I thought I’d take a stab at quick-fire journal entries.

First, we return to Helix and take a look at Kitty.

Then, a note about ClickHouse. Getting hands on with ClickHouse has helped me understand in practice what I previously only understood in theory (column-orientated datastores). In doing so, it’s expanded my horizons of what’s possible.

The beauty of the flower and its leaves in the morning light was enchanting. But what I really liked was the grain on the petals, taking down the brashness of a typical sunflower just the right number of notches.

Fifteen years ago I read a lot of what danah boyd wrote. I enjoy her research themes, and still find them important in understanding the world of teens and tech. But I lost track of her work some time ago.

So I was pleased to come across her new home, and to read Protect Elders! Ban Television!!

The piece is a piercing reminder that:

• Our evidence generally shows that social media use is, at best, correlated with — rather than the cause of — problems children might have.
• Banning kids from social media is dumb and misguided, but looks good to voters because one is Taking Action on an Issue Of The Day.

There was something reassuring about the piece, that technology isn’t destroying the young, but also not-reassuring, because the problems have deeper causes that have everything to do with the wider state of the world. I’m not sure that I agree with one of the ideas presented, that the laws are based on removing children from political discourse, but I’m also not sure that I disagree either given the state of politics in the US right now. There’s a lot in the piece to unpack, and to think about, over weeks and months.

And, everyone notices the example they are set:

When I was spending lots of time with teenagers, one of the things that they always told me was that parents were the real addicts. They couldn’t let go of their phone (or Twitter or … ). I looked around and realized how true this is. Go to a kids’ sports game or playground and you’ll see a bunch of parents staring into their devices.

Red neon signs with skulls are not typically charming. At the Brewdog bar in Edinburgh airport, however, I found this example. It is, I think, charmingly customised to its location. Further, I wouldn’t be surprised if this was the only airport bar in the world with a decent alcohol-free beer on tap.

This is something I keep trying and failing to explain, so I am writing it down to hopefully create something that makes sense. Then I can refer people to it, rather than rambling away at them for a time and leaving them slightly bewildered.

A CPU stall is created when a process uses up all of its allocated CPU, and is put to sleep by the kernel, often for 10s of milliseconds.

Sometimes this isn’t noticeable, other times it is catastrophic. It depends on how latency critical the workload is. A few 10s of milliseconds on something that takes a few minutes, like a background batch job, doesn’t matter much, but if it’s a database operation on a critical user-facing request path, perhaps it’ll be an issue. It’s one reason monitoring tail latencies is important — this kind of thing doesn’t show up in averages, only in tails.

Anyway, now we know what the problems are: what causes it? And how can we prevent it?