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

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.102 by root, Tue Oct 6 13:37:52 2009 UTC vs.
Revision 1.124 by root, Sat Mar 3 11:38:43 2012 UTC

…		…
30	rcv $port, pong => sub { warn "pong received\n" };	30	rcv $port, pong => sub { warn "pong received\n" };
31		31
32	# create a port on another node	32	# create a port on another node
33	my $port = spawn $node, $initfunc, @initdata;	33	my $port = spawn $node, $initfunc, @initdata;
34		34
35	# destroy a prot again	35	# destroy a port again
36	kil $port; # "normal" kill	36	kil $port; # "normal" kill
37	kil $port, my_error => "everything is broken"; # error kill	37	kil $port, my_error => "everything is broken"; # error kill
38		38
39	# monitoring	39	# monitoring
40	mon $localport, $cb->(@msg) # callback is invoked on death	40	mon $localport, $cb->(@msg) # callback is invoked on death
…		…
78		78
79	Ports allow you to register C<rcv> handlers that can match all or just	79	Ports allow you to register C<rcv> handlers that can match all or just
80	some messages. Messages send to ports will not be queued, regardless of	80	some messages. Messages send to ports will not be queued, regardless of
81	anything was listening for them or not.	81	anything was listening for them or not.
82		82
		83	Ports are represented by (printable) strings called "port IDs".
		84
83	=item port ID - C<nodeid#portname>	85	=item port ID - C<nodeid#portname>
84		86
85	A port ID is the concatenation of a node ID, a hash-mark (C<#>) as	87	A port ID is the concatenation of a node ID, a hash-mark (C<#>)
86	separator, and a port name (a printable string of unspecified format).	88	as separator, and a port name (a printable string of unspecified
		89	format created by AnyEvent::MP).
87		90
88	=item node	91	=item node
89		92
90	A node is a single process containing at least one port - the node port,	93	A node is a single process containing at least one port - the node port,
91	which enables nodes to manage each other remotely, and to create new	94	which enables nodes to manage each other remotely, and to create new
92	ports.	95	ports.
93		96
94	Nodes are either public (have one or more listening ports) or private	97	Nodes are either public (have one or more listening ports) or private
95	(no listening ports). Private nodes cannot talk to other private nodes	98	(no listening ports). Private nodes cannot talk to other private nodes
96	currently.	99	currently, but all nodes can talk to public nodes.
97		100
		101	Nodes is represented by (printable) strings called "node IDs".
		102
98	=item node ID - C<[A-Z_][a-zA-Z0-9_\-.:]*>	103	=item node ID - C<[A-Za-z0-9_\-.:]*>
99		104
100	A node ID is a string that uniquely identifies the node within a	105	A node ID is a string that uniquely identifies the node within a
101	network. Depending on the configuration used, node IDs can look like a	106	network. Depending on the configuration used, node IDs can look like a
102	hostname, a hostname and a port, or a random string. AnyEvent::MP itself	107	hostname, a hostname and a port, or a random string. AnyEvent::MP itself
103	doesn't interpret node IDs in any way.	108	doesn't interpret node IDs in any way except to uniquely identify a node.
104		109
105	=item binds - C<ip:port>	110	=item binds - C<ip:port>
106		111
107	Nodes can only talk to each other by creating some kind of connection to	112	Nodes can only talk to each other by creating some kind of connection to
108	each other. To do this, nodes should listen on one or more local transport	113	each other. To do this, nodes should listen on one or more local transport
		114	endpoints - binds.
		115
109	endpoints - binds. Currently, only standard C<ip:port> specifications can	116	Currently, only standard C<ip:port> specifications can be used, which
110	be used, which specify TCP ports to listen on.	117	specify TCP ports to listen on. So a bind is basically just a tcp socket
		118	in listening mode thta accepts conenctions form other nodes.
111		119
112	=item seed nodes	120	=item seed nodes
113		121
114	When a node starts, it knows nothing about the network. To teach the node	122	When a node starts, it knows nothing about the network it is in - it
115	about the network it first has to contact some other node within the	123	needs to connect to at least one other node that is already in the
116	network. This node is called a seed.	124	network. These other nodes are called "seed nodes".
