It’s been pretty quiet around here recently.

Much as I wish it was because I’d been lounging on a beach somewhere, sipping cocktails and generally chilling out, it’s actually because I’ve been spending most of my time contracting on Sketch, and it hasn’t really left any space for other projects.

That’s all coming to an end in a few days, as I’ve decided that it’s time to move on.

So with a bit of luck you will see the sleeping ~giant~, erm, minnow that is Elegant Chaos slowly come back to life.

I have a large number of potential apps in mind, but at this stage I’m in no particular hurry to settle on one of them, and in fact I may take a little time out before doing anything much. I might even lounge on a beach or two, but I live in the Outer Hebrides so I will be well wrapped up if I do.

That said, if you have a project that you think I’d be interested in, don’t hesitate to get in touch.

I’ve finally got round to moving my blog Born Sleepy over to Jekyll as well.

As part of this, I’ve been rationalising which posts live where. Originally both this and Born Sleepy were part of the same site, and when they forked, I retained all the old posts in both places for the sake of any old links.

Now though I’ve decided to retrospectively tidy things up a bit. I’ll attempt to add enough redirections that old article links still work, but the indexes for both sites should now reflect just the content that is relevant for them.

As you can probably see, this site has changed!

I’ve finally migrated it away from Drupal (I was still on 6!), and it’s now a static site built with Jekyll.

I’ve probably missed a few pages along the way, so please let me know if you spot a broken link or some missing content.

Having the BBC make its Panorama program all about Apple is tabloid sensationalism, and it sends out completely the wrong message.

It’s saying to companies who attempt, in however ineffectual a way, to do the right thing: “stick your head above the parapet, and we’ll monitor you twice as hard as all of your competitors, even though they are engaged in exactly the same practices”.

The exploitation of labour in poorer countries is a massive problem, but it’s also what the current free trade, free market economies of the richer countries are largely based on.

Our cheap consumer goods don’t appear like magic from nowhere. These things only cost what they do because the people who make them were paid a pittance to work too long in dangerous conditions, and the materials they were made of were sourced in a similarly dubious way.

I’m not saying that it’s somehow easy for us as individual consumers to combat this, but it’s completely hypocritical for anyone who owns a computer, tv, mobile phone etc to single out individual companies without examining the conditions in which their own possesions were produced.

The way to solve this problem is to regulate. We need to raise the burden of proof on manufacturers and sellers that the wares they are peddling have been produced ethically and sustainably. We then need to make it illegal to import and sell things that don’t meet the standard.

That is something that can only be done by governments, and it can only be done if the political will is there to do it.

Which comes back to voters.

Which means you.

A nice quote from the developers of SQLite, who have apparently got some serious performance improvements in their latest version:

The 50% faster number above is not about better query plans. This is 50% faster at the low-level grunt work of moving bits on and off disk and search b-trees. We have achieved this by incorporating hundreds of micro-optimizations. Each micro-optimization might improve the performance by as little as 0.05%. If we get one that improves performance by 0.25%, that is considered a huge win. Each of these optimizations is unmeasurable on a real-world system (we have to use cachegrind to get repeatable run-times) but if you do enough of them, they add up.

I have from time to time been accused of being too obsessed with seemingly trivial performance issues when writing everyday code.

There is an orthodoxy based around the concept of premature optimization which seems to encourage some people to believe that performance should be wilfully ignored when writing code, and only dealt with in an isolated step, using tools like Instruments, once all the dust has settled.

Even then, there is a tendency to focus on the low hanging fruit - the top few methods that show up in a profile - and to ignore the rest, or throw up one’s hands at the prospect of improving them. Small (or not so small) overheads that show up in all the code, such as those associated with message passing, memory allocation, and that sort of thing, can easily get overlooked. Similarly, the decision to aim for a particular programming style of idiom can sometimes overlook the fact that the choices they impose have consequences, like lots of dynamic allocation, or lots of memory copying, or lots of synchronisation, or hitting memory in the wrong order and screwing the cache.

I’m not saying that the basic premise of the premature optimization argument is wrong - far from it. It does make sense not to waste massive amounts of time doing insanely complex optimizations too early, on the wrong code. It does make sense to use tools to guide you, rather than guessing. It does make sense also to write clean code that makes your intent obvious.

Most of the time in any case the biggest improvements come from picking the correct algorithms, rather than in twiddling individual lines of your code. 

What numbers like the ones quoted above show though, is that a large number of small improvements to performance can have a massive impact in aggregate. You shouldn’t obfuscate your code unnecessarily or obsessively, but if there are two ways to achieve the same aim, both of which are clean and easy to understand, and one of them is obviously more efficient in speed or space, then you’d be a fool not to choose it.

You can only make an informed decision about which implementation to choose if you have some basic awareness of performance and the implications of your choices. Aiming for a consistent style (functional, object-oriented, whatever) probably makes a lot of sense if it cleans up your code base and makes the whole thing easier to understand; but only if you acknowledge the impact is has. 

It’s not wise to just defer even thinking about all this stuff until some mythical optimization phase later. 

It definitely is wise to gain a basic understanding of how the building blocks of your language work, and roughly how the things on which you build are implemented, and to make decisions accordingly.

In case you’re wondering, the title of this post comes from the following quote by Herb Sutter:

Definition: Premature pessimization is when you write code that is slower than it needs to be, usually by asking for unnecessary extra work, when equivalently complex code would be faster and should just naturally flow out of your fingers.