* Posts by Ogi

153 posts • joined 13 Nov 2009

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Bank in the UK? Plans afoot to make YOU liable for bank fraud

Ogi

That "Verified by Visa" crap is the only reason I use a credit card ( Credit cards don't prompt the verified by visa window when online shopping). Really VbV the most useless thing I have ever seen, and works so rarely that it can make a 2 minute online shop last 30+ minutes.

Quite frankly, things are going in such a bad direction with banking, that I have switched to cash only. Apart from the credit card for online purchases, everything else is cash. No need for a card reader, a PIN, some sort of fancy in-phone-contactless-app crap or other tracking system wrapped in a security nightmare that I will be liable for. When I want to buy something I just put down the cash, with no faf.

I also rediscovered the joy of actually going into my branch and dealing with my account with a human being. Usually I can get problems fixed quickly, and my complaints have to be dealt there and then by the manager rather than a ticket logged somewhere in Bangalore after waiting 30+ minutes on the phone. Of course, because everyone does online banking now, the branch is usually really empty as well.

Although I concede that not everyone has a local branch nearby, I would imagine most do. Bank branches are pretty common, along with a pub and post office, even in small towns.

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Daft draft anti-car-hack law could put innocent drivers away for life

Ogi

Re: Bah

I foresee a thriving future industry of ripping out all the stock electrics/computers in a car, and replacing them with open source alternatives that give full control over the car back to the owners, as it should be.

Which of course, is why they are trying to make such modifications illegal.

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Dutch students serve up world's first 'drone café'

Ogi

Re: Rule 34

Well... not a fleshlight, but for the lonely woman (or man, if that is your particular bent):

https://www.youtube.com/watch?v=pZCVG7zUaRA (NSFW, depending on how puritan your workplace is)

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Why we should learn to stop worrying and love legacy – Fujitsu's UK head

Ogi

Or the 2000's, with i-this, i-that, i-everything. Although that has somewhat spilled into the 2010's.

No idea if there is a designated letter for the 2010's though...

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London to Dover 'smart' road could help make driverless cars mainstream – expert

Ogi

Re: computer aided burglary.

To be honest, I think that died out when car radios became really quite cheap. For £30 you can buy a brand new mp3/bluetooth/dab/latest_flashy_thing online, which works just fine in your car, and comes with a guarantee. Why would I risk buying something with scratches and wires sticking out, from a dodgy guy down the pub? Even for £10 it really isn't worth it. Not to mention the age old story of the thief then taking note of your car, finding out where you live, and nicking the radio all over again to resell.

Then there was the whole "Radio PIN" thing, and detachable covers, which made it harder to resell. Even if you knew a bent reprogrammer, and after paying them to work their magic you would find you might end up with a fiver profit.

Along the same lines, car alarm systems got better and better, so it rarely was worth the risk just for the radio. If you have to disable the entire alarm system just to get at the car radio, you might as well take the whole car at that point.

And yes, those custom in car entertainment systems are harder to get out of the car, but go on ebay and you will still find a raft of them. Turns out some of them are quite expensive even second hand.

I do think though, that there has been a reduction in car thefts. From what I can see, criminals target bikes round my area far more. Which makes sense, bikes are easier to nick, easier to keep hidden, easier to break for parts in your living room, and some loons will actually spend £2-4000 on a bike, meaning a decent profit for not much effort. Had a neighbour complain that it would cost her £100 for a new bike wheel, because someone nicked hers (she locked the frame and rear wheel only). Never knew that bike wheels have become so expensive.

Every morning in the early hours, outside my building, you can hear saws and hammers as the local youths try to break the bike locks in the bike parking area, yet nobody touches cars any more. Probably because there are very few chop shops around nowadays, and not everyone has the space to break a stolen car for parts without anyone noticing.

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Labour: We want the Snoopers' Charter because of Snowden

Ogi

Re: You can see what they're aiming at

@Tomato42

Indeed, or even Turkey, which has gone all in into authoritarianism, shutting down all media ( and arresting journalists) that are not pro-government. Not a peep from anyone in Europe, in fact Turkey just got 6 billion EUR and a fast-track membership offer.

