System restore eating up hard drive space?

Question

I had maximum allotted system restore space for a drive set to about 4 GB But how could I gained 25 GB of free space on that same drive on turning system restore off ?

Edit:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SystemRestore

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SystemRestore\Cfg

Answer 1

Windows does not always automatically delete everything in the restore directory other than the 4 GB you set it to. You also could have had some malware in the restore directory. Windows will delete most stuff from the restore directory when you turn it off, so it can delete some malware files (but not always).

Answer 2

The problem is that on XP, it looks like Microsoft simply ignores your setting.

From The Registry Keys and Values for the System Restore Utility for XP :

DiskPercent

This value relates to the percentage of disk space that System Restore uses for its data store. The default value is 12 percent. The data store size is always calculated as "max(12 percent, DSMax)," regardless of the size of the hard disk.

DSMax

This value specifies the maximum size for the System Restore data store. The default size of the data store is 400 MB. The data store size is always calculated as "max(12 percent, DSMax)," regardless of the size of the hard disk.

However, the 25 GB you freed on a 40 GB disk is 62,5% rather than 12%. This means that the whole algorithm is non-functional, so there are actually no real limits. One hopes that this was corrected in later versions of Windows. However, such a malfunction can easily pass unnoticed, since Windows is supposed to automatically liberate this space if required.