117		125
118	Apart from the fact that other nodes know them as seed nodes and they have	126	Seed nodes themselves are not special - they are seed nodes only because
119	to have fixed listening addresses, seed nodes are perfectly normal nodes -	127	some other node I<uses> them as such, but any node can be used as seed
120	any node can function as a seed node for others.	128	node for other nodes, and eahc node cna use a different set of seed nodes.
121		129
122	In addition to discovering the network, seed nodes are also used to	130	In addition to discovering the network, seed nodes are also used to
123	maintain the network and to connect nodes that otherwise would have	131	maintain the network - all nodes using the same seed node form are part of
124	trouble connecting. They form the backbone of an AnyEvent::MP network.	132	the same network. If a network is split into multiple subnets because e.g.
		133	the network link between the parts goes down, then using the same seed
		134	nodes for all nodes ensures that eventually the subnets get merged again.
125		135
126	Seed nodes are expected to be long-running, and at least one seed node	136	Seed nodes are expected to be long-running, and at least one seed node
127	should always be available. They should also be relatively responsive - a	137	should always be available. They should also be relatively responsive - a
128	seed node that blocks for long periods will slow down everybody else.	138	seed node that blocks for long periods will slow down everybody else.
129		139
		140	For small networks, it's best if every node uses the same set of seed
		141	nodes. For large networks, it can be useful to specify "regional" seed
		142	nodes for most nodes in an area, and use all seed nodes as seed nodes for
		143	each other. What's important is that all seed nodes connections form a
		144	complete graph, so that the network cannot split into separate subnets
		145	forever.
		146
		147	Seed nodes are represented by seed IDs.
		148
130	=item seeds - C<host:port>	149	=item seed IDs - C<host:port>
131		150
132	Seeds are transport endpoint(s) (usually a hostname/IP address and a	151	Seed IDs are transport endpoint(s) (usually a hostname/IP address and a
133	TCP port) of nodes that should be used as seed nodes.	152	TCP port) of nodes that should be used as seed nodes.
134		153
135	The nodes listening on those endpoints are expected to be long-running,	154	=item global nodes
136	and at least one of those should always be available. When nodes run out	155
137	of connections (e.g. due to a network error), they try to re-establish	156	An AEMP network needs a discovery service - nodes need to know how to
138	connections to some seednodes again to join the network.	157	connect to other nodes they only know by name. In addition, AEMP offers a
		158	distributed "group database", which maps group names to a list of strings
		159	- for example, to register worker ports.
		160
		161	A network needs at least one global node to work, and allows every node to
		162	be a global node.
		163
		164	Any node that loads the L<AnyEvent::MP::Global> module becomes a global
		165	node and tries to keep connections to all other nodes. So while it can
		166	make sense to make every node "global" in small networks, it usually makes
		167	sense to only make seed nodes into global nodes in large networks (nodes
		168	keep connections to seed nodes and global nodes, so makign them the same
		169	reduces overhead).
139		170
140	=back	171	=back
141		172
142	=head1 VARIABLES/FUNCTIONS	173	=head1 VARIABLES/FUNCTIONS
143		174
…		…
145		176
146	=cut	177	=cut
147		178
148	package AnyEvent::MP;	179	package AnyEvent::MP;
149		180
		181	use AnyEvent::MP::Config ();
150	use AnyEvent::MP::Kernel;	182	use AnyEvent::MP::Kernel;
		183	use AnyEvent::MP::Kernel qw(%NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID);
151		184
152	use common::sense;	185	use common::sense;
153		186
154	use Carp ();	187	use Carp ();
155		188
156	use AE ();	189	use AE ();
		190	use Guard ();
157		191
158	use base "Exporter";	192	use base "Exporter";
159		193
160	our $VERSION = 1.21;	194	our $VERSION = $AnyEvent::MP::Config::VERSION;
161		195
162	our @EXPORT = qw(	196	our @EXPORT = qw(
163	NODE $NODE *SELF node_of after	197	NODE $NODE *SELF node_of after
164	configure	198	configure
165	snd rcv mon mon_guard kil psub peval spawn cal	199	snd rcv mon mon_guard kil psub peval spawn cal
166	port	200	port
		201	db_set db_del db_reg
167	);	202	);
168		203
169	our $SELF;	204	our $SELF;
170		205
171	sub _self_die() {	206	sub _self_die() {
…		…
194	some other nodes in the network to discover other nodes.	229	some other nodes in the network to discover other nodes.
