[ViewVC] Diff of: cvs/AnyEvent-MP/MP.pm

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

…		…
11	NODE $port # returns the noderef of the port	11	NODE $port # returns the noderef of the port
12		12
13	$SELF # receiving/own port id in rcv callbacks	13	$SELF # receiving/own port id in rcv callbacks
14		14
15	# initialise the node so it can send/receive messages	15	# initialise the node so it can send/receive messages
16	initialise_node; # -OR-	16	initialise_node;
17	initialise_node "localhost:4040"; # -OR-
18	initialise_node "slave/", "localhost:4040"
19		17
20	# ports are message endpoints	18	# ports are message endpoints
21		19
22	# sending messages	20	# sending messages
23	snd $port, type => data...;	21	snd $port, type => data...;
24	snd $port, @msg;	22	snd $port, @msg;
25	snd @msg_with_first_element_being_a_port;	23	snd @msg_with_first_element_being_a_port;
26		24
27	# creating/using miniports	25	# creating/using ports, the simple way
28	my $miniport = port { my @msg = @_; 0 };	26	my $simple_port = port { my @msg = @_; 0 };
29		27
30	# creating/using full ports	28	# creating/using ports, tagged message matching
31	my $port = port;	29	my $port = port;
32	rcv $port, smartmatch => $cb->(@msg);
33	rcv $port, ping => sub { snd $_[0], "pong"; 0 };	30	rcv $port, ping => sub { snd $_[0], "pong"; 0 };
34	rcv $port, pong => sub { warn "pong received\n"; 0 };	31	rcv $port, pong => sub { warn "pong received\n"; 0 };
35
36	# more, smarter, matches (_any_ is exported by this module)
37	rcv $port, [child_died => $pid] => sub { ...
38	rcv $port, [_any_, _any_, 3] => sub { .. $_[2] is 3
39		32
40	# create a port on another node	33	# create a port on another node
41	my $port = spawn $node, $initfunc, @initdata;	34	my $port = spawn $node, $initfunc, @initdata;
42		35
43	# monitoring	36	# monitoring
…		…
74		67
75	=item port	68	=item port
76		69
77	A port is something you can send messages to (with the C<snd> function).	70	A port is something you can send messages to (with the C<snd> function).
78		71
79	Some ports allow you to register C<rcv> handlers that can match specific	72	Ports allow you to register C<rcv> handlers that can match all or just
80	messages. All C<rcv> handlers will receive messages they match, messages	73	some messages. Messages will not be queued.
81	will not be queued.
82		74
83	=item port id - C<noderef#portname>	75	=item port ID - C<noderef#portname>
84		76
85	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as	77	A port ID is the concatenation of a noderef, a hash-mark (C<#>) as
86	separator, and a port name (a printable string of unspecified format). An	78	separator, and a port name (a printable string of unspecified format). An
87	exception is the the node port, whose ID is identical to its node	79	exception is the the node port, whose ID is identical to its node
88	reference.	80	reference.
89		81
90	=item node	82	=item node
91		83
92	A node is a single process containing at least one port - the node	84	A node is a single process containing at least one port - the node port,
93	port. You can send messages to node ports to find existing ports or to	85	which provides nodes to manage each other remotely, and to create new
94	create new ports, among other things.	86	ports.
95		87
96	Nodes are either private (single-process only), slaves (connected to a	88	Nodes are either private (single-process only), slaves (can only talk to
97	master node only) or public nodes (connectable from unrelated nodes).	89	public nodes, but do not need an open port) or public nodes (connectable
		90	from any other node).
98		91
99	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	92	=item node ID - C<[a-za-Z0-9_\-.:]+>
100		93
101	A node reference is a string that either simply identifies the node (for	94	A node ID is a string that either simply identifies the node (for
102	private and slave nodes), or contains a recipe on how to reach a given	95	private and slave nodes), or contains a recipe on how to reach a given
103	node (for public nodes).	96	node (for public nodes).
