would have the same problem as with the hash elements). So the code becomes:

use MyClient;

my $client = MyClient.new;

my $list = $client.call('ListCustomers');
$list.parse_json_payload;

say "Start: Found $list.payload.totalCount() accounts";

my atomicint $ok;
my atomicint $not-ok;

hyper for $list.payload.items -> $account {
    my $id = $account.id;
    say "Deleting $id";

    my $call = $client->call('DeleteCustomer', account_id => $id);
    say 'Status: ' . $call.status;

    $call.status == 204 ?? atomic-inc-fetch($ok) !! atomic-inc-fetch($
+not-ok)
}

say "Results: ok = $ok, not-ok = $not-ok"
[download]

I've used the ASCII equivalent of the atomic increment operator, since PerlMonks does not display the unicode equivalent "++⚛️" inside code blocks properly.

So I would argue three things here:

1. Perl 6 has less boilerplate to begin with (no use statements needed)
2. Perl 6 needs less boilerplate to parallelize (just adding "hyper" will do in many cases
3. Some thought needs to go into updating data structures from multiple threads at the same time

Note that the Perl 5 solution to updating shared data structures requires tieing and locking, neither of which is good for performance. The Perl 6 solution using atomic increment is lockless and uses hardware features of the CPU.

Hope this clarifies.

EDIT: fixed $results{} -> %results<> non-migrato, haj++

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.