195		230
196	This function configures a node - it must be called exactly once (or	231	This function configures a node - it must be called exactly once (or
197	never) before calling other AnyEvent::MP functions.	232	never) before calling other AnyEvent::MP functions.
198		233
		234	The key/value pairs are basically the same ones as documented for the
		235	F<aemp> command line utility (sans the set/del prefix), with two additions:
		236
		237	=over 4
		238
		239	=item norc => $boolean (default false)
		240
		241	If true, then the rc file (e.g. F<~/.perl-anyevent-mp>) will I<not>
		242	be consulted - all configuraiton options must be specified in the
		243	C<configure> call.
		244
		245	=item force => $boolean (default false)
		246
		247	IF true, then the values specified in the C<configure> will take
		248	precedence over any values configured via the rc file. The default is for
		249	the rc file to override any options specified in the program.
		250
		251	=back
		252
199	=over 4	253	=over 4
200		254
201	=item step 1, gathering configuration from profiles	255	=item step 1, gathering configuration from profiles
202		256
203	The function first looks up a profile in the aemp configuration (see the	257	The function first looks up a profile in the aemp configuration (see the
…		…
216	That means that the values specified in the profile have highest priority	270	That means that the values specified in the profile have highest priority
217	and the values specified directly via C<configure> have lowest priority,	271	and the values specified directly via C<configure> have lowest priority,
218	and can only be used to specify defaults.	272	and can only be used to specify defaults.
219		273
220	If the profile specifies a node ID, then this will become the node ID of	274	If the profile specifies a node ID, then this will become the node ID of
221	this process. If not, then the profile name will be used as node ID. The	275	this process. If not, then the profile name will be used as node ID, with
222	special node ID of C<anon/> will be replaced by a random node ID.	276	a slash (C</>) attached.
		277
		278	If the node ID (or profile name) ends with a slash (C</>), then a random
		279	string is appended to make it unique.
223		280
224	=item step 2, bind listener sockets	281	=item step 2, bind listener sockets
225		282
226	The next step is to look up the binds in the profile, followed by binding	283	The next step is to look up the binds in the profile, followed by binding
227	aemp protocol listeners on all binds specified (it is possible and valid	284	aemp protocol listeners on all binds specified (it is possible and valid
…		…
233	used, meaning the node will bind on a dynamically-assigned port on every	290	used, meaning the node will bind on a dynamically-assigned port on every
234	local IP address it finds.	291	local IP address it finds.
235		292
236	=item step 3, connect to seed nodes	293	=item step 3, connect to seed nodes
237		294
238	As the last step, the seeds list from the profile is passed to the	295	As the last step, the seed ID list from the profile is passed to the
239	L<AnyEvent::MP::Global> module, which will then use it to keep	296	L<AnyEvent::MP::Global> module, which will then use it to keep
240	connectivity with at least one node at any point in time.	297	connectivity with at least one node at any point in time.
241		298
242	=back	299	=back
243		300
…		…
249	Example: become an anonymous node. This form is often used for commandline	306	Example: become an anonymous node. This form is often used for commandline
250	clients.	307	clients.
251		308
252	configure nodeid => "anon/";	309	configure nodeid => "anon/";
253		310
254	Example: configure a node using a profile called seed, which si suitable	311	Example: configure a node using a profile called seed, which is suitable
255	for a seed node as it binds on all local addresses on a fixed port (4040,	312	for a seed node as it binds on all local addresses on a fixed port (4040,
256	customary for aemp).	313	customary for aemp).
