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

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.122 by root, Wed Feb 29 18:44:59 2012 UTC vs.
Revision 1.139 by root, Thu Mar 22 20:07:31 2012 UTC

…		…
35	# destroy a port 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 $port, $cb->(@msg) # callback is invoked on death
41	mon $localport, $otherport # kill otherport on abnormal death	41	mon $port, $localport # kill localport on abnormal death
42	mon $localport, $otherport, @msg # send message on death	42	mon $port, $localport, @msg # send message on death
43		43
44	# temporarily execute code in port context	44	# temporarily execute code in port context
45	peval $port, sub { die "kill the port!" };	45	peval $port, sub { die "kill the port!" };
46		46
47	# execute callbacks in $SELF port context	47	# execute callbacks in $SELF port context
…		…
82		82
83	Ports are represented by (printable) strings called "port IDs".	83	Ports are represented by (printable) strings called "port IDs".
84		84
85	=item port ID - C<nodeid#portname>	85	=item port ID - C<nodeid#portname>
86		86
87	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<#>)
88	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).
89		90
90	=item node	91	=item node
91		92
92	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,
93	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
…		…
184	use common::sense;	185	use common::sense;
185		186
186	use Carp ();	187	use Carp ();
187		188
188	use AE ();	189	use AE ();
		190	use Guard ();
189		191
190	use base "Exporter";	192	use base "Exporter";
191		193
192	our $VERSION = $AnyEvent::MP::Config::VERSION;	194	our $VERSION = $AnyEvent::MP::Config::VERSION;
193		195
194	our @EXPORT = qw(	196	our @EXPORT = qw(
195	NODE $NODE *SELF node_of after	197	NODE $NODE *SELF node_of after
196	configure	198	configure
197	snd rcv mon mon_guard kil psub peval spawn cal	199	snd rcv mon mon_guard kil psub peval spawn cal
198	port	200	port
		201	db_set db_del db_reg
		202	db_mon db_family db_keys db_values
199	);	203	);
200		204
201	our $SELF;	205	our $SELF;
202		206
203	sub _self_die() {	207	sub _self_die() {
…		…
227		231
228	This function configures a node - it must be called exactly once (or	232	This function configures a node - it must be called exactly once (or
229	never) before calling other AnyEvent::MP functions.	233	never) before calling other AnyEvent::MP functions.
230		234
231	The key/value pairs are basically the same ones as documented for the	235	The key/value pairs are basically the same ones as documented for the
232	F<aemp> command line utility (sans the set/del prefix), with two additions:	236	F<aemp> command line utility (sans the set/del prefix), with these additions:
233		237
234	=over 4	238	=over 4
235		239
236	=item norc => $boolean (default false)	240	=item norc => $boolean (default false)
237		241
…		…
242	=item force => $boolean (default false)	246	=item force => $boolean (default false)
243		247
244	IF true, then the values specified in the C<configure> will take	248	IF true, then the values specified in the C<configure> will take
245	precedence over any values configured via the rc file. The default is for	249	precedence over any values configured via the rc file. The default is for
246	the rc file to override any options specified in the program.	250	the rc file to override any options specified in the program.
		251
		252	=item secure => $pass->(@msg)
		253
		254	In addition to specifying a boolean, you can specify a code reference that
		255	is called for every code execution attempt - the execution request is
		256	granted iff the callback returns a true value.
		257
		258	Most of the time the callback should look only at
		259	C<$AnyEvent::MP::Kernel::SRCNODE> to make a decision, and not at the
		260	actual message (which can be about anything, and is mostly provided for
		261	diagnostic purposes).
		262
		263	See F<semp setsecure> for more info.
247		264
248	=back	265	=back
249		266
250	=over 4	267	=over 4
251		268
…		…
268	and the values specified directly via C<configure> have lowest priority,	285	and the values specified directly via C<configure> have lowest priority,
269	and can only be used to specify defaults.	286	and can only be used to specify defaults.