104		97
105	This recipe is simply a comma-separated list of C<address:port> pairs (for	98	This recipe is simply a comma-separated list of C<address:port> pairs (for
106	TCP/IP, other protocols might look different).	99	TCP/IP, other protocols might look different).
…		…
132	use base "Exporter";	125	use base "Exporter";
133		126
134	our $VERSION = $AnyEvent::MP::Kernel::VERSION;	127	our $VERSION = $AnyEvent::MP::Kernel::VERSION;
135		128
136	our @EXPORT = qw(	129	our @EXPORT = qw(
137	NODE $NODE *SELF node_of _any_	130	NODE $NODE *SELF node_of after
138	resolve_node initialise_node	131	resolve_node initialise_node
139	snd rcv mon kil reg psub spawn	132	snd rcv mon mon_guard kil reg psub spawn
140	port	133	port
141	);	134	);
142		135
143	our $SELF;	136	our $SELF;
144		137
…		…
148	kil $SELF, die => $msg;	141	kil $SELF, die => $msg;
149	}	142	}
150		143
151	=item $thisnode = NODE / $NODE	144	=item $thisnode = NODE / $NODE
152		145
153	The C<NODE> function returns, and the C<$NODE> variable contains	146	The C<NODE> function returns, and the C<$NODE> variable contains the
154	the noderef of the local node. The value is initialised by a call	147	node id of the local node. The value is initialised by a call to
155	to C<become_public> or C<become_slave>, after which all local port	148	C<initialise_node>.
156	identifiers become invalid.
157		149
158	=item $noderef = node_of $port	150	=item $nodeid = node_of $port
159		151
160	Extracts and returns the noderef from a portid or a noderef.	152	Extracts and returns the noderef from a port ID or a node ID.
161		153
162	=item initialise_node $noderef, $seednode, $seednode...	154	=item initialise_node $profile_name
163
164	=item initialise_node "slave/", $master, $master...
165		155
166	Before a node can talk to other nodes on the network it has to initialise	156	Before a node can talk to other nodes on the network it has to initialise
167	itself - the minimum a node needs to know is it's own name, and optionally	157	itself - the minimum a node needs to know is it's own name, and optionally
168	it should know the noderefs of some other nodes in the network.	158	it should know the noderefs of some other nodes in the network.
169		159
170	This function initialises a node - it must be called exactly once (or	160	This function initialises a node - it must be called exactly once (or
171	never) before calling other AnyEvent::MP functions.	161	never) before calling other AnyEvent::MP functions.
172		162
173	All arguments are noderefs, which can be either resolved or unresolved.	163	All arguments (optionally except for the first) are noderefs, which can be
		164	either resolved or unresolved.
		165
		166	The first argument will be looked up in the configuration database first
		167	(if it is C<undef> then the current nodename will be used instead) to find
		168	the relevant configuration profile (see L<aemp>). If none is found then
		169	the default configuration is used. The configuration supplies additional
		170	seed/master nodes and can override the actual noderef.
174		171
175	There are two types of networked nodes, public nodes and slave nodes:	172	There are two types of networked nodes, public nodes and slave nodes:
176		173
177	=over 4	174	=over 4
178		175
179	=item public nodes	176	=item public nodes
180		177
181	For public nodes, C<$noderef> must either be a (possibly unresolved)	178	For public nodes, C<$noderef> (supplied either directly to
182	noderef, in which case it will be resolved, or C<undef> (or missing), in	179	C<initialise_node> or indirectly via a profile or the nodename) must be a
183	which case the noderef will be guessed.	180	noderef (possibly unresolved, in which case it will be resolved).
184		181
185	Afterwards, the node will bind itself on all endpoints and try to connect	182	After resolving, the node will bind itself on all endpoints.
186	to all additional C<$seednodes> that are specified. Seednodes are optional
187	and can be used to quickly bootstrap the node into an existing network.