257		314
258	# use the aemp commandline utility	315	# use the aemp commandline utility
259	# aemp profile seed nodeid anon/ binds '*:4040'	316	# aemp profile seed binds '*:4040'
260		317
261	# then use it	318	# then use it
262	configure profile => "seed";	319	configure profile => "seed";
263		320
264	# or simply use aemp from the shell again:	321	# or simply use aemp from the shell again:
…		…
334	sub _kilme {	391	sub _kilme {
335	die "received message on port without callback";	392	die "received message on port without callback";
336	}	393	}
337		394
338	sub port(;&) {	395	sub port(;&) {
339	my $id = "$UNIQ." . $ID++;	396	my $id = $UNIQ . ++$ID;
340	my $port = "$NODE#$id";	397	my $port = "$NODE#$id";
341		398
342	rcv $port, shift \|\| \&_kilme;	399	rcv $port, shift \|\| \&_kilme;
343		400
344	$port	401	$port
…		…
406	if (ref $_[0]) {	463	if (ref $_[0]) {
407	if (my $self = $PORT_DATA{$portid}) {	464	if (my $self = $PORT_DATA{$portid}) {
408	"AnyEvent::MP::Port" eq ref $self	465	"AnyEvent::MP::Port" eq ref $self
409	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	466	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
410		467
411	$self->[2] = shift;	468	$self->[0] = shift;
412	} else {	469	} else {
413	my $cb = shift;	470	my $cb = shift;
414	$PORT{$portid} = sub {	471	$PORT{$portid} = sub {
415	local $SELF = $port;	472	local $SELF = $port;
416	eval { &$cb }; _self_die if $@;	473	eval { &$cb }; _self_die if $@;
417	};	474	};
418	}	475	}
419	} elsif (defined $_[0]) {	476	} elsif (defined $_[0]) {
420	my $self = $PORT_DATA{$portid} \|\|= do {	477	my $self = $PORT_DATA{$portid} \|\|= do {
421	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";	478	my $self = bless [$PORT{$portid} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
422		479
423	$PORT{$portid} = sub {	480	$PORT{$portid} = sub {
424	local $SELF = $port;	481	local $SELF = $port;
425		482
426	if (my $cb = $self->[1]{$_[0]}) {	483	if (my $cb = $self->[1]{$_[0]}) {
…		…
492	Remembers C<$SELF> and creates a closure out of the BLOCK. When the	549	Remembers C<$SELF> and creates a closure out of the BLOCK. When the
493	closure is executed, sets up the environment in the same way as in C<rcv>	550	closure is executed, sets up the environment in the same way as in C<rcv>
494	callbacks, i.e. runtime errors will cause the port to get C<kil>ed.	551	callbacks, i.e. runtime errors will cause the port to get C<kil>ed.
495		552
496	The effect is basically as if it returned C<< sub { peval $SELF, sub {	553	The effect is basically as if it returned C<< sub { peval $SELF, sub {
497	BLOCK } } >>.	554	BLOCK }, @_ } >>.
498		555
499	This is useful when you register callbacks from C<rcv> callbacks:	556	This is useful when you register callbacks from C<rcv> callbacks:
500		557
501	rcv delayed_reply => sub {	558	rcv delayed_reply => sub {
502	my ($delay, @reply) = @_;	559	my ($delay, @reply) = @_;
…		…
617	}	674	}
618		675
619	$node->monitor ($port, $cb);	676	$node->monitor ($port, $cb);
620		677
621	defined wantarray	678	defined wantarray
622	and ($cb += 0, AnyEvent::Util::guard { $node->unmonitor ($port, $cb) })	679	and ($cb += 0, Guard::guard { $node->unmonitor ($port, $cb) })
623	}	680	}
624		681
625	=item $guard = mon_guard $port, $ref, $ref...	682	=item $guard = mon_guard $port, $ref, $ref...
626		683
627	Monitors the given C<$port> and keeps the passed references. When the port	684	Monitors the given C<$port> and keeps the passed references. When the port
…		…
650		707
651	=item kil $port[, @reason]	708	=item kil $port[, @reason]
652		709
653	Kill the specified port with the given C<@reason>.	710	Kill the specified port with the given C<@reason>.
654		711
655	If no C<@reason> is specified, then the port is killed "normally" (ports	712	If no C<@reason> is specified, then the port is killed "normally" -
656	monitoring other ports will not necessarily die because a port dies	713	monitor callback will be invoked, but the kil will not cause linked ports
657	"normally").	714	(C<mon $mport, $lport> form) to get killed.
