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Conor’s 2012 Raspberry Pi Christmas Gift Guide

Ah, memories! Wish my kiddies were old enough for one of these…

I really think this Christmas could be a lovely replay of 1982 for a lot of people, like me, who got their first home computer that year. You could have so much fun on Christmas Day messing with the RPi rather than falling asleep in front of the fire. Just don’t fight over who gets the telly when Doctor Who is on. Whilst the bare-bones nature of the Raspberry Pi is wonderful, it is unusable out of the box unless you are a house with smartphones, digital cameras and existing PCs already that you can raid for components. What you want to avoid is a repeat of me that December in 1982 with my brand-new 16K ZX Spectrum which didn’t work on our Nordmende TV until two weeks later when the RTV Rentals guy came and replaced the TV Tuner. Two weeks typing Beep 1,2 to make sure it wasn’t broken.

(tags: raspberry-pi gifts computers kids hacking education gadgets christmas)

Nintendo’s work on Miiverse Penis Drawing Detection

‘The unique feature of the Miiverse is being able to send drawings, not just text. But since the advent of the internet, there have always been those who have used it for unsavory purposes.’
‘Motoyama: we never had such a problem with our Hatena services. But, when we brought Hatena Flipnote to the West, we were caught off-guard by the amount of penises drawn by people.
Kurisu: So the team and I had to come up with a way to create a system that auto-detects those types of pictures. […]
‘Motoyama: After a week, we made very good progress on the system. Then we tested the system with Nintendo of America and told them to start drawing. It went horribly.
Kurisu: What we learned is that people enjoy drawing penises. Multiple ones. (laughs) The system was not prepared to handle that.’

(tags: nintendo image-detection ttp metrics games gaming mmo miiverse drawing)

The trench talk that is now entrenched in the English language

‘From cushy to crummy and blind spot to binge drink, a new study reveals the impact the First World War had on the English language and the words it introduced.’ Incredible comments, too…

(tags: english etymology history wwi great-war via:sinead-gleeson words language)

Special encoding of small aggregate data types in Redis

Nice performance trick in Redis on hash storage: ‘In theory in order to guarantee that we perform lookups in constant time (also known as O(1) in big O notation) there is the need to use a data structure with a constant time complexity in the average case, like an hash table. But many times hashes contain just a few fields. When hashes are small we can instead just encode them in an O(N) data structure, like a linear array with length-prefixed key value pairs. Since we do this only when N is small, the amortized time for HGET and HSET commands is still O(1): the hash will be converted into a real hash table as soon as the number of elements it contains will grow too much (you can configure the limit in redis.conf). This does not work well just from the point of view of time complexity, but also from the point of view of constant times, since a linear array of key value pairs happens to play very well with the CPU cache (it has a better cache locality than an hash table).’

(tags: memory redis performance big-o hash-tables storage coding cache arrays)

HTTP Error 403: The service you requested is restricted – Vodafone Community

Looks like Vodafone Ireland are failing to scale their censorware; clients on their network reporting “HTTP Error 403: The service you requested is restricted”. According to a third-party site, this error is produced by the censorship software they use when it’s insufficiently scaled for demand:

“When you try to use HTTP Vodafone route a request to their authentication server to see if your account is allow to connect to the site. By default they block a list of adult/premium web sites (this is service you have switched on or off with your account). The problem is at busy times this validation service is overloaded and so their systems get no response as to whether the site is allowed, so assume the site you asked for is restricted and gives the 403 error. Once this happens you seem to have to make new 3G data connection (reset the phone, move cell or let the connection time out) to get it to try again.”

(tags: scaling ireland vodafone fail censorware scalability customer-service)