188		183
189	=item slave nodes	184	=item slave nodes
190		185
191	When the C<$noderef> is the special string C<slave/>, then the node will	186	When the C<$noderef> (either as given or overriden by the config file)
		187	is the special string C<slave/>, then the node will become a slave
192	become a slave node. Slave nodes cannot be contacted from outside and will	188	node. Slave nodes cannot be contacted from outside, and cannot talk to
193	route most of their traffic to the master node that they attach to.	189	each other (at least in this version of AnyEvent::MP).
194		190
195	At least one additional noderef is required: The node will try to connect	191	Slave nodes work by creating connections to all public nodes, using the
196	to all of them and will become a slave attached to the first node it can	192	L<AnyEvent::MP::Global> service.
197	successfully connect to.
198		193
199	=back	194	=back
200		195
201	This function will block until all nodes have been resolved and, for slave	196	After initialising itself, the node will connect to all additional
202	nodes, until it has successfully established a connection to a master	197	C<$seednodes> that are specified diretcly or via a profile. Seednodes are
203	server.	198	optional and can be used to quickly bootstrap the node into an existing
		199	network.
204		200
		201	All the seednodes will also be specially marked to automatically retry
		202	connecting to them indefinitely, so make sure that seednodes are really
		203	reliable and up (this might also change in the future).
		204
205	Example: become a public node listening on the default node.	205	Example: become a public node listening on the guessed noderef, or the one
		206	specified via C<aemp> for the current node. This should be the most common
		207	form of invocation for "daemon"-type nodes.
206		208
207	initialise_node;	209	initialise_node;
		210
		211	Example: become a slave node to any of the the seednodes specified via
		212	C<aemp>. This form is often used for commandline clients.
		213
		214	initialise_node "slave/";
208		215
209	Example: become a public node, and try to contact some well-known master	216	Example: become a public node, and try to contact some well-known master
210	servers to become part of the network.	217	servers to become part of the network.
211		218
212	initialise_node undef, "master1", "master2";	219	initialise_node undef, "master1", "master2";
…		…
215		222
216	initialise_node 4041;	223	initialise_node 4041;
217		224
218	Example: become a public node, only visible on localhost port 4044.	225	Example: become a public node, only visible on localhost port 4044.
219		226
220	initialise_node "locahost:4044";	227	initialise_node "localhost:4044";
221
222	Example: become a slave node to any of the specified master servers.
223
224	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
225		228
226	=item $cv = resolve_node $noderef	229	=item $cv = resolve_node $noderef
227		230
228	Takes an unresolved node reference that may contain hostnames and	231	Takes an unresolved node reference that may contain hostnames and
229	abbreviated IDs, resolves all of them and returns a resolved node	232	abbreviated IDs, resolves all of them and returns a resolved node
…		…
266	=item snd $port, type => @data	269	=item snd $port, type => @data
267		270
268	=item snd $port, @msg	271	=item snd $port, @msg
269		272
270	Send the given message to the given port ID, which can identify either	273	Send the given message to the given port ID, which can identify either
271	a local or a remote port, and can be either a string or soemthignt hat	274	a local or a remote port, and must be a port ID.
272	stringifies a sa port ID (such as a port object :).
273		275
274	While the message can be about anything, it is highly recommended to use a	276	While the message can be about anything, it is highly recommended to use a
275	string as first element (a portid, or some word that indicates a request	277	string as first element (a port ID, or some word that indicates a request
276	type etc.).	278	type etc.).
277		279
278	The message data effectively becomes read-only after a call to this	280	The message data effectively becomes read-only after a call to this
279	function: modifying any argument is not allowed and can cause many	281	function: modifying any argument is not allowed and can cause many
280	problems.	282	problems.
…		…
285	that Storable can serialise and deserialise is allowed, and for the local	287	that Storable can serialise and deserialise is allowed, and for the local
286	node, anything can be passed.	288	node, anything can be passed.
287		289
288	=item $local_port = port	290	=item $local_port = port
289		291
290	Create a new local port object that can be used either as a pattern	292	Create a new local port object and returns its port ID. Initially it has
291	matching port ("full port") or a single-callback port ("miniport"),	293	no callbacks set and will throw an error when it receives messages.
