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Entry  12 Dec 2008, Jimmy Ngai, Info, Custom page which executes custom function 
    Reply  14 Dec 2008, Stefan Ritt, Info, Custom page which executes custom function 
    Reply  01 Jan 2009, Konstantin Olchanski, Info, Custom page which executes custom function 
       Reply  13 Jan 2009, Stefan Ritt, Info, Custom page which executes custom function 
Message ID: 552     Entry time: 13 Jan 2009     In reply to: 547
Author: Stefan Ritt 
Topic: Info 
Subject: Custom page which executes custom function 
The UDP connection you mention is only used locally for inter-process communication. When I implemented that, I 
made extensive tests and found that there is never a packet being dropped. This happens for UDP only if the packet 
goes over a physical network. Maybe this is different in modern Linux versions, so one should double check this 
again.

For remote hot-link notification, the notification is sent over the TCP link, so it should not be lost either. But 
your second point is correct. The hot-link mechanism was developed to change parameters in front-end programs for 
example. So by design it is guaranteed that if you change a value in the ODB, any client hot-linked to that will 
see the change (sooner or later). If there are many changes in short intervals (or the callback function on the 
remote client takes long time), only the last change is guaranteed to arrive. Therefore, as you correctly state, 
the hot-link mechanism is not a save replacement for the RPC layer (That's why the RPC layer is there after all).
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