system ASP increased from 50% to 70% in 1 day

We have two V4R5 and were  normal IPLed  about a  week back.
The system ASP of both  machines howers around 50% usually.
 It was okay till two days back. But yesterday, one of the m/c showed an
ASP of 70%.

We collected disk info and printed for both machines.
The m/c whose ASP was still 50% has temporary space used as 1.6% while the
m/c whose ASP was 70% has temporary space as 20%. The user libraries have
about the same amount  of data as for the last 1 month.

I have a good hunch that "temporary space" will be free once system is
IPLed.
I want to know how this "temporary space" gets filled and whether I can see
it .
Can I get this space back without IPL or taking the system to restricted
state ?

Thanks
Santosh.
e- mail at :  santoshp@xxxxxxxxxxxxxxxxx
FPC-IS, ITS, Tata Steel.
Jamshedpur, India.
Tel : 2147095 (O) .