Does switching from exactly once to at least once semantics have a peformance impact in PI

[angeloruggiero]

Hello,

I am trying to improve the performance in terms of messages processed a secound in PI by scaling up.

i.e increase the number of nodes, threads, parallism of the REST and Kafka adapter involved.

I was wondering if the Exactly Once Semantics in PI generates more load compared to At Least Once Semantics.

Does anyone have any view/experience on performance and use of system resources of these PI Semantics.

regards

Angelo

[anupam_ghosh2]

Hi Angelo,

                 In exactly once mode of delivery, PI has to guarantee that there will be no duplication of message same flow. This needs a high level of monitoring   and checking content of the message every time it is delivered to the target system. Therefore Exactly once mode of service increases operational complexity  and hampers system performance.

On the other hand, at least once mode of delivery can deliver a message more than once, but no message should be lost. As Data duplication is not an issue therefore atleast once mode of delivery takes less system resource and reduces complexity.   

Thus at least once mode of delivery is preferable over exactly once mode if system performance is the criteria to decide. 

Regards

Anupam