292	depending on how C<rcv> callbacks are bound to the object.
293		294
294	=item $port = port { my @msg = @_; $finished }	295	=item $local_port = port { my @msg = @_ }
295		296
296	Creates a "miniport", that is, a very lightweight port without any pattern	297	Creates a new local port, and returns its ID. Semantically the same as
297	matching behind it, and returns its ID. Semantically the same as creating
298	a port and calling C<rcv $port, $callback> on it.	298	creating a port and calling C<rcv $port, $callback> on it.
299		299
300	The block will be called for every message received on the port. When the	300	The block will be called for every message received on the port, with the
301	callback returns a true value its job is considered "done" and the port	301	global variable C<$SELF> set to the port ID. Runtime errors will cause the
302	will be destroyed. Otherwise it will stay alive.	302	port to be C<kil>ed. The message will be passed as-is, no extra argument
		303	(i.e. no port ID) will be passed to the callback.
303		304
304	The message will be passed as-is, no extra argument (i.e. no port id) will	305	If you want to stop/destroy the port, simply C<kil> it:
305	be passed to the callback.
306		306
307	If you need the local port id in the callback, this works nicely:	307	my $port = port {
308		308	my @msg = @_;
309	my $port; $port = port {	309	...
310	snd $otherport, reply => $port;	310	kil $SELF;
311	};	311	};
312		312
313	=cut	313	=cut
314		314
315	sub rcv($@);	315	sub rcv($@);
		316
		317	sub _kilme {
		318	die "received message on port without callback";
		319	}
316		320
317	sub port(;&) {	321	sub port(;&) {
318	my $id = "$UNIQ." . $ID++;	322	my $id = "$UNIQ." . $ID++;
319	my $port = "$NODE#$id";	323	my $port = "$NODE#$id";
320		324
321	if (@_) {	325	rcv $port, shift \|\| \&_kilme;
322	rcv $port, shift;
323	} else {
324	$PORT{$id} = sub { }; # nop
325	}
326		326
327	$port	327	$port
328	}	328	}
329		329
330	=item reg $port, $name
331
332	=item reg $name
333
334	Registers the given port (or C<$SELF><<< if missing) under the name
335	C<$name>. If the name already exists it is replaced.
336
337	A port can only be registered under one well known name.
338
339	A port automatically becomes unregistered when it is killed.
340
341	=cut
342
343	sub reg(@) {
344	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
345
346	$REG{$_[0]} = $port;
347	}
348
349	=item rcv $port, $callback->(@msg)	330	=item rcv $local_port, $callback->(@msg)
350		331
351	Replaces the callback on the specified miniport (after converting it to	332	Replaces the default callback on the specified port. There is no way to
352	one if required).	333	remove the default callback: use C<sub { }> to disable it, or better
353		334	C<kil> the port when it is no longer needed.
354	=item rcv $port, tagstring => $callback->(@msg), ...
355
356	=item rcv $port, $smartmatch => $callback->(@msg), ...
357
358	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
359
360	Register callbacks to be called on matching messages on the given full
361	port (after converting it to one if required) and return the port.
362
363	The callback has to return a true value when its work is done, after
364	which is will be removed, or a false value in which case it will stay
365	registered.
366		335
367	The global C<$SELF> (exported by this module) contains C<$port> while	336	The global C<$SELF> (exported by this module) contains C<$port> while
368	executing the callback.	337	executing the callback. Runtime errors during callback execution will
		338	result in the port being C<kil>ed.
369		339
370	Runtime errors during callback execution will result in the port being	340	The default callback received all messages not matched by a more specific
371	C<kil>ed.	341	C<tag> match.
372		342
373	If the match is an array reference, then it will be matched against the	343	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
374	first elements of the message, otherwise only the first element is being
375	matched.
