Yes, the order of the FKM keys can impact the Netprobe's performance.
Keys are processed in order and therefore sorting keys in order of most likely occurrence will improve the performance of the netprobe.
As is noted in the FKM reference guide overview every time a new line is scanned by the Netprobe it will process the keys until a match is found and will then stop (See image below).
Ignore keys will be processed, followed by fail keys, and then finally warn keys. The most expensive line that can be processed by the Netprobe is one that does not match ANY key because it will be attempted against all possible keys. The sooner a match can be found the less work will have to be done by the Netprobe. Typically users add keys to the end of FKM tables when the problem is first encountered, and it is unlikely that statistical analysis of logfile keys is part of ongoing Geneos maintenance.
The following is a list that may aid in performing some basic optimizations:
There is an option called continueTriggerScan that, as the name suggests, continues through all keys until there are none left. This is a very rarely used option and has the effect of disabling ignoreKeys and impacting performance.