Tuesday, May 26, 2009

Mac Boot Mysteries

This is long, digressive story about diagnosing a hardware problem on a Mac; if you dislike such stories, feel free to leave now.

About a week ago, my wife Candy complains to me that her Mac won't boot up. This is my hand-me-down Mac (we have a new policy in our house: Candy gets my hand-me-down computers, and I get her hand-me-down cameras), which means that it's about 2 years old, but it has a relatively new hard drive that I installed last November. A long time ago, I had set the startup option to always run in Verbose startup mode (on demand by holding COMMAND-V upon startup, or permanent by issuing the following command:

sudo nvram boot-args="-v"

Anyway, I could see from the startup porn that she was having a kernel panic with 2 likely suspects: the fan control daemon and something about Cisco VPN. Now, Candy doesn't have a Cisco VPN, but given that this was my hand-me-down machine, that explains why some of that stuff is there. Candy hadn't installed anything in the last week or so, leading me to think that one of these two was the culprit. She had been complaining that her machine was getting slower and slower, including things like window resizing, which had me puzzled. Perhaps a dying fan was causing the processor to overheat and thus slow down?

I tried safe boot (no joy), and at this point I suspect the fan. I'm certainly not afraid to crack open a Mac (with proper respect), but replacing a fan isn't high on my list of fun things to do, so we made an appointment at the Genius bar. To Candy's credit, she had a SuperDuper! backup that was just a couple of days old, so virtually everything was safe.

We went to the genius bar where the GenX slacker (this is a compliment) booted the Mac from an external drive. I hadn't tried this (even though I have several bootable drives laying around) because I was fixated on the fan problem. After booting it up, his suspicion now lies with the VPN stuff, and I reluctantly concur (especially after he ran some fan diagnostics). Now, though, the question remains: why did this problem suddenly occur? What was his (depressing) advice to fix this problem? Reinstall Leopard and all your applications. What?!? Is this a freakin' Windows machine? I couldn't believe that was real Genius advice. I've never yet had to do a ground-up reinstall of everything, but if that's the only way...hmmmm. He was very knowledgeable, and obviously he doesn't tread in the realm of VPN stuff. He also correctly pointed out that a bad fan shouldn't cause slowness: redrawing windows is mostly handled by the GPU on the Mac. The slowness was as far as I can tell a red herring.

When I got home, the first thing I did was boot Mac OS X from an external drive and get a real SuperDuper! snapshot, getting the real current snapshot. Once I have that, I can play. Candy has already agreed to the pain and degradation of reinstalling everything, but I have to think there's a better way. Then, I had a brain storm: I took the SuperDuper! snapshot I just made and booted the machine from the external drive. Success! That suggests that some part of the internal hard drive that houses the VPN stuff has somehow gotten corrupted, but still allows it to boot using the same image from an external drive. Because I have the SuperDuper! safety net, I decided on an experiment. I reformatted the internal hard drive and ran Drive Genius on it to scan for bad sectors. Nothing of note came from that, but then I overlaid my most recent SuperDuper! snapshot back onto the internal drive.

Success! The internal drive now boots, and everything appears back to normal. I'm guessing that my bad sector theory was correct.


  • Don't reinstall everything! My record is still clean on that account: I have never had to do that on a Mac yet (and it was a once-a-year chore on Windows because of bit rot).

  • Always have good backups. This would have been a tragedy rather than a comedy if Candy hadn't been using SuperDuper!. It has yet to let me down, and it has saved my bacon on several occasions.

  • I immediately latched onto the fan because it seemed to support other observed phenomena. I should have booted it myself from an external drive and run Drive Genius, but I thought I had it figured out.

  • Stop and think. It was a good thing that we had dinner plans with a neighbor when we got back from the genius bar. It was over dinner that I had the idea of just overlaying the snapshot again. If I had started on it as soon as we got back, I would have been creating a lot of movement without a lot of forward progress. Sitting and thinking about it opened my mind to alternative options.

  • SuperDuper! rocks. I can't imagine life without it.

Monday, May 11, 2009


The economic downturn has affected conference attendance. At the conferences where I've spoken in the US, attendance seems to be down 20-30% from last year. However, it doesn't seem to have been as bad at European conferences (of course, it may just be the conferences where I'm speaking), where attendance is down only a little. It was surprising then that O'Reilly decided not to conduct RailsConf Europe this year.

However, someone has stepped in to fill the gap: RailsWayCon is happening in Berlin from May 25-27. They have gathered speakers from far and wide in what looks a rockin' good conference. If you're anywhere in the neighborhood and looking for a Ruby and Rails conference, this is the one for 2009.

