Open files problem on linux

i am running in the middle of a problem rite now all of a sudden, all my applications and server was running fine and all of a sudden i see he number of open files shoot up i am checking it with this command, cat /proc/sys/fs/file-nr

when i check with this it shows "44544 0 128000" so 44544 is the number of open files.

but when i check with this command - lsof | wc -l it shows - 28384

so which one is correct? my max open files limit is 65535

ulimit -a open files (-n) 65535

i want to know the top 5 processes that is using more open files. i can get this from lsof but the count shown here is very different from the other command i mentioned above. can i get the details of the processes counted by this command "cat /proc/sys/fs/file-nr" ?

according to the below mentioned link it says we cannot, How to display open file descriptors but not using lsof command

is there a work around for me? i need to find which process started using more open files all of a sudden!