| Item |
Section |
Comment |
Response |
| joefialli-1 |
4.1.1 |
Not really a comment, just additional info on GMSAdapter.registerMessageListener. Just wanted to add that there is only one handler per component name. Subsequent message listeners added for same componentname, replace the previous one. Only last handler is used. There is nothing in details that states that this would be called more than once. I just wanted to provide this feedback so the implementer is aware of this. Other GMS notifications allow multiple handlers, just not message and failure recovery handlers. |
Response from functional spec/one pager author |
| joefialli-2 |
4.1.1 |
Additional info again, noticed that the sendMessage is sent during transaction commit. Just want to emphasize that gms message delivery is not part of XA transaction |
|
| joefialli-3 |
4.1.1 |
the registered message listener should be a fairly quick operation. otherwise, it will tie up thread resources looking to process the next incoming gms message. Beware of any synchronization or locks within message handler since there are potentially multiple instance of the message handler running at once. |
|
| joefialli-4 |
4.1.1 |
gms messaging is asynchronous between instances, there is no guarantee of message delivery ordering with asynchronous message handling. |
|
| joefialli-5 |
4.1.1 |
if message frequency is quite high and size of individual messages are small, performance may benefit from batching muliple calls. HA does batching of its replicated sessions for performance reasons. So one gms messages contains a number of replicated session data (sent every so many milliseconds. If messaging frequency is not high, then batching is not necessary. Regrettfully, gms does not provide this batching itself. |
|
| joefialli-6 |
4.1.1 |
informational comment. new for GlassFish 3.2, there will be a mechanism so administrator can enable SSL for gms tcp transport. Without this configuration, this data will be sent in clear over network. See GMS-1.0.03 in GF 3.2 GMS Requirements . GF-14664 |