376		344
377	Any element in the match that is specified as C<_any_> (a function	345	Register (or replace) callbacks to be called on messages starting with the
378	exported by this module) matches any single element of the message.	346	given tag on the given port (and return the port), or unregister it (when
		347	C<$callback> is C<$undef> or missing). There can only be one callback
		348	registered for each tag.
379		349
380	While not required, it is highly recommended that the first matching	350	The original message will be passed to the callback, after the first
381	element is a string identifying the message. The one-string-only match is	351	element (the tag) has been removed. The callback will use the same
382	also the most efficient match (by far).	352	environment as the default callback (see above).
383		353
384	Example: create a port and bind receivers on it in one go.	354	Example: create a port and bind receivers on it in one go.
385		355
386	my $port = rcv port,	356	my $port = rcv port,
387	msg1 => sub { ...; 0 },	357	msg1 => sub { ... },
388	msg2 => sub { ...; 0 },	358	msg2 => sub { ... },
389	;	359	;
390		360
391	Example: create a port, bind receivers and send it in a message elsewhere	361	Example: create a port, bind receivers and send it in a message elsewhere
392	in one go:	362	in one go:
393		363
394	snd $otherport, reply =>	364	snd $otherport, reply =>
395	rcv port,	365	rcv port,
396	msg1 => sub { ...; 0 },	366	msg1 => sub { ... },
397	...	367	...
398	;	368	;
		369
		370	Example: temporarily register a rcv callback for a tag matching some port
		371	(e.g. for a rpc reply) and unregister it after a message was received.
		372
		373	rcv $port, $otherport => sub {
		374	my @reply = @_;
		375
		376	rcv $SELF, $otherport;
		377	};
399		378
400	=cut	379	=cut
401		380
402	sub rcv($@) {	381	sub rcv($@) {
403	my $port = shift;	382	my $port = shift;
404	my ($noderef, $portid) = split /#/, $port, 2;	383	my ($noderef, $portid) = split /#/, $port, 2;
405		384
406	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	385	$NODE{$noderef} == $NODE{""}
407	or Carp::croak "$port: rcv can only be called on local ports, caught";	386	or Carp::croak "$port: rcv can only be called on local ports, caught";
408		387
409	if (@_ == 1) {	388	while (@_) {
		389	if (ref $_[0]) {
		390	if (my $self = $PORT_DATA{$portid}) {
		391	"AnyEvent::MP::Port" eq ref $self
		392	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		393
		394	$self->[2] = shift;
		395	} else {
410	my $cb = shift;	396	my $cb = shift;
411	delete $PORT_DATA{$portid};
412	$PORT{$portid} = sub {	397	$PORT{$portid} = sub {
413	local $SELF = $port;	398	local $SELF = $port;
414	eval {	399	eval { &$cb }; _self_die if $@;
415	&$cb	400	};
416	and kil $port;
417	};	401	}
418	_self_die if $@;	402	} elsif (defined $_[0]) {
419	};
420	} else {
421	my $self = $PORT_DATA{$portid} \|\|= do {	403	my $self = $PORT_DATA{$portid} \|\|= do {
422	my $self = bless {	404	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
423	id => $port,
424	}, "AnyEvent::MP::Port";
425		405
426	$PORT{$portid} = sub {	406	$PORT{$portid} = sub {
427	local $SELF = $port;	407	local $SELF = $port;
428		408
429	eval {
430	for (@{ $self->{rc0}{$_[0]} }) {	409	if (my $cb = $self->[1]{$_[0]}) {
431	$_ && &{$_->[0]}	410	shift;
432	&& undef $_;	411	eval { &$cb }; _self_die if $@;
433	}	412	} else {
434
435	for (@{ $self->{rcv}{$_[0]} }) {
436	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
437	&& &{$_->[0]}	413	&{ $self->[0] };
438	&& undef $_;
439	}
440
441	for (@{ $self->{any} }) {
442	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
443	&& &{$_->[0]}
444	&& undef $_;
445	}	414	}
446	};	415	};
447	_self_die if $@;	416
		417	$self
448	};	418	};
449		419
450	$self
451	};
452
453	"AnyEvent::MP::Port" eq ref $self	420	"AnyEvent::MP::Port" eq ref $self