270		287
271	If the profile specifies a node ID, then this will become the node ID of	288	If the profile specifies a node ID, then this will become the node ID of
272	this process. If not, then the profile name will be used as node ID, with	289	this process. If not, then the profile name will be used as node ID, with
273	a slash (C</>) attached.	290	a unique randoms tring (C</%u>) appended.
274		291
275	If the node ID (or profile name) ends with a slash (C</>), then a random	292	The node ID can contain some C<%> sequences that are expanded: C<%n>
276	string is appended to make it unique.	293	is expanded to the local nodename, C<%u> is replaced by a random
		294	strign to make the node unique. For example, the F<aemp> commandline
		295	utility uses C<aemp/%n/%u> as nodename, which might expand to
		296	C<aemp/cerebro/ZQDGSIkRhEZQDGSIkRhE>.
277		297
278	=item step 2, bind listener sockets	298	=item step 2, bind listener sockets
279		299
280	The next step is to look up the binds in the profile, followed by binding	300	The next step is to look up the binds in the profile, followed by binding
281	aemp protocol listeners on all binds specified (it is possible and valid	301	aemp protocol listeners on all binds specified (it is possible and valid
…		…
298	Example: become a distributed node using the local node name as profile.	318	Example: become a distributed node using the local node name as profile.
299	This should be the most common form of invocation for "daemon"-type nodes.	319	This should be the most common form of invocation for "daemon"-type nodes.
300		320
301	configure	321	configure
302		322
303	Example: become an anonymous node. This form is often used for commandline	323	Example: become a semi-anonymous node. This form is often used for
304	clients.	324	commandline clients.
305		325
306	configure nodeid => "anon/";	326	configure nodeid => "myscript/%n/%u";
307		327
308	Example: configure a node using a profile called seed, which is suitable	328	Example: configure a node using a profile called seed, which is suitable
309	for a seed node as it binds on all local addresses on a fixed port (4040,	329	for a seed node as it binds on all local addresses on a fixed port (4040,
310	customary for aemp).	330	customary for aemp).
311		331
…		…
383		403
384	=cut	404	=cut
385		405
386	sub rcv($@);	406	sub rcv($@);
387		407
388	sub _kilme {	408	my $KILME = sub {
389	die "received message on port without callback";	409	(my $tag = substr $_[0], 0, 30) =~ s/([\x20-\x7e])/./g;
390	}	410	kil $SELF, unhandled_message => "no callback found for message '$tag'";
		411	};
391		412
392	sub port(;&) {	413	sub port(;&) {
393	my $id = "$UNIQ." . ++$ID;	414	my $id = $UNIQ . ++$ID;
394	my $port = "$NODE#$id";	415	my $port = "$NODE#$id";
395		416
396	rcv $port, shift \|\| \&_kilme;	417	rcv $port, shift \|\| $KILME;
397		418
398	$port	419	$port
399	}	420	}
400		421
401	=item rcv $local_port, $callback->(@msg)	422	=item rcv $local_port, $callback->(@msg)
…		…
406		427
407	The global C<$SELF> (exported by this module) contains C<$port> while	428	The global C<$SELF> (exported by this module) contains C<$port> while
408	executing the callback. Runtime errors during callback execution will	429	executing the callback. Runtime errors during callback execution will
409	result in the port being C<kil>ed.	430	result in the port being C<kil>ed.
410		431
411	The default callback received all messages not matched by a more specific	432	The default callback receives all messages not matched by a more specific
412	C<tag> match.	433	C<tag> match.
413		434
414	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...	435	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
415		436
416	Register (or replace) callbacks to be called on messages starting with the	437	Register (or replace) callbacks to be called on messages starting with the
…		…
580	$res	601	$res
581	}	602	}
582	}	603	}
583	}	604	}
584		605
		606	=item $guard = mon $port, $rcvport # kill $rcvport when $port dies
		607
		608	=item $guard = mon $port # kill $SELF when $port dies
		609
585	=item $guard = mon $port, $cb->(@reason) # call $cb when $port dies	610	=item $guard = mon $port, $cb->(@reason) # call $cb when $port dies
586
587	=item $guard = mon $port, $rcvport # kill $rcvport when $port dies
588
589	=item $guard = mon $port # kill $SELF when $port dies
590		611
591	=item $guard = mon $port, $rcvport, @msg # send a message when $port dies	612	=item $guard = mon $port, $rcvport, @msg # send a message when $port dies
592		613
593	Monitor the given port and do something when the port is killed or	614	Monitor the given port and do something when the port is killed or
594	messages to it were lost, and optionally return a guard that can be used	615	messages to it were lost, and optionally return a guard that can be used
595	to stop monitoring again.	616	to stop monitoring again.
