XP: Master File Table (MFT)

If you are using NTFS, by default NTFS would reserve 12.5% of your free diskspace for MFT.
You can increase this percentage in HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem.
Add a key by the name “NtfsMftZoneReservation”
with the REG_DWORD value of 2. DWORD value of 1 is interpreted as 12.5% ,2 as 25% and so on.
This trick is benefit if you installed many program, because MFT utilization is going to be high.