Definition

Common properties available in via in all JGroups protocols, via inheritance from the org.jgroups.stack.Protocol class.

Configuration Parameters

down_thread

Whether the protocol should create an internal queue and a queue processing thread (aka the down_thread

) for messages passed down from higher layers.  The higher layer could be another protocol higher in the stack, or the application itself, if the protocol is the top one on the stack. If true (the default), when a message is passed down from a higher layer, the calling thread places the message in the protocol's queue, and then returns immediately.  The protocol's down_thread is responsible for reading messages off the queue, doing whatever protocol-specific processing is required, and passing the message on to the next protocol in the stack. Beginning in JGroups 2.5 this queue/thread mechanism has been removed and this setting will be ignored if set.  See also JGroupsProtocol.

up_thread

Conceptually similar to down_thread, but here the queue and thread are for messages received from lower layers in the protocol stack.  The default value for up_thread is true. Beginning in JGroups 2.5 this queue/thread mechanism has been removed and this setting will be ignored if set. See also JGroupsProtocol.

down_thread_prio

Thread priority that should be given to the down_thread, if it is used.  See the java.lang.Thread javadocs for the meaning of thread priority. Default is 1.

up_thread_prio

Thread priority that should be given to the up_thread, if it is used.  See the java.lang.Thread javadocs for the meaning of thread priority. Default is 1.

stats

(Since JGroups 2.3) Whether the protocol should collect protocol-specific runtime statistics. What those statistics are (or whether they even exist) depends on the particular protocol.  See the org.jgroups.stack.Protocol javadoc for the available API related to statistics. Default is true.