596		617
		618	The first two forms distinguish between "normal" and "abnormal" kil's:
		619
		620	In the first form (another port given), if the C<$port> is C<kil>'ed with
		621	a non-empty reason, the other port (C<$rcvport>) will be kil'ed with the
		622	same reason. That is, on "normal" kil's nothing happens, while under all
		623	other conditions, the other port is killed with the same reason.
		624
		625	The second form (kill self) is the same as the first form, except that
		626	C<$rvport> defaults to C<$SELF>.
		627
		628	The remaining forms don't distinguish between "normal" and "abnormal" kil's
		629	- it's up to the callback or receiver to check whether the C<@reason> is
		630	empty and act accordingly.
		631
597	In the first form (callback), the callback is simply called with any	632	In the third form (callback), the callback is simply called with any
598	number of C<@reason> elements (no @reason means that the port was deleted	633	number of C<@reason> elements (empty @reason means that the port was deleted
599	"normally"). Note also that I<< the callback B<must> never die >>, so use	634	"normally"). Note also that I<< the callback B<must> never die >>, so use
600	C<eval> if unsure.	635	C<eval> if unsure.
601		636
602	In the second form (another port given), the other port (C<$rcvport>)
603	will be C<kil>'ed with C<@reason>, if a @reason was specified, i.e. on
604	"normal" kils nothing happens, while under all other conditions, the other
605	port is killed with the same reason.
606
607	The third form (kill self) is the same as the second form, except that
608	C<$rvport> defaults to C<$SELF>.
609
610	In the last form (message), a message of the form C<@msg, @reason> will be	637	In the last form (message), a message of the form C<$rcvport, @msg,
611	C<snd>.	638	@reason> will be C<snd>.
612		639
613	Monitoring-actions are one-shot: once messages are lost (and a monitoring	640	Monitoring-actions are one-shot: once messages are lost (and a monitoring
614	alert was raised), they are removed and will not trigger again.	641	alert was raised), they are removed and will not trigger again, even if it
		642	turns out that the port is still alive.
615		643
616	As a rule of thumb, monitoring requests should always monitor a port from	644	As a rule of thumb, monitoring requests should always monitor a remote
617	a local port (or callback). The reason is that kill messages might get	645	port locally (using a local C<$rcvport> or a callback). The reason is that
618	lost, just like any other message. Another less obvious reason is that	646	kill messages might get lost, just like any other message. Another less
619	even monitoring requests can get lost (for example, when the connection	647	obvious reason is that even monitoring requests can get lost (for example,
620	to the other node goes down permanently). When monitoring a port locally	648	when the connection to the other node goes down permanently). When
621	these problems do not exist.	649	monitoring a port locally these problems do not exist.
622		650
623	C<mon> effectively guarantees that, in the absence of hardware failures,	651	C<mon> effectively guarantees that, in the absence of hardware failures,
624	after starting the monitor, either all messages sent to the port will	652	after starting the monitor, either all messages sent to the port will
625	arrive, or the monitoring action will be invoked after possible message	653	arrive, or the monitoring action will be invoked after possible message
626	loss has been detected. No messages will be lost "in between" (after	654	loss has been detected. No messages will be lost "in between" (after
…		…
671	}	699	}
672		700
673	$node->monitor ($port, $cb);	701	$node->monitor ($port, $cb);
674		702
675	defined wantarray	703	defined wantarray
676	and ($cb += 0, AnyEvent::Util::guard { $node->unmonitor ($port, $cb) })	704	and ($cb += 0, Guard::guard { $node->unmonitor ($port, $cb) })
677	}	705	}
678		706
679	=item $guard = mon_guard $port, $ref, $ref...	707	=item $guard = mon_guard $port, $ref, $ref...