Interestingly, the justification there is that by being against the current government's policies, they are "supporting terrorism". Funny considering two of those arrested were done so because they exposed Turkey's support for ISIS. So its all a matter of definitions really.

Food for thought, what with all the "anti-terror" laws on the books nowadays, at some point having a non-govt approved opinion may well qualify for application of said laws, especially when the government gets to decide what is terrorism. It happened in Turkey, could it happen here?

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Fail0verflow GitHubs PS4 Linux loader

Ogi

Re: I just... why?

Opera was the only one on the N900 that I found fast and usable, so set it as my default. Not sure if it supports HTML5 (my n900 has ceased turning on unfortunately :( ) but all sites I visited worked well and looked good up until 2015.

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Ogi

Re: I just... why?

> Frankly, if you penguins are wanting to do something unusual, write a proper replacement browser for my N900 and its aging MicroB. Now THAT would be useful!

Just to ask, what is wrong with Firefox or Opera on the N900? Sure out of date by modern phone browsers, but far better than microB. It is even the pre-webkit Opera, which I think was one the best out there.

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Microsoft has made SQL Server for Linux. Repeat, Microsoft has made SQL Server 2016 for Linux

Ogi

Hmm... perhaps we need to do some more testing/research?

Worst case scenario... its raining roast bacon pieces!

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Ogi

Re: Imagine my joy

Aaah "Vigor", back when "obligatory xkcd" was "obligatory userfriendly strip":

http://ars.userfriendly.org/cartoons/?id=20000108

One of the first online comics I found, and got me hooked on the medium. Still one of my all time fave comics, and now I feel old, lol.

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Flash is too fat. A glut of supply means growth is slower and slower

Ogi

Re: Flash is the future - in a way

Yeah,

I switched to SSD for my root/boot drive on all my machines. 64GB is enough on my laptop, and the desktop has 32GB SSD, 500GB Disk, and mounts storage from my file server (which is a BSD box, running ZFS with 2x128GB SSD read/write cache and 8 disks for long term storage).

I last benchmarked the file server at 700MB/s, which is much faster than I can really push it (gigabit ethernet). Having a hybrid disk/SSD setup is the way forward I think. I don't notice the slow speed of the disks because I hardly ever read/write more than 128GB at once. As such my working set sits in the SSD caches, and get dumped to the drives over time. Essentially like a tiered storage solution.

The laptop and desktop boot so fast, and are so responsive now, that the SSD was a better investment than a new computer.

The only reason I don't put a disk it on the laptop as well is because of space/power constraints, although in theory I can replace the DVD drive bay with a second disk bay, and put in some spinning rust there.

I looked into replacing the 8 disks in the FS with SSDs and getting rid of the two cache SSD's, but 1TB SSDs are still waay too expensive for a SOHO environment (unless you really need the raw performance). I suspect that by the time 1TB SSDs come to the price of a 1TB hdd, we will probably have 14TB disk drives, and a hybrid system can give you decent performance with better storage.

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Intel shows budget Android phone powering big-screen Linux

Ogi

" Reason one is that only the technically proficient will want to use something like that. The market would possibly sustain one or two models at best but not enough to satisfy the corporate greed involved. " ---

Indeed, parent basically described the old n900, which was a Linux PC with a phone slaved to it. I loved mine, lots of nerds loved theirs (so much they tried to resurrect it with the neo900), but the wider world went "meh", until Apple came along with the iPhone.

What we want, is not what the public wants. The n900 didn't even manage to sustain one model in the market, let alone more. And that was back in 2009, when the competition wasn't as fierce as now, and the "app market" was still not totally captive by Apple/Google.

Maybe with persistence, marketing and refinement it could have been number 3 in the mobile OS options list, but Nokia couldn't financially sustain it, and after Elop got a hold of Nokia, a Linux based phone had no chance of surviving.

Now, I think the best we can hope for is some sort of hybrid like this. Still not sure of the security implications. There are so many apps on my phone, and I don't trust any of them not to be buggy or malicious, that I refrain from logging into sensitive places.

I have actually taken to carrying a second phone, running Cyanogenmod without any apps just for SSH and other sensitive stuff.

