OraGlance

OraGlance is a lightweight oracle performance monitor tool , developed by parnassusdata.com . It will only focus on most important metric .

you can easily run it without any prerequisite. It will ask for few permission:

grant select on gv_$active_session_history to $USER_NAME;
grant select on gv_$SQL to $USER_NAME;
grant select on gv_$SQL_MONITOR to $USER_NAME;
grant select on gv_$SQLSTATS to $USER_NAME;
grant select on v_$database to $USER_NAME;
grant select on gv_$instance to $USER_NAME;
grant select on gv_$statname to $USER_NAME;
grant select on gv_$sysstat to $USER_NAME;
grant select on gv_$osstat to $USER_NAME;
grant select on gv_$dlm_misc to $USER_NAME;
grant create session to $USER_NAME;

OraGlance is free software , use it as you like.