If you’ve been using computers for long enough, you’ve probably faced unreadable file formats or changes in distribution media: How do I open this old WordPerfect document? How am I going to read those files stored on a ZIP disk? Photographic prints and print editions of books have much less demanding requirements for seeing their contents. You found a box of slides from the 1960s? No problem; just hold them up to a light. In fact, if you have a good slide scanner or projector, despite their age, the pictures might still be of higher quality than images produced by your compact digital camera! The problems of unreadable file formats and changes in physical media are unique to the digital age. Or so some might have you believe (especially those pushing cloud services).
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Recovering from hard drive woes — Part III
I woke my computer up from sleep and tried to run ssh. Surprise alligators! I encountered the odd error message “You don’t exist! go away!” It turns out that my dying hard drive had trashed some very important system files containing my computer login and password information. Trying to start up Terminal, I got the error “The administrator has set your shell to an illegal value”. I couldn’t access a large chunk of my files (due to lack of permissions) and my Dock was totally trashed. Solution? Start X11 from your utilities folder.
Cache-as-cache-can
Thailand was tragically flooded last year. The number of surprise alligators in the region also likely increased. As home to much of the world’s production capacity for hard drives, the shutdown of facilities caused the cost per gigabyte stored on magnetic hard drives to balloon to prices not seen since the middle of the last decade. Demand dropped for hard drives. Value-driven consumers may have opted for alternatives such as more expensive solid state drives (SSDs) or removable media like DVDs. Other purchases may have been deferred, playing catch-as-catch-can with hard drives already owned until prices begin to have some semblance of normalcy. The obvious. But none of this would have merited such a… cache-y blog post title.
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Recovering from more hard drive woes
Yes, I’m still using the same nonereliable hard drive that resulted in frequent beach balling. On Sunday, it had some more surprise alligators in store for me and decided to render my hard drive unbootable by corrupting the file system journal used to recover from sudden crashes/loss of power. My first instinct was to run the Disk Utility repair feature on the drive, but this was a no-go because, firstly, I was using Filevault 2, Apple’s full-disk encryption software.
When life is a beach ball
Do you have a Mac that beach balls (colourful pinwheels that produce colourful language) for 30-60 seconds at a time when you’re not running a computationally intensive task? Your hard drive could be dying. I hope you’re backing up. But I’m not writing this blog post to convince you that backing up your data regularly is a good idea (but it is, though). Instead, I’m going to show you how to see if that is indeed what is causing the beach balling and, if so, how to keep on tempting fate by keeping your failing hard drive chugging along while reducing your unwanted trips to the beach ((Is it any wonder why computer scientists tend to be so pasty?))
Nonereliable
If your pocket calculator made a mistake every ten operations, would you still use it? Or if the brakes of your wheeled-vehicle of choice only worked 99.9% of the time, would you keep using it? Or what if one in every thirty flushes resulted in your toilette backing up and surprise alligators streaming out? After I lost all the data on my phone, save the Chuck Norris-like audio files, I started thinking about what technology I’ve abandoned because it was so unreliable that it was more trouble than it was worth, or “nonereliable” ((Yes, this entire blog post exists just so that I can make this word a “thing”)). More generally, I began to wonder what makes things or people so unreliable that we’re better off without them. So, in the blog post, I’m just thinking aloud, considering a few examples of things I consider to be unreliable and trying to determine some factors that influence whether I continue to rely on them.
I am Customer. Hear me ring!
Prologue
A fair numbers of people are under the impression I don’t own a cellular phone. I do. ((I’ve had one for a decade, now. I’m just very bad at answering calls and haven’t figured out this “voicemail” business, so I usually don’t give out my number.)) In fact, as of September, I’ve been the unhappy owner of an Android phone that’s more “special” phone than smartphone. The reasons for my discontent, as I’ve alluded to in a past blog post, lie in both hardware and software. Two weeks ago, I noticed that a minor software update was available for my phone (version 2.1 to a more recent version 2.1) and I thought that it might at least help reduce the number of random crashes/reboots I was experiencing. I expected to be no worse off, in any case. Instead, this software update managed to sour my opinion of both WIND Mobile and Android.
Debeakered: One year and 49 posts later
It’s been a year since Jorge managed to convince me to start blogging. Things have mostly been downhill since the 15K+ views for my iPad environmental impact analysis, but that was mostly to be expected, given the media coverage around iPad at the time. Besides, many of the views are just from spammers. However, truth be told, most of my personal favourite posts such as the Tragedy of the Commons 4-part series and Peddling an idea were written when I used to spend more time thinking about and writing posts.
Thoughts on programming for all: Part IIb — Downsides
Last week, I discussed one of the downsides of students being taught to think algorithmically, even if they absorb it all. Unfortunately, just because students can pass an introduction to programming course doesn’t mean they have any understanding of code that they or anyone else has written. Whenever I teach a course, I make a point to mention cargo cult programming and warn students not to fall into that trap.
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