HA JMS persistence logic for JBossMQ

[malmit]

Just curious is anyone knows the persistence logic behind HA JMS. Does JBoss:
a. upon receiving a persistent message always insert the message into the database
b. keep a certain number of messages in memory until a threshold is reached

My best guess is that it would be doing option a because it is the most reliable but if it is using option a then a serious overhead is introduced each time a message is sent. Does anyone know what is happening behind the scenes in JBoss?

[genman]

It's always storing them. This is preferable to potentially losing messages.