Job to keep a count of XML files

view full story

http://unix.stackexchange.com – My friend works in a IT company where he is required to keep a count of XML files inside a directory (including subdirectories). However the count using ls -LR | grep .xml or similar takes a lot of time as the count of files is in the millions. I was thinking what can be a better approach? Can some kind of background process take care of this, so that whenever there is a new file created or modification time change, it affects the counter (no. of files)? (HowTos)