454	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	421	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
455		422
456	while (@_) {
457	my ($match, $cb) = splice @_, 0, 2;	423	my ($tag, $cb) = splice @_, 0, 2;
458		424
459	if (!ref $match) {	425	if (defined $cb) {
460	push @{ $self->{rc0}{$match} }, [$cb];	426	$self->[1]{$tag} = $cb;
461	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
462	my ($type, @match) = @$match;
463	@match
464	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
465	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
466	} else {	427	} else {
467	push @{ $self->{any} }, [$cb, $match];	428	delete $self->[1]{$tag};
468	}	429	}
469	}	430	}
470	}	431	}
471		432
472	$port	433	$port
…		…
527	will arrive, or the monitoring action will be invoked after possible	488	will arrive, or the monitoring action will be invoked after possible
528	message loss has been detected. No messages will be lost "in between"	489	message loss has been detected. No messages will be lost "in between"
529	(after the first lost message no further messages will be received by the	490	(after the first lost message no further messages will be received by the
530	port). After the monitoring action was invoked, further messages might get	491	port). After the monitoring action was invoked, further messages might get
531	delivered again.	492	delivered again.
		493
		494	Note that monitoring-actions are one-shot: once released, they are removed
		495	and will not trigger again.
532		496
533	In the first form (callback), the callback is simply called with any	497	In the first form (callback), the callback is simply called with any
534	number of C<@reason> elements (no @reason means that the port was deleted	498	number of C<@reason> elements (no @reason means that the port was deleted
535	"normally"). Note also that I<< the callback B<must> never die >>, so use	499	"normally"). Note also that I<< the callback B<must> never die >>, so use
536	C<eval> if unsure.	500	C<eval> if unsure.
…		…
697	my $id = "$RUNIQ." . $ID++;	661	my $id = "$RUNIQ." . $ID++;
698		662
699	$_[0] =~ /::/	663	$_[0] =~ /::/
700	or Carp::croak "spawn init function must be a fully-qualified name, caught";	664	or Carp::croak "spawn init function must be a fully-qualified name, caught";
701		665
702	($NODE{$noderef} \|\| add_node $noderef)	666	snd_to_func $noderef, "AnyEvent::MP::_spawn" => $id, @_;
703	->send (["", "AnyEvent::MP::_spawn" => $id, @_]);
704		667
705	"$noderef#$id"	668	"$noderef#$id"
706	}	669	}
707		670
708	=back	671	=item after $timeout, @msg
709		672
710	=head1 NODE MESSAGES	673	=item after $timeout, $callback
711		674
712	Nodes understand the following messages sent to them. Many of them take	675	Either sends the given message, or call the given callback, after the
713	arguments called C<@reply>, which will simply be used to compose a reply	676	specified number of seconds.
714	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and
715	the remaining arguments are simply the message data.
716		677
717	While other messages exist, they are not public and subject to change.	678	This is simply a utility function that come sin handy at times.
718		679
719	=over 4
720
721	=cut	680	=cut
722		681
723	=item lookup => $name, @reply	682	sub after($@) {
		683	my ($timeout, @action) = @_;
724		684
725	Replies with the port ID of the specified well-known port, or C<undef>.	685	my $t; $t = AE::timer $timeout, 0, sub {
726		686	undef $t;
727	=item devnull => ...	687	ref $action[0]
728		688	? $action[0]()
729	Generic data sink/CPU heat conversion.	689	: snd @action;
730		690	};
731	=item relay => $port, @msg	691	}
732
733	Simply forwards the message to the given port.
734
735	=item eval => $string[ @reply]
736
737	Evaluates the given string. If C<@reply> is given, then a message of the
738	form C<@reply, $@, @evalres> is sent.
