ORA-04021 Timeout when compiling package

Sometimes we face timeout error ORA-04021 when trying to compile existing package.

Following steps can help to get rid of the error.
1) Find who is accessing the object using below sql
     SELECT * FROM v$access WHERE object = 'XXRH_SUPX_ORCL_PKG';

2) Check session details using below query. SID will be from the result of above query
    SELECT * FROM V$SESSION WHERE SID IN (1040,1529,1016)

3) Kill the session which is accessing the package . Ensure that you inform osuser of these session before you kill them!
   ALTER SYSTEM KILL SESSION '1016,58335'

Go ahead with package compilation!