Saturday, 17 March 2012

On demand - or not.

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.

Wednesday, 14 March 2012

Hold in there!

There's something frustrating me recently. I've started writing a series of blog posts about flying, but for various technical reasons I can't publish them yet and it's making me go slightly nuts. Aspiring pilots should check back later in the year, when the full force of my excitement about flying will be revealed!

I know I said when I started this blog in 2009 that I'd keep writing stuff for it, and I've been pretty lame so far, but this time it's true :)

The Long Wait

It's starting to feel like an absolute age since BA accepted me onto the Future Pilot Programme - even though it was only three months ago - and an unbelievably long time until I start in August! I figured I may as well make some notes about what's going on so far.

Visiting Hong Kong

Recently, two of mine and Emma's friends got married in Hong Kong. I had quite a good time, and I really ought to put something on this blog, so I figured I'd write a quick summary of the trip.

I've spent some time in Hong Kong before, so this time I wanted to do some things that I didn't do before. I don't want to focus on eating, drinking or shopping, because Hong Kong is good for all of those things and you can see it any guide book. If you're going to Hong Kong, read, on...