Skip to main content

Riddle: When isn't free space free?

So tonight I discovered my hard drive was slowly being choked by some mysterious process writing gigs and gigs to it. So I moved 75GB of files to an external drive only to come back a few hours later and discover my free space was back down to 23 GB.

Where did 50 GB of files come from in just a few hours!?

Idea #1

Rogue process downloading large files...*cough*iTunes*cough*

I had NetUse Traffic Monitor running and it clearly showed that there was definitely not 50 GB of downloads in that time period.

Idea #2

Rogue process writing lots of log files

In my investigation of what to move to the external drive I used GrandPerspective to get a visualization and catalog of what was on my drive. Thankfully I hadn't closed that window so I could rescan and compare what had changed.  Here's the next head scratcher, it showed only a 4 GB total difference in used space between the two scans.

Idea #3

It was something on my wife's side which GrandPerspective couldn't see since it didn't have permissions to her files.

Nope, she only had 24 GB of files on her side.

Idea #4

Google for "mysterious hard drive full"

Surprisingly this got me some new ideas, like it was hidden files, or bad Time Machine backups to a non-existent external drive. Sadly they were not the problem. I even found someone with the same problem but no solution.

Idea #5

Run 'du' to show what GrandPerspective can't see

A this point I realized that GrandPerspective was reporting 104GB of "miscellaneous used space". So Googling for more info, one of the posts I stumbled on lead me to a page about Mac OSX Tiger Problems which introduced me to the BSD disk usage command 'du'. So it seemed like a lower-level command that would take some time, but would show me what GrandPerspective supposedly couldn't. Sadly it didn't and agreed with GrandPerspective that 804GB of my 931GB drive were being used while 'df -kh' agreed with the Finder that only 23GB were free. So four tools were giving me two different answers, that I had either 23GB free or 127GB free depending on which you asked.

Idea #6

Ask Google why 'du' and 'dk' can give different answers.

Sure enough, Google had an answer to why 'du' and 'dk' can differ. Turns out a process can hold onto a deleted file and the file will be unaccounted but the disk space will still be considered used. So at this point I gave in (sorry, never figured out who the offender was) and restarted my computer. Sure enough, after the Finder came back up...I had magically cleared up nearly 87 GB of hard drive space.

Moral of the story

Try restarting first, even for disk free space issues apparently. #facepalm
Labels:
Location: 19 Valley Field Rd S, Sandy Hook, CT 06482, USA

Comments

Post a Comment

Popular posts from this blog

3D Photo Viewer for Looking Glass

The Looking Glass I created my first Chrome extension, which is now live on the Chrome Web Store ! It's built for the Looking Glass , a holographic display that let's you view three-dimensional objects without glasses. I've also opened the source to the extension on GitHub. The Chrome extension allows you to view Facebook's "3D Photos", a feature they added in 2018 for displaying photos that include a depth map like those from phones with dual cameras, such as Apple's "Portrait Mode". Getting Started To use the extension, connect your Looking Glass to your computer, navigate to Facebook and open the viewer from the extension's popup menu. This will open a browser window on the Looking Glass display's screen in fullscreen mode. Opening the Viewer Once the viewer is open, the extension watches for any 3D Photo files being downloaded, so browse around Facebook looking for 3D Photos.  I recommend some of the Facebook groups de...
Post a Comment
Read more

My Journey to Fitness, a 5K, and my first Triathlon

At the finish line My name is Brian and Sunday I became a triathlete. My journey started ten months ago when I decided to get back into shape after 15 years of being obese and out-of-shape with some yo-yo dieting in the middle. What changed? I'll get to that. This weekend I competed in the first ever Rocketman Florida Triathlon which took place on the grounds of Kennedy Space Center at Cape Canaveral. In preparation I lost 50 lbs and 12 inches from my waist. But I'm getting ahead of myself. I'm a huge space buff. As a kid I wanted to become an astronaut. I went to Space Camp in Titusville when I was 10. Before that, I saw my first shuttle launch at 7 while on vacation. It was the final launch of the Challenger. I've written about that experience . I've seen three other launches since then including John Glenn's famous return to space as well as the final launch that ended the U.S. Shuttle Program. The idea of biking on the restricted grounds ...
Post a Comment
Read more

First Impressions from NoSQL Live

Today I drove up to Boston for the day to attend NoSQL Live . My experience so far within the NoSQL community has been limited to what we've built in-house at Disney and ESPN over the past decade to solve our scaling issues, more recently has been ESPN's use of Websphere eXtreme Scale , and the very latest has been my own experimentation with HBase which hasn't gotten much further than setting up a four node cluster. I've read a little about Cassandra, memcached, Tokyo Cabinet and that's about it. So before the sandman wipes away most of my first impressions of the technologies discussed today, I wanted to record my thoughts for posterity or, at the very least, tomorrow. Cassandra Cassandra seems to be the hottest NoSQL solution this month with press about both Twitter and Digg running implementations. My impression, I'm wary of "eventual consistency". I don't feel I understand the risk and ramifications well enough to design a system properly...
4 comments
Read more