After running top, do SHIFT + m (i.e. Uppercase M).
From man top
SORTING of task window
For compatibility, this top supports most of the former top sort keys.
Since this is primarily a service to former top users, these commands do
not appear on any help screen.
command sorted-field supported
A start time (non-display) No
M %MEM Yes
N PID Yes
P %CPU Yes
T TIME+ Yes
So SHIFT + t would sort by running time.
Once you have the pid and want to investigate further, do ps -o cmd fp PID to find out what’s the corresponding command.
Ref: https://unix.stackexchange.com/questions/128953/how-to-display-top-results-sorted-by-memory-usage-in-real-time https://stackoverflow.com/questions/4802481/how-to-see-top-processes-sorted-by-actual-memory-usage https://serverfault.com/questions/479460/find-command-from-pid