680		708
681	Monitors the given C<$port> and keeps the passed references. When the port	709	Monitors the given C<$port> and keeps the passed references. When the port
…		…
717	will be reported as reason C<< die => $@ >>.	745	will be reported as reason C<< die => $@ >>.
718		746
719	Transport/communication errors are reported as C<< transport_error =>	747	Transport/communication errors are reported as C<< transport_error =>
720	$message >>.	748	$message >>.
721		749
722	=cut	750	Common idioms:
		751
		752	# silently remove yourself, do not kill linked ports
		753	kil $SELF;
		754
		755	# report a failure in some detail
		756	kil $SELF, failure_mode_1 => "it failed with too high temperature";
		757
		758	# do not waste much time with killing, just die when something goes wrong
		759	open my $fh, "<file"
		760	or die "file: $!";
723		761
724	=item $port = spawn $node, $initfunc[, @initdata]	762	=item $port = spawn $node, $initfunc[, @initdata]
725		763
726	Creates a port on the node C<$node> (which can also be a port ID, in which	764	Creates a port on the node C<$node> (which can also be a port ID, in which
727	case it's the node where that port resides).	765	case it's the node where that port resides).
…		…
785	}	823	}
786		824
787	sub spawn(@) {	825	sub spawn(@) {
788	my ($nodeid, undef) = split /#/, shift, 2;	826	my ($nodeid, undef) = split /#/, shift, 2;
789		827
790	my $id = "$RUNIQ." . ++$ID;	828	my $id = $RUNIQ . ++$ID;
791		829
792	$_[0] =~ /::/	830	$_[0] =~ /::/
793	or Carp::croak "spawn init function must be a fully-qualified name, caught";	831	or Carp::croak "spawn init function must be a fully-qualified name, caught";
794		832
795	snd_to_func $nodeid, "AnyEvent::MP::_spawn" => $id, @_;	833	snd_to_func $nodeid, "AnyEvent::MP::_spawn" => $id, @_;
…		…
819	ref $action[0]	857	ref $action[0]
820	? $action[0]()	858	? $action[0]()
821	: snd @action;	859	: snd @action;
822	};	860	};
823	}	861	}
		862
		863	#=item $cb2 = timeout $seconds, $cb[, @args]
824		864
825	=item cal $port, @msg, $callback[, $timeout]	865	=item cal $port, @msg, $callback[, $timeout]
826		866
827	A simple form of RPC - sends a message to the given C<$port> with the	867	A simple form of RPC - sends a message to the given C<$port> with the
828	given contents (C<@msg>), but adds a reply port to the message.	868	given contents (C<@msg>), but adds a reply port to the message.
…		…
874	$port	914	$port
875	}	915	}
876		916
877	=back	917	=back
878		918
		919	=head1 DISTRIBUTED DATABASE
		920
		921	AnyEvent::MP comes with a simple distributed database. The database will
		922	be mirrored asynchronously on all global nodes. Other nodes bind to one
		923	of the global nodes for their needs. Every node has a "local database"
		924	which contains all the values that are set locally. All local databases
		925	are merged together to form the global database, which can be queried.
		926
		927	The database structure is that of a two-level hash - the database hash
		928	contains hashes which contain values, similarly to a perl hash of hashes,
		929	i.e.:
		930
		931	$DATABASE{$family}{$subkey} = $value
		932
		933	The top level hash key is called "family", and the second-level hash key
		934	is called "subkey" or simply "key".
		935
		936	The family must be alphanumeric, i.e. start with a letter and consist
		937	of letters, digits, underscores and colons (C<[A-Za-z][A-Za-z0-9_:]*>,
		938	pretty much like Perl module names.
		939
		940	As the family namespace is global, it is recommended to prefix family names
		941	with the name of the application or module using it.
