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Comment ZFS (Score 2) 475

"Is there a software solution, like a file system or a file format, specifically tailored to avoid this kind of bit rot?"

Yes, ZFS is specifically tailored for this. Configure a zpool running RAID-Z2 with a hot spare or RAID-Z3. Half a dozen 6TB or 8TB disks should suffice.

Set it to auto-scrub regularly. Send logs and warnings to your email, and pay attention to them. (This is the hard part). Especially pay attention if they stop arriving. (This is even harder).

I have used Nexenta for some time, but the free product has a limit of 18TB of raw storage. If I was starting today I would use FreeNAS which has no such restriction.

The other comments about the futility of trying to do this long term are worth heeding, but that doesn't mean you shouldn't try. They key is to make this an active project rather than a passive archive, and to re-evaluate the best approach every few years.

Submission + - UK insurance company to price car insurance based on Facebook posts

johnslater writes: In a sobering development, the UK insurance company Admiral has announced a plan to assess risk based on a customer's Facebook posting habits. The Guardian reports that they 'will analyse the Facebook accounts of first-time car owners to look for personality traits that are linked to safe driving. [...] The insurer will examine posts and likes [...] looking for habits that research shows are linked to these traits. These include writing in short concrete sentences, using lists, and arranging to meet friends at a set time and place, rather than just “tonight”. In contrast, evidence that the Facebook user might be overconfident – such as the use of exclamation marks and the frequent use of “always” or “never” rather than “maybe” – will count against them.'

Comment Apple is rich enough to choose its own fate (Score 1) 251

If only Apple had the money to buy their own infrastructure...

Apple is a very rich company with $200bn+ in the bank. They got that way by taking every opportunity to grow their business. Nothing wrong with that. But sometimes that entails doing things that might not be in their best long-term interests.

Consider this: they chose to buy cloud services from other vendors because their business was growing beyond their ability to provision these services in-house. They could have chosen to do it themselves, preserving the integrity of their infrastructure, but that would run the risk of not being able to scale it out as fast as their customers demanded it, and limited their growth.

So they made the choice to outsource, maximizing their growth but taking the risks that come with that approach.

They could have taken the other path and kept their integrity. They are one of the few companies rich enough to do that. But it's not in their DNA, and their stockholders would take a dim view.

So now they have to take pictures of motherboards in the hope that they catch the bad guys doing something. Pathetic really.

Submission + - BBC optimising UHD video streaming over IP

johnslater writes: A friend at the BBC has written a short description of his project to deliver UHD video over IP networks. The application bypasses the OS network stack, and constructs network packets directly in a buffer shared with the network hardware, achieving a ten-fold throughput improvement. He writes: "Using this technique, we can send or receive uncompressed UHD 2160p50 video (more than 8 Gbps) using a single CPU core, leaving all the rest of the server's cores free for video processing." This is part of a broader BBC project to develop an end-to-end IP-based studio system.

Comment Iceland is already there (Score 1) 294

I just got back from a 6-day visit to Iceland. For the first time visiting a foreign country, I completed the trip without needing to acquire any local currency. I paid for everything using my US-based credit card using chip and signature. A couple of transactions (pay and display parking) were automated without any need for either PIN or signature.

Submission + - Radio silence at the Square Kilometer Array (

johnslater writes: The Guardian has a story on the radio silence requirements at the Square Kilometer Array in Australia. The RF requirements for the SKA are far more stringent than at the US National Radio Quiet Zone at Greenbank, to such an extent that the specialized supercomputers to control the array have specially shielded data centers, and the as-yet-unbuilt supercomputer to process the data will be located hundreds of miles away in Perth. To quote Dr John Morgan in the article: "You can guarantee that the thing that SKA will be remembered for ... is going to be the thing you have not thought of. It’s the unknown unknown."

Comment Re:Left or Right? (Score 1) 475

There's a lot of urban myth about this. In UK law the tolerance is actually 10% + 4kph, or 2.5mph, and it applies to the speedometer in the car, not to the true speed. This is merely a wiggle factor allowed for the speedometer in the car, which is allowed to read high up to the above formula, but never low.

So for a true speed of 70mph, the car's speedometer may legally display between 70 and 79.5. So it is not a excuse to speed, as the tolerance is only on the upside. A speedo that reads low is out of spec and illegal. Thus most cars have speedos that read a little high by design, in order to comply with this regulation. In my experience about 5% high is typical, so 73.5 indicated for true 70.

AFAIK any allowance by the cops over the true speed is entirely at their discretion. In theory you can still be ticketed for 71. IMHO this is a good thing, as it allows boy racers to surge along at an indicated 85, while still actually within what most cops would consider a safe envelope.

This policy is in everyone's interests:
- the car manufacturers like it because the wiggle factor means they can build the speedo to a lower, cheaper standard;
- the enthusiastic driver likes it because it gives an exaggerated impression of the car's performance (I was doing 100!^H^H^H^H90!);
- the authorities like it because it curbs excessive speed and thus enhances safety;
- we geeks tolerate it because we have our own independent measuring equipment.

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