Let's imagine we have one source with some logs:
80% - normal messages (all messages)
20% - specific messages (some complex regex)

Normal messages filter includes specific messages.

We need to put these messages into separate files.
Which way will give more performance?

1. 
log(source(s),filter(non-specific),destination(normal),flags(final))
log(source(s),destination(specific),flags(final))

OR

2.
log(source(s),filter(specific),destination(specific))
log(source(s),filter(normal),destination(normal),flags(final))

OR

3.
log(source(s),filter(normal),destination(normal))
log(source(s),filter(specific),destination(specific),flags(final))


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Best regards,
Koldaev Anton