Here is some general logging info you can enable in your notes.ini. The first entry will log the start of each view rebuild by the updall task so you can calculate the time it took a view by comparing two messages:
; Show some log entries when the updall/update runs
; show the number of transactions
; Show logfile entries when semaphore waits time out
; Show the thread ids
; And show a semaphore wait log entry after ten seconds waiting.