Why is My Hard Drive Slow and Why is it so Full?

Why does my hard drive fill up so quickly?

With hundreds of gigs at one’s disposal, how do documents and pictures of a couple megs add up to fill a disk? Well, they do add up, but only to some extent. Furthermore, if you play games or store video files, you can be eating gigs at a time. Still, it seems to fill up faster than it should, and you aren’t just being a grumpy pessimist type. The glass is indeed half-empty, i.e., your drive is already half-full.

Surfing the web, downloading things, uninstalling software, and so on, leaves behind all kinds of stuff you really don’t need. It might be dangerous and full of malware or it might not, but at the very least, it is taking up space. The next article shows you a few tricks and introduces some free software you can use to get back some hard disk space.

Fine, but why is it so slow?

Well, that has to do with how your hard disk records, finds, and disposes of information. Allow an analogy involving Moose, a college athlete. Moose breezed through high school, but he plans on getting the most of his scholarship.

Moose doesn’t have a lot of the skills most students picked up long ago. He knows from observation that he has to take notes, but not how to organize them. He buys a massive, blank, notebook (paper not digital). He goes to each course’s first class and takes notes. The notes for one course begin on the first blank page after the notes for the previous course, with no pages in between. The next week he repeats the process, and so on for the term.

Obviously it is hard to keep track of everything, so he numbers his notebook pages and keeps track of where all the notes for a certain course are by writing it down in a table inside the cover of his notebook.

When Moose reads his notes, he checks his table, flips to the page for the course in question, and reads. When he gets to the end of that day’s notes, he goes back to the table, then flips to the next section and so on. Admittedly, it’s not the most efficient way to do things; but it gets the job done, and Moose survives the winter examinations.

Are you saying that is how my hard disk works?

In a word, yes – but it gets worse. Moose took some half-courses and some full courses. He doesn’t think the notes from the half-courses he finished will be useful. Worse still, his notebook is almost full.

He adds the page numbers of the notes from the half courses to his table under the heading “blank”. As far as Moose is concerned, those pages are blank, he will just erase them and write new notes on them as needed.

Now Moose goes to his first class of the next term. He dutifully checks his table, finds the first “blank” page and starts to write things down. When he runs into the next page that isn’t “blank” he goes back to the table and skips to the next available page, noting all changes in the table.

Obviously, things get worse as time goes on, and eventually Moose will spend more time flipping pages and looking at the table then he does actually reading his notes.

Your story was slower than my hard drive

True. Instead of trying to placate your anger, I will redirect it. Your Windows OS (Vista or XP) uses your hard drive just like Moose uses his notebook. This leads to data fragmentation; instead of one file being in one spot on the hard disk, it is spread all over the place. To keep track of where everything is, Windows uses a Master File Table, just like Moose did.

The good news is that Moose can copy all the notes from one class to one part of the notebook, then add the old page’s numbers to the “blank” heading in his table in order to make things faster. The better news is that there is free software that can perform the equivalent for your hard drive. This process is called defragmentation, which we cover in the final article in this series.

This post is part of the series: Reclaim Your Hard Drive’s Speed and Space

We tell you why your hard drive is slow, why it fills up so quickly, and what you can do to fix it easily and for free.
  1. Reclaiming Your Hard Drive’s Space and Speed
  2. CCleaner Will Get Oodles of Junk Off Your Hard Disk For Free
  3. Tricks to Reclaim Your Hard Disk Space
  4. Auslogic Disk Defrag: A Quick and Free Way to Speed Up Your Hard Disk