Regular behaviour, I note, beginning to rile in performance - it points to a bore (8,3)
I believe the answer is:
drilling rig
'it points to a bore' is the definition.
The definition suggests a singular noun which matches the answer.
'regular behaviour i note beginning to rile in performance' is the wordplay.
'regular behaviour i' becomes 'drilling' (I can't justify this - if you can you should believe this answer much more).
'note' becomes 'g' (musical note).
'beginning to' says to take the initial letters.
'performance' is an anagram indicator.
The first letters of 'rile in' is 'ri'.
'g'+'ri'='gri'
'gri' with letters rearranged gives 'rig'.
'drilling'+'rig'='DRILLING RIG'
Can you help me to learn more?
(Other definitions for drilling rig that I've seen before include "Oil platform" , "Oil well structure" , "making an impression in Brent?" , "Parade-ground uniform" .)