Dear Seniors
Yesterday I found the following file

-rw-rw---- 1 oracle oinstall 4079144602 Aug 15 18:13 nmh1_diag_9335.trc

has all of a suddern reached upto 4 Gb and It is occupying more space and I would like to remove this file.
Befeore removing please Help me know what is this file talking about ?when I gone through it I found some informations that I cant understand,

How can I delete this file as this is online file and cant be removed.
is there way to remove without rebouncing the DB?

PLease help me out of this problem

With Kind Regards
Kamal