658		715
659	Otherwise, linked ports get killed with the same reason (second form of	716	If a C<@reason> is specified, then linked ports (C<mon $mport, $lport>
660	C<mon>, see above).	717	form) get killed with the same reason.
661		718
662	Runtime errors while evaluating C<rcv> callbacks or inside C<psub> blocks	719	Runtime errors while evaluating C<rcv> callbacks or inside C<psub> blocks
663	will be reported as reason C<< die => $@ >>.	720	will be reported as reason C<< die => $@ >>.
664		721
665	Transport/communication errors are reported as C<< transport_error =>	722	Transport/communication errors are reported as C<< transport_error =>
…		…
731	}	788	}
732		789
733	sub spawn(@) {	790	sub spawn(@) {
734	my ($nodeid, undef) = split /#/, shift, 2;	791	my ($nodeid, undef) = split /#/, shift, 2;
735		792
736	my $id = "$RUNIQ." . $ID++;	793	my $id = $RUNIQ . ++$ID;
737		794
738	$_[0] =~ /::/	795	$_[0] =~ /::/
739	or Carp::croak "spawn init function must be a fully-qualified name, caught";	796	or Carp::croak "spawn init function must be a fully-qualified name, caught";
740		797
741	snd_to_func $nodeid, "AnyEvent::MP::_spawn" => $id, @_;	798	snd_to_func $nodeid, "AnyEvent::MP::_spawn" => $id, @_;
742		799
743	"$nodeid#$id"	800	"$nodeid#$id"
744	}	801	}
		802
745		803
746	=item after $timeout, @msg	804	=item after $timeout, @msg
747		805
748	=item after $timeout, $callback	806	=item after $timeout, $callback
749		807
…		…
819	$port	877	$port
820	}	878	}
821		879
822	=back	880	=back
823		881
		882	=head1 DISTRIBUTED DATABASE
		883
		884	AnyEvent::MP comes with a simple distributed database. The database will
		885	be mirrored asynchronously at all global nodes. Other nodes bind to one of
		886	the global nodes for their needs.
		887
		888	The database consists of a two-level hash - a hash contains a hash which
		889	contains values.
		890
		891	The top level hash key is called "family", and the second-level hash key
		892	is simply called "key".
		893
		894	The family and key must be alphanumeric ASCII strings, i.e. start
		895	with a letter and consist of letters, digits, underscores and colons
		896	(C<[A-Za-z][A-Za-z0-9_:]*>, pretty much like Perl module names.
		897
		898	As the family namespaceis global, it is recommended to prefix family names
		899	with the name of the application or module using it.
		900
		901	The values should preferably be strings, but other perl scalars should
		902	work as well (such as arrays and hashes).
		903
		904	Every database entry is owned by one node - adding the same family/key
		905	combination on multiple nodes will not cause discomfort for AnyEvent::MP,
		906	but the result might be nondeterministic, i.e. the key might have
		907	different values on different nodes.
		908
		909	=item db_set $family => $key => $value
		910
		911	Sets (or replaces) a key to the database.
		912
		913	=item db_del $family => $key
		914
		915	Deletes a key from the database.
		916
		917	=item $guard = db_reg $family => $key [=> $value]
		918
		919	Sets the key on the database and returns a guard. When the guard is
		920	destroyed, the key is deleted from the database. If C<$value> is missing,
		921	then C<undef> is used.
		922
		923	=cut
		924
		925	=back
		926
824	=head1 AnyEvent::MP vs. Distributed Erlang	927	=head1 AnyEvent::MP vs. Distributed Erlang
825		928
826	AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node	929	AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node
827	== aemp node, Erlang process == aemp port), so many of the documents and	930	== aemp node, Erlang process == aemp port), so many of the documents and
828	programming techniques employed by Erlang apply to AnyEvent::MP. Here is a	931	programming techniques employed by Erlang apply to AnyEvent::MP. Here is a
…		…
859	ports being the special case/exception, where transport errors cannot	962	ports being the special case/exception, where transport errors cannot
860	occur.	963	occur.