Friday, May 01, 2009

Confessions of a Reformed Titilator

The Rails community has a real brouhaha on its hands, but it's a red herring that it happens to be Ruby and Rails because it's a pervasive problem in scientific and engineering fields of all kinds. It seems that a presentation at the GoGaRuCo Ruby conference (Golden Gate Ruby Conference) included a heaping pile of really racy, semi-pornographic imagery. The presenters hand-waved it away by telling the attendees that the images existed to keep everyone's interest in their presentation. And, fortunately, some people called their bluff.

Studies exist that show imagery that bores into people's basest parts (sex, violence, humor) is the easiest way to keep people interested in an otherwise boring topic. Lots of presenters use this technique to engage and keep attendees attention. I know because I've used it myself. And it's really our most slovenly kind of laziness as presenters at work. Let me explain how I've come around to this conclusion.

At RailsConf last year, Joel Spolsky did one of the morning keynotes. As his first slide, he showed a glamor shot of Angelina Jolie and said (I'm paraphrasing) "I always show this as my first slide because I always get better evaluation scores on my keynotes when I do." His next slide showed Brad Pitt, with his shirt open, and Joel added "And, just to be demographically fair, I show this one next." Joel was plugging into 2 techniques for capturing attention: sex and humor. And it works on some level. The crowd (mostly) loved it. In his keynote, it was basically gratuitous: he never used it for anything other than pure pandering. But I'm always on the prowl for effective presentation tricks, so I borrowed Joel's trick, but with a twist.

In my Ceremony & Essence keynote, which I gave at a hand-full of Ruby events last year, I had a similar picture of Angelina and Brad at the start, using it to get a laugh right out of the gate. In a keynote, if you can get people laughing early, they loosen up more and are more likely to laugh more and emote more back to the presenter. However, my use wasn't merely gratuitous. I used other images of Angelina (and Brad) throughout the talk as an anchor point, serving two purposes. First, because everyone laughs up front, seeing a similar image reminds them of that, making it more likely they'll laugh again. The other purpose was to pull the narrative along. Bringing up a topic early in a presentation, then allowing people to forget it, then bringing it back at an unexpected time is one of my favorite techniques in presentations. It allows attendees to make connections between disparate things that have more impact when you "force" them to make the connection themselves, rather than beating them over the head with it. For example, I brought Angelina up again when talking about demand for developers outstripping the supply, showing a publicity photo of her in the movie Hackers. This is a not so subtle anchor point that hopefully makes people realize that one of the reasons that the developer demand outstrips supply is the paucity of female developers, which hopefully makes people ponder that a bit. I use Angelina (and, to a lesser extent, Brad) throughout the talk as those kind of anchor points. Now, realize, these images are in no way pornographic. They are just publicity photos of famous actors. However, I was sensitive to the fact that some women might find this unsettling, so I made a deal with myself: if anyone every complains about those images, I'll remove them (and restructure the talk) with no questions asked.

That happened earlier this year. One attendee at a keynote wrote me a very nice note afterwards telling me that she wasn't comfortable with the imagery of Angelina in the talk (and that the presence of Brad didn't help). That was my cue to stop using that imagery and find other anchor points to make my points. Her email made me realize the pervasiveness and toxicity of this kind of imagery, and that, while convenient, it was ultimately just laziness on my part. Why do you think that so much entertainment falls back on sex and violence to keep people interested in otherwise pretty dull drivel? Watching a show like The West Wing), which doesn't traffic in that kind of stuff, shows that quality writing doesn't have to fall back on gratuitously titillating material. Ultimately, using sexually provocative material in a technical presentation is just lazy -- when we do it we're not spending the time to come up with really compelling metaphors to represent something, relying instead on the basest of currency. Presenters, myself included, need to do better.

Lots of people who aren't affected by this will say that this is a tempest in teapot, and that the offended parties are over reacting. Insidious misogyny is like lazy racism: people who engage in it hide behind a casual facade of "Oh, really, that was offensive"? Yes, by the way, it was.

Let me re-iterate a point: this isn't about Rails or the Rails Community (I still haven't gotten my official code ring and Certificate of Membership for this "community", by the way). On average, presenters at Ruby and Rails conferences put a lot of effort into creating compelling presentations, paying attention to metaphor, presentation style, compelling imagery, etc. The conferences where I attend the most talks are Ruby/Rails and the Tri-Fork conferences (JAOO and QCon. Kudos to presenters that care about creating compelling presentations. Only sometimes pushing the envelope on what's edgy entertainment crosses a line, which is what happened in this case. It could happen at any technical conference where the presenters are pushing hard on the creative aspect of technical presentations.

I strive not to be lazy when I put together presentations, to find compelling metaphors that don't inadvertently offend entire groups of people. I think it is an important maturity step for engineering and software communities to vote with their feet: outrage only goes so far, but notifying those who lazily offend effectively sends the message that it's not OK.