When I run the query below to find out for what file/tablespace the buffer busy waits is occurring for,

select
d.tablespace_name,
sum(x.count) total_waits,
sum(x.time) time_waited
from
sys.x_$kcbfwait x,
sys.dba_data_files d
where
x.inst_id = userenv('Instance') and
x.count > 0 and
d.file_id = x.indx + 1
group by
d.tablespace_name
order by 3 desc
--
SYSTEM 52964 219146
RBS 2644 1346
DATA 14 18
INDEXES 1 0


I see that the system tablespace has the highest waits, what does this mean, I thought buffer busy waits occur on waits for blocks/freelists for inserts??

Thanx in advance.