861		964
862	=item * Erlang uses processes and a mailbox, AEMP does not queue.	965	=item * Erlang uses processes and a mailbox, AEMP does not queue.
863		966
864	Erlang uses processes that selectively receive messages, and therefore	967	Erlang uses processes that selectively receive messages out of order, and
865	needs a queue. AEMP is event based, queuing messages would serve no	968	therefore needs a queue. AEMP is event based, queuing messages would serve
866	useful purpose. For the same reason the pattern-matching abilities of	969	no useful purpose. For the same reason the pattern-matching abilities
867	AnyEvent::MP are more limited, as there is little need to be able to	970	of AnyEvent::MP are more limited, as there is little need to be able to
868	filter messages without dequeuing them.	971	filter messages without dequeuing them.
869		972
870	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	973	This is not a philosophical difference, but simply stems from AnyEvent::MP
		974	being event-based, while Erlang is process-based.
		975
		976	You cna have a look at L<Coro::MP> for a more Erlang-like process model on
		977	top of AEMP and Coro threads.
871		978
872	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	979	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
873		980
874	Sending messages in Erlang is synchronous and blocks the process (and	981	Sending messages in Erlang is synchronous and blocks the process until
		982	a conenction has been established and the message sent (and so does not
875	so does not need a queue that can overflow). AEMP sends are immediate,	983	need a queue that can overflow). AEMP sends return immediately, connection
876	connection establishment is handled in the background.	984	establishment is handled in the background.
877		985
878	=item * Erlang suffers from silent message loss, AEMP does not.	986	=item * Erlang suffers from silent message loss, AEMP does not.
879		987
880	Erlang implements few guarantees on messages delivery - messages can get	988	Erlang implements few guarantees on messages delivery - messages can get
881	lost without any of the processes realising it (i.e. you send messages a,	989	lost without any of the processes realising it (i.e. you send messages a,
882	b, and c, and the other side only receives messages a and c).	990	b, and c, and the other side only receives messages a and c).
883		991
884	AEMP guarantees correct ordering, and the guarantee that after one message	992	AEMP guarantees (modulo hardware errors) correct ordering, and the
885	is lost, all following ones sent to the same port are lost as well, until	993	guarantee that after one message is lost, all following ones sent to the
886	monitoring raises an error, so there are no silent "holes" in the message	994	same port are lost as well, until monitoring raises an error, so there are
887	sequence.	995	no silent "holes" in the message sequence.
		996
		997	If you want your software to be very reliable, you have to cope with
		998	corrupted and even out-of-order messages in both Erlang and AEMP. AEMP
		999	simply tries to work better in common error cases, such as when a network
		1000	link goes down.
888		1001
889	=item * Erlang can send messages to the wrong port, AEMP does not.	1002	=item * Erlang can send messages to the wrong port, AEMP does not.
890		1003
891	In Erlang it is quite likely that a node that restarts reuses a process ID	1004	In Erlang it is quite likely that a node that restarts reuses an Erlang
892	known to other nodes for a completely different process, causing messages	1005	process ID known to other nodes for a completely different process,
893	destined for that process to end up in an unrelated process.	1006	causing messages destined for that process to end up in an unrelated
		1007	process.
894		1008
895	AEMP never reuses port IDs, so old messages or old port IDs floating	1009	AEMP does not reuse port IDs, so old messages or old port IDs floating
896	around in the network will not be sent to an unrelated port.	1010	around in the network will not be sent to an unrelated port.
897		1011
898	=item * Erlang uses unprotected connections, AEMP uses secure	1012	=item * Erlang uses unprotected connections, AEMP uses secure
899	authentication and can use TLS.	1013	authentication and can use TLS.
900		1014
…		…
903		1017
904	=item * The AEMP protocol is optimised for both text-based and binary	1018	=item * The AEMP protocol is optimised for both text-based and binary
905	communications.	1019	communications.
