As well as enjoying flying, I work as a software developer. It's fairly interesting, so I figured I'd write up anything a bit different that I find out. It may not be new to most developers, but it is to me!
This week I discovered something interesting about the way Linux manages CPU speed. Linux is designed to take advantage of a feature of modern CPUs where they slow down if they're not being heavily used, in order to reduce power. This mechanism is known as the "ondemand governor".
In the software I write at work - which is event driven, and heavily multithreaded - it seems to be possible for us to get into a state where Linux doesn't detect that we're putting heavy load on the CPU, so it doesn't push the CPU speed back to full speed, so our application runs slowly. We're conjecturing a bit here, since there's an easy solution for us so we haven't investigated much further.
Also, I should stress that this is most likely "by design" - but it caught us out, so it could catch other people out too.