Question: Is it bad to fill up my Windows installed Drive i.e. C: ?. If yes then Why , How much space should I fill , will adding more and more files in the C drive affect my hardware performance. How much space should I leave unfilled for better performance. What could be the consequences by filling the whole drive.
Answer: Well, what instantly jumps to mind is that having a “completely full” drive may cause some of the following problems:
- May cause problems for any program that need to generate temporary files or use the disk to cache (for example installers (even to other drives), downloading, compression, etc).
- Your pagefile will be unable to expand if it ever needs to (assuming it is kept on C).
- May prevent hibernation if there is insufficent space to save RAM to disk. [Edit: as Martin points out in his answer, hibernation doesn’t need additional space when you hibernate, but instead uses up space when hibernation is first switched on.]
- Will make defragmentation very slow or impossible.
Assuming that you keep the drive defragmented, a “full” drive should perform as well as an “empty” one, so I don’t think there is much of a performance issues. [Edit2: Joel’s answer wonderfully explains how full drives have more seeking to do in spread out or full drives, which will obviously have a negative effect on performance.]
I think that 85-90% usage is the maximum recommended, but I cannot remember where I’ve got that figure from at the moment.