		942
		943	The subkeys must be non-empty strings, with no further restrictions.
		944
		945	The values should preferably be strings, but other perl scalars should
		946	work as well (such as C<undef>, arrays and hashes).
		947
		948	Every database entry is owned by one node - adding the same family/subkey
		949	combination on multiple nodes will not cause discomfort for AnyEvent::MP,
		950	but the result might be nondeterministic, i.e. the key might have
		951	different values on different nodes.
		952
		953	Different subkeys in the same family can be owned by different nodes
		954	without problems, and in fact, this is the common method to create worker
		955	pools. For example, a worker port for image scaling might do this:
		956
		957	db_set my_image_scalers => $port;
		958
		959	And clients looking for an image scaler will want to get the
		960	C<my_image_scalers> keys from time to time:
		961
		962	db_keys my_image_scalers => sub {
		963	@ports = @{ $_[0] };
		964	};
		965
		966	Or better yet, they want to monitor the database family, so they always
		967	have a reasonable up-to-date copy:
		968
		969	db_mon my_image_scalers => sub {
		970	@ports = keys %{ $_[0] };
		971	};
		972
		973	In general, you can set or delete single subkeys, but query and monitor
		974	whole families only.
		975
		976	If you feel the need to monitor or query a single subkey, try giving it
		977	it's own family.
		978
		979	=over
		980
		981	=item $guard = db_set $family => $subkey [=> $value]
		982
		983	Sets (or replaces) a key to the database - if C<$value> is omitted,
		984	C<undef> is used instead.
		985
		986	When called in non-void context, C<db_set> returns a guard that
		987	automatically calls C<db_del> when it is destroyed.
		988
		989	=item db_del $family => $subkey...
		990
		991	Deletes one or more subkeys from the database family.
		992
		993	=item $guard = db_reg $family => $port => $value
		994
		995	=item $guard = db_reg $family => $port
		996
		997	=item $guard = db_reg $family
		998
		999	Registers a port in the given family and optionally returns a guard to
		1000	remove it.
		1001
		1002	This function basically does the same as:
		1003
		1004	db_set $family => $port => $value
		1005
		1006	Except that the port is monitored and automatically removed from the
		1007	database family when it is kil'ed.
		1008
		1009	If C<$value> is missing, C<undef> is used. If C<$port> is missing, then
		1010	C<$SELF> is used.
		1011
		1012	This function is most useful to register a port in some port group (which
		1013	is just another name for a database family), and have it removed when the
		1014	port is gone. This works best when the port is a local port.
		1015
		1016	=cut
		1017
		1018	sub db_reg($$;$) {
		1019	my $family = shift;
		1020	my $port = @_ ? shift : $SELF;
		1021
		1022	my $clr = sub { db_del $family => $port };
		1023	mon $port, $clr;
		1024
		1025	db_set $family => $port => $_[0];
		1026
		1027	defined wantarray
		1028	and &Guard::guard ($clr)
		1029	}
		1030
		1031	=item db_family $family => $cb->(\%familyhash)
		1032
		1033	Queries the named database C<$family> and call the callback with the
		1034	family represented as a hash. You can keep and freely modify the hash.
		1035
		1036	=item db_keys $family => $cb->(\@keys)
		1037
		1038	Same as C<db_family>, except it only queries the family I<subkeys> and passes
		1039	them as array reference to the callback.
		1040
		1041	=item db_values $family => $cb->(\@values)
		1042
		1043	Same as C<db_family>, except it only queries the family I<values> and passes them
		1044	as array reference to the callback.
		1045
		1046	=item $guard = db_mon $family => $cb->($familyhash, \@added, \@changed, \@deleted)
		1047
		1048	Creates a monitor on the given database family. Each time a key is set
		1049	or or is deleted the callback is called with a hash containing the
		1050	database family and three lists of added, changed and deleted subkeys,
		1051	respectively. If no keys have changed then the array reference might be
		1052	C<undef> or even missing.
		1053
		1054	If not called in void context, a guard object is returned that, when
		1055	destroyed, stops the monitor.
		1056
		1057	The family hash reference and the key arrays belong to AnyEvent::MP and
		1058	B<must not be modified or stored> by the callback. When in doubt, make a
		1059	copy.
		1060
		1061	As soon as possible after the monitoring starts, the callback will be
		1062	called with the intiial contents of the family, even if it is empty,
		1063	i.e. there will always be a timely call to the callback with the current
		1064	contents.
		1065
		1066	It is possible that the callback is called with a change event even though
		1067	the subkey is already present and the value has not changed.
		1068
		1069	The monitoring stops when the guard object is destroyed.
		1070
		1071	Example: on every change to the family "mygroup", print out all keys.
		1072
		1073	my $guard = db_mon mygroup => sub {
		1074	my ($family, $a, $c, $d) = @_;
		1075	print "mygroup members: ", (join " ", keys %$family), "\n";
		1076	};
		1077
		1078	Exmaple: wait until the family "My::Module::workers" is non-empty.
		1079
		1080	my $guard; $guard = db_mon My::Module::workers => sub {
		1081	my ($family, $a, $c, $d) = @_;
		1082	return unless %$family;
		1083	undef $guard;
		1084	print "My::Module::workers now nonempty\n";
		1085	};
		1086
		1087	Example: print all changes to the family "AnyRvent::Fantasy::Module".
		1088
		1089	my $guard = db_mon AnyRvent::Fantasy::Module => sub {
		1090	my ($family, $a, $c, $d) = @_;
		1091
		1092	print "+$_=$family->{$_}\n" for @$a;
		1093	print "*$_=$family->{$_}\n" for @$c;
		1094	print "-$_=$family->{$_}\n" for @$d;
		1095	};
		1096
		1097	=cut
		1098
		1099	=back
		1100
879	=head1 AnyEvent::MP vs. Distributed Erlang	1101	=head1 AnyEvent::MP vs. Distributed Erlang
880		1102
881	AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node	1103	AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node
882	== aemp node, Erlang process == aemp port), so many of the documents and	1104	== aemp node, Erlang process == aemp port), so many of the documents and
883	programming techniques employed by Erlang apply to AnyEvent::MP. Here is a	1105	programming techniques employed by Erlang apply to AnyEvent::MP. Here is a
…		…
1037	Keeping your messages simple, concentrating on data structures rather than	1259	Keeping your messages simple, concentrating on data structures rather than
1038	objects, will keep your messages clean, tidy and efficient.	1260	objects, will keep your messages clean, tidy and efficient.
1039		1261
1040	=back	1262	=back
1041		1263
		1264	=head1 PORTING FROM AnyEvent::MP VERSION 1.X
		1265
		1266	AEMP version 2 has a few major incompatible changes compared to version 1:
		1267
		1268	=over 4
		1269
		1270	=item AnyEvent::MP::Global no longer has group management functions.
		1271
		1272	AnyEvent::MP now comes with a distributed database that is more
		1273	powerful. Its database families map closely to port groups, but the API
		1274	has changed (the functions are also now exported by AnyEvent::MP). Here is
		1275	a rough porting guide:
		1276
		1277	grp_reg $group, $port # old
		1278	db_reg $group, $port # new
		1279
		1280	$list = grp_get $group # old
		1281	db_keys $group, sub { my $list = shift } # new
		1282
		1283	grp_mon $group, $cb->(\@ports, $add, $del) # old
		1284	db_mon $group, $cb->(\%ports, $add, $change, $del) # new
		1285
		1286	C<grp_reg> is a no-brainer (just replace by C<db_reg>), but C<grp_get> is
		1287	no longer instant, because the local node might not have a copy of the
		1288	group. You can either modify your code to allow for a callback, or use
		1289	C<db_mon> to keep an updated copy of the group:
		1290
		1291	my $local_group_copy;
		1292	db_mon $group => sub { $local_group_copy = $_[0] };
		1293
		1294	# now "keys %$local_group_copy" always returns the most up-to-date
		1295	# list of ports in the group.
		1296
		1297	C<grp_mon> can be replaced by C<db_mon> with minor changes - C<db_mon>
		1298	passes a hash as first argument, and an extra C<$chg> argument that can be
		1299	ignored:
		1300
		1301	db_mon $group => sub {
		1302	my ($ports, $add, $chg, $lde) = @_;
		1303	$ports = [keys %$ports];
		1304
		1305	# now $ports, $add and $del are the same as
		1306	# were originally passed by grp_mon.
		1307	...
		1308	};
		1309
		1310	=item Nodes not longer connect to all other nodes.
		1311
		1312	In AEMP 1.x, every node automatically loads the L<AnyEvent::MP::Global>
		1313	module, which in turn would create connections to all other nodes in the
		1314	network (helped by the seed nodes).
		1315
		1316	In version 2.x, global nodes still connect to all other global nodes, but
		1317	other nodes don't - now every node either is a global node itself, or
		1318	attaches itself to another global node.
		1319
		1320	If a node isn't a global node itself, then it attaches itself to one
		1321	of its seed nodes. If that seed node isn't a global node yet, it will
		1322	automatically be upgraded to a global node.
		1323
		1324	So in many cases, nothing needs to be changed - one just has to make sure
		1325	that all seed nodes are meshed together with the other seed nodes (as with
		1326	AEMP 1.x), and other nodes specify them as seed nodes. This is most easily
		1327	achieved by specifying the same set of seed nodes for all nodes in the
		1328	network.
		1329
		1330	Not opening a connection to every other node is usually an advantage,
		1331	except when you need the lower latency of an already established
		1332	connection. To ensure a node establishes a connection to another node,
		1333	you can monitor the node port (C<mon $node, ...>), which will attempt to
		1334	create the connection (and notify you when the connection fails).
		1335
		1336	=item Listener-less nodes (nodes without binds) are gone.
		1337
		1338	And are not coming back, at least not in their old form. If no C<binds>
		1339	are specified for a node, AnyEvent::MP assumes a default of C<:>.
		1340
		1341	There are vague plans to implement some form of routing domains, which
		1342	might or might not bring back listener-less nodes, but don't count on it.
		1343
		1344	The fact that most connections are now optional somewhat mitigates this,
		1345	as a node can be effectively unreachable from the outside without any
		1346	problems, as long as it isn't a global node and only reaches out to other
		1347	nodes (as opposed to being contacted from other nodes).
		1348
		1349	=item $AnyEvent::MP::Kernel::WARN has gone.
		1350
		1351	AnyEvent has acquired a logging framework (L<AnyEvent::Log>), and AEMP now
		1352	uses this, and so should your programs.
		1353
		1354	Every module now documents what kinds of messages it generates, with
		1355	AnyEvent::MP acting as a catch all.
		1356
		1357	On the positive side, this means that instead of setting
		1358	C<PERL_ANYEVENT_MP_WARNLEVEL>, you can get away by setting C<AE_VERBOSE> -
		1359	much less to type.
		1360
		1361	=back
		1362
		1363	=head1 LOGGING
		1364
		1365	AnyEvent::MP does not normally log anything by itself, but sinc eit is the
		1366	root of the contetx hierarchy for AnyEvent::MP modules, it will receive
		1367	all log messages by submodules.
		1368
1042	=head1 SEE ALSO	1369	=head1 SEE ALSO
1043		1370
1044	L<AnyEvent::MP::Intro> - a gentle introduction.	1371	L<AnyEvent::MP::Intro> - a gentle introduction.
1045		1372
1046	L<AnyEvent::MP::Kernel> - more, lower-level, stuff.	1373	L<AnyEvent::MP::Kernel> - more, lower-level, stuff.

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.122 by root, Wed Feb 29 18:44:59 2012 UTC vs. Revision 1.139 by root, Thu Mar 22 20:07:31 2012 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.122 by root, Wed Feb 29 18:44:59 2012 UTC vs.
Revision 1.139 by root, Thu Mar 22 20:07:31 2012 UTC