One does typically prefer Linux experience for a _Linux_ sys admin, but don't get me wrong that's just one of many screening question. That said, if someone doesn't have enough Linux experience to know how Linux differs from *BSD or Solaris or whatever they have time on, that seems like a valid exclusion to me. I don't tend to put any stock of claims of being able to be a quick study unless they've obviously done some interview prep on the subjects they're unfamiliar with. Best way to show you are a motivated, quick study is by being a motivated, quick study.

For context: most of my professional experience is with Linux, recreational with FreeBSD. If I'd been shown the door for failing a litmus test I'd probably be more relieved than anything. Your flippant response validates that.

When I've been on the employer side of the interview table my priorities are: does this person have a rudimentary knowledge of the required subjects and what is their problem solving process like. Basically do they know enough to handle the majority of day to day things and know where to look and who to ask when something is beyond their knowledge. Arcane trivia is of little-to-no interest to me because nobody is going to memorize every single detail. There will always be surprises. And, yes, implementation details of the load average is arcane trivia – that's precisely why this article is/was on the front page of HN.

With the scenario you've put forth it's absolutely possible to hit the ground running without having to know the gory details of how the Linux kernel calculates load average. Surely you're already monitoring I/O activity and CPU usage alongside load average. And if you're not (tsk tsk) a competent candidate would know where to look for current system information, and how to respond to the information (e.g. is this elevated load average worth being concerned about in the first place?).

> Best way to show you are a motivated, quick study is by being a motivated, quick study.

The best advice I can give is to look for successes and not failures in your candidates. Asking something tantamount to a trick question. Asking them to work through a scenario where the load average is high and the CPU utilization is low is looking for success.

> Best way to show you are a motivated, quick study is by being a motivated, quick study.

It's hard to get generalized knowledge being a quick study, it's a lot easier to get specific knowledge to work on an actual issue being a motivated, quick study. So if that's really what you're looking for, you've got to be OK with using a search engine and manual pages during the interview.