What attribute is responsible to keep same number of events in L3 & L4 PI servers?
By understanding L3 data is sent to L4 using PItoPI, turning off exception and compression in L4 server tags will do what you are expecting.
Tags in L3 can have (if needed) compression setting which filters and stores required data, now the tags in L4 needs no compression and exception settings to be enabled. This will ensure all the events in L3 server tags is sent to L4 server tags.
History only option needs to be disabled to get the new events from the source(L3).
It depends on the PI-to-PI configuration as well. If points are configured to be signed up for exception, you would want to use the same compression/exception settings on the target server or you will end up with more events stored on L4 than L3.
See Venaktaramesh's link below for more info.
Below KB00869 would of some help for you.
Considerations for best data match in source and target PI Servers using the PI to PI Interface
Thanks & Regards
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