906		1020
907	The AEMP protocol, unlike the Erlang protocol, supports both programming	1021	The AEMP protocol, unlike the Erlang protocol, supports both programming
908	language independent text-only protocols (good for debugging) and binary,	1022	language independent text-only protocols (good for debugging), and binary,
909	language-specific serialisers (e.g. Storable). By default, unless TLS is	1023	language-specific serialisers (e.g. Storable). By default, unless TLS is
910	used, the protocol is actually completely text-based.	1024	used, the protocol is actually completely text-based.
911		1025
912	It has also been carefully designed to be implementable in other languages	1026	It has also been carefully designed to be implementable in other languages
913	with a minimum of work while gracefully degrading functionality to make the	1027	with a minimum of work while gracefully degrading functionality to make the
914	protocol simple.	1028	protocol simple.
915		1029
916	=item * AEMP has more flexible monitoring options than Erlang.	1030	=item * AEMP has more flexible monitoring options than Erlang.
917		1031
918	In Erlang, you can chose to receive I<all> exit signals as messages	1032	In Erlang, you can chose to receive I<all> exit signals as messages or
919	or I<none>, there is no in-between, so monitoring single processes is	1033	I<none>, there is no in-between, so monitoring single Erlang processes is
920	difficult to implement. Monitoring in AEMP is more flexible than in	1034	difficult to implement.
921	Erlang, as one can choose between automatic kill, exit message or callback	1035
922	on a per-process basis.	1036	Monitoring in AEMP is more flexible than in Erlang, as one can choose
		1037	between automatic kill, exit message or callback on a per-port basis.
923		1038
924	=item * Erlang tries to hide remote/local connections, AEMP does not.	1039	=item * Erlang tries to hide remote/local connections, AEMP does not.
925		1040
926	Monitoring in Erlang is not an indicator of process death/crashes, in the	1041	Monitoring in Erlang is not an indicator of process death/crashes, in the
927	same way as linking is (except linking is unreliable in Erlang).	1042	same way as linking is (except linking is unreliable in Erlang).
…		…
949	overhead, as well as having to keep a proxy object everywhere.	1064	overhead, as well as having to keep a proxy object everywhere.
950		1065
951	Strings can easily be printed, easily serialised etc. and need no special	1066	Strings can easily be printed, easily serialised etc. and need no special
952	procedures to be "valid".	1067	procedures to be "valid".
953		1068
954	And as a result, a miniport consists of a single closure stored in a	1069	And as a result, a port with just a default receiver consists of a single
955	global hash - it can't become much cheaper.	1070	code reference stored in a global hash - it can't become much cheaper.
956		1071
957	=item Why favour JSON, why not a real serialising format such as Storable?	1072	=item Why favour JSON, why not a real serialising format such as Storable?
958		1073
959	In fact, any AnyEvent::MP node will happily accept Storable as framing	1074	In fact, any AnyEvent::MP node will happily accept Storable as framing
960	format, but currently there is no way to make a node use Storable by	1075	format, but currently there is no way to make a node use Storable by
…		…
976		1091
977	L<AnyEvent::MP::Intro> - a gentle introduction.	1092	L<AnyEvent::MP::Intro> - a gentle introduction.
978		1093
979	L<AnyEvent::MP::Kernel> - more, lower-level, stuff.	1094	L<AnyEvent::MP::Kernel> - more, lower-level, stuff.
980		1095
981	L<AnyEvent::MP::Global> - network maintainance and port groups, to find	1096	L<AnyEvent::MP::Global> - network maintenance and port groups, to find
982	your applications.	1097	your applications.
		1098
		1099	L<AnyEvent::MP::DataConn> - establish data connections between nodes.
983		1100
984	L<AnyEvent::MP::LogCatcher> - simple service to display log messages from	1101	L<AnyEvent::MP::LogCatcher> - simple service to display log messages from
985	all nodes.	1102	all nodes.
986		1103
987	L<AnyEvent>.	1104	L<AnyEvent>.

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.102 by root, Tue Oct 6 13:37:52 2009 UTC vs. Revision 1.124 by root, Sat Mar 3 11:38:43 2012 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.102 by root, Tue Oct 6 13:37:52 2009 UTC vs.
Revision 1.124 by root, Sat Mar 3 11:38:43 2012 UTC