739
740	Example: crash another node.
741
742	snd $othernode, eval => "exit";
743
744	=item time => @reply
745
746	Replies the the current node time to C<@reply>.
747
748	Example: tell the current node to send the current time to C<$myport> in a
749	C<timereply> message.
750
751	snd $NODE, time => $myport, timereply => 1, 2;
752	# => snd $myport, timereply => 1, 2, <time>
753		692
754	=back	693	=back
755		694
756	=head1 AnyEvent::MP vs. Distributed Erlang	695	=head1 AnyEvent::MP vs. Distributed Erlang
757		696
…		…
776	convenience functionality.	715	convenience functionality.
777		716
778	This means that AEMP requires a less tightly controlled environment at the	717	This means that AEMP requires a less tightly controlled environment at the
779	cost of longer node references and a slightly higher management overhead.	718	cost of longer node references and a slightly higher management overhead.
780		719
		720	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		721	uses "local ports are like remote ports".
		722
		723	The failure modes for local ports are quite different (runtime errors
		724	only) then for remote ports - when a local port dies, you I<know> it dies,
		725	when a connection to another node dies, you know nothing about the other
		726	port.
		727
		728	Erlang pretends remote ports are as reliable as local ports, even when
		729	they are not.
		730
		731	AEMP encourages a "treat remote ports differently" philosophy, with local
		732	ports being the special case/exception, where transport errors cannot
		733	occur.
		734
781	=item * Erlang uses processes and a mailbox, AEMP does not queue.	735	=item * Erlang uses processes and a mailbox, AEMP does not queue.
782		736
783	Erlang uses processes that selctively receive messages, and therefore	737	Erlang uses processes that selectively receive messages, and therefore
784	needs a queue. AEMP is event based, queuing messages would serve no useful	738	needs a queue. AEMP is event based, queuing messages would serve no
785	purpose.	739	useful purpose. For the same reason the pattern-matching abilities of
		740	AnyEvent::MP are more limited, as there is little need to be able to
		741	filter messages without dequeing them.
786		742
787	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	743	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
788		744
789	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	745	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
790		746
791	Sending messages in Erlang is synchronous and blocks the process. AEMP	747	Sending messages in Erlang is synchronous and blocks the process (and
792	sends are immediate, connection establishment is handled in the	748	so does not need a queue that can overflow). AEMP sends are immediate,
793	background.	749	connection establishment is handled in the background.
794		750
795	=item * Erlang can silently lose messages, AEMP cannot.	751	=item * Erlang suffers from silent message loss, AEMP does not.
796		752
797	Erlang makes few guarantees on messages delivery - messages can get lost	753	Erlang makes few guarantees on messages delivery - messages can get lost
798	without any of the processes realising it (i.e. you send messages a, b,	754	without any of the processes realising it (i.e. you send messages a, b,
799	and c, and the other side only receives messages a and c).	755	and c, and the other side only receives messages a and c).
800		756
…		…
812	eventually be killed - it cannot happen that a node detects a port as dead	768	eventually be killed - it cannot happen that a node detects a port as dead
813	and then later sends messages to it, finding it is still alive.	769	and then later sends messages to it, finding it is still alive.
814		770
815	=item * Erlang can send messages to the wrong port, AEMP does not.	771	=item * Erlang can send messages to the wrong port, AEMP does not.
816		772
817	In Erlang it is quite possible that a node that restarts reuses a process	773	In Erlang it is quite likely that a node that restarts reuses a process ID
818	ID known to other nodes for a completely different process, causing	774	known to other nodes for a completely different process, causing messages
819	messages destined for that process to end up in an unrelated process.	775	destined for that process to end up in an unrelated process.
820		776
821	AEMP never reuses port IDs, so old messages or old port IDs floating	777	AEMP never reuses port IDs, so old messages or old port IDs floating
822	around in the network will not be sent to an unrelated port.	778	around in the network will not be sent to an unrelated port.
823		779
824	=item * Erlang uses unprotected connections, AEMP uses secure	780	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs. Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC