Sun Java System Message Queue 3 2005Q4 Administration Guide |
Chapter 15
Physical Destination Property ReferenceThis chapter provides reference information about configuration properties for physical destinations. These properties can be set when creating or updating a physical destination. For auto-created destinations, you set default values in the broker’s instance configuration file (see Table 14-3).
Table 15-1 Physical Destination Properties
Property
Type
Default
Description
maxNumMsgs1
Integer
-1
Maximum number of unconsumed messages
A value of -1 denotes an unliimited number of messages.
For the dead message queue, the default value is 1000.
maxBytesPerMsg
String
-1
Maximum size, in bytes, of any single message
Rejection of a persistent message is reported to the producing client with an exception; no notification is sent for nonpersistent messages.
The value may be expressed in bytes, kilobytes, or megabytes, using the following suffixes:
b Bytes
k Killobytes (1024 bytes)
m Megabytes (1024 x 1024 = 1,048,576 bytes)An unsuffixed value is expressed in bytes; a value of -1 denotes an unlimited message size.
Examples:
1600 1600 bytes
1600b 1600 bytes
16k 16 kilobytes (= 16,384 bytes)
16m 16 megabytes (= 16,777,216 bytes)
-1 No limitmaxTotalMsgBytes1
String
-1
Maximum total memory, in bytes, for unconsumed messages
The syntax is the same as for maxBytesPerMsg (see above).
For the dead message queue, the default value is 10m.
limitBehavior
String
REJECT_NEWEST
Broker behavior when memory-limit threshold reached:
FLOW_CONTROL Slow down producers
REMOVE_OLDEST Throw out oldest messages
REMOVE_LOW_PRIORITY Throw out lowest-priority
messages according to age;
no notification to producing
clientREJECT_NEWEST Reject newest messages;
notify producing client with an
exception only if message is
persistentIf the value is REMOVE_OLDEST or REMOVE_LOW_PRIORITY and the useDMQ property is true, excess messages are moved to the dead message queue. For the dead message queue itself, the default limit behavior is REMOVE_OLDEST and cannot be set to FLOW_CONTROL.
maxNumProducers2
Integer
-1
Maximum number of message producers for destination
When this limit is reached, no new producers can be created. A value of -1 denotes an unliimited number of producers.
maxNumActiveConsumers3
Integer
1
Maximum number of active message consumers in load-balanced delivery from queue destination
A value of -1 denotes an unliimited number of consumers. In Sun Java System Message Queue Platform Edition, the value is limited to 2.
maxNumBackupConsumers3
Integer
0
Maximum number of backup message consumers in load-balanced delivery from queue destination
A value of -1 denotes an unliimited number of consumers. In Sun Java System Message Queue Platform Edition, the value is limited to 1.
consumerFlowLimit
Integer
1000
Maximum number of messages delivered to consumer in a single batch
In load-balanced queue delivery, this is the initial number of queued messages routed to active consumers before load balancing begins. A destination consumer can override this limit by specifying a lower value on a connection.
A value of -1 denotes an unliimited number of consumers.
isLocalOnly2
Boolean
false
Local delivery only?
This property applies only to destinations in broker clusters, and cannot be changed once the destination has been created. If true, the destination is not replicated on other brokers and is limited to delivering messages only to local consumers (those connected to the broker on which the destination is created).
Boolean
false
Local delivery preferred?
This property applies only to load-balanced queue delivery in broker clusters. If true, messages will be delivered to remote consumers only if there are no consumers on the local broker; the destination must not be restricted to local-only delivery (isLocalOnly must be false).
useDMQ2
Boolean
true
Send dead messages to dead message queue?
If false, dead messages will simply be discarded.
1 In a cluster environment, applies to each individual instance of a destination rather than collectively to all instances in the cluster
2Does not apply to dead message queue
3Queue destinations only