Perflib_perfdata_xxx.dat

There are several of these files in my WINNT>System32 folder. I have no control over them. Are these the famous data fiiles that have provoked so much resentment among Windows users? If not, what function do they serve? (The most recent, ..._240.DAT, appeared after I installed and then deleted Microsoft OneNote)
H.

 

Yup. Those are the files.

The %SystemRoot%\System32\Perflib_Perfdataxxx.dat files are created by the System Monitor and are useful during normal operations (usually). When you shutdown normally, the file your system monitor built most recently should be deleted..

If you have an abormal shutdown, the file can become orphaned, and after a while, quite a few may accumulate on your computer.

I have also read of these files can becoming orphaned during normal operations but no one seems real sure just why.


At any rate, very safe to delete them except the most recent version. Any older ones are worthless.