At this point I have been pondering starting an OSS project to take AOSP, or Cyanogen mod, and rip out all the stuff down to the bare essentials to run the phone and wifi, then build a GNU Linux distro on top of it. No Apps, no Android compatibility, but as close to a Linux OS as you can get, something akin to my old N900, or if I can't get the phone bits to work, my old N810.

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Eurovision Song Contest uncorks 1975 vote shocker: No 'Nul point'!

Ogi

" inexplicably - the EBU said "Nope."

Replace "inexplicably" with "didn't offer enough cash to the right people. I don't think it is a geographical constraint on who can join Eurovision, just depends on whether enough palms are greased, and whether the expense is worth it for the country that wants to partake.

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Dialog box shut: Now Microchip is set to gobble up Atmel

Ogi

Re: Missing the point of Arduinos

The irony is, when I first tried to get into microcontroller development, I got an Atmel starter kit (late 90's I think it was), with the "Keil" software, which was windows only.

Having got the starter kit, I found there to be virtually no support in the open source world for development and programming of Atmel uC's. All the hobby electronics people were using PIC uC's, and the open source assemblers/simulators were all for the PIC uC's.

So after lots of frustration, I gave up, stuck the atmel in the attic, and bought a Maplin PIC starter kit, which I then started using. The OSS software was clunky, and didn't support most PIC's (the "SDCC" software still only really supports PIC16 last I checked) but it worked, and allowed me to write C for the uC on my Linux workstation.

Fast forward a couple of years, and a lot more investment in PIC based hardware, and just when I got comfy with PICs, and Atmel "Arduino" is now the best dev environment for Linux development of uC's, and have spawned a lot of OSS tools for development. Conversly the PIC OSS scene has stagnated somewhat.

So now have been asking myself, whether to move across to Atmel again, as there is a lot more vibrancy and progress in Atmel OSS. Although who knows what will happen, now that Microchip are buying Atmel. Maybe both families will get some love?

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Was Android moving to OpenJDK really a Google gift to devs?

Ogi

Re: From a developer perspective

Maybe they could have done as Nokia did with the n900, and let the developer use any language they wanted?

the N900 had bindings/libraries for perl/java/python/ruby/C/C++ and possibly others, all the apps looked the same UI wise, and acted the same, just written in whichever language the developer felt was most suitable.

You could even compile standard Linux software without modification on it. Sure it didn't follow the look and feel of proper apps, but the fact you could do it all and have something usable on the phone was impressive to me.

(Used to write apps for the N900/Maemo, never went into Android app dev due to being forced to use one language, and one I was not particularly keen on. Also I felt Android to be a generational leap backward in mobile OSes)

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Launch embiggens Galileo satnav fleet

Ogi

Re: The US military has announced that if ...

Yes, Russia provided tax breaks to devices that supported their own technology (logic being, that any loss from tax revenue is offset by increased licensing revenue of the technology, plus its widespread adoption).

A lot of the location chip designers added it, because having two networks decreases the time to get a fix. I am sure when the EU and Chinese networks become functional, they will add those as well (although ideally you want an odd number, so you can quorum, in case one superpower decides to turn off or diddle the location output).

Essentially it is cheaper for them to make one chip that supports all the networks than to make a 4 custom chips for each network, and it is better for the end user, who can now use multiple networks to get a better/faster fix.

As a result almost all modern phones support GPS+Glonass, in fact a lot of mobiles use it without actually mentioning it (it just gets lumped into "GPS", or "Location" terms). I know my (relatively ancient) note 2 supports both, so I am sure all new phones do as well.

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Glowing dust doughnut circles white dwarf

Ogi

Re: This God geezer, he's been a busy lad

Paaah, a real god just sets the initial parameters of the universe, and lets it evolve to include what he wants in it :-) .

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Space fans eye launch of Lego Saturn V

Ogi

Re: Specialised Lego? James May.

To be fair, James May (and the rest of Top Gear) went a step further, and actually built a real life rocket and launched it. That was my favourite Top Gear Episode.

I still wish they would have another go at it, they came really close. Although, perhaps not based on the space shuttle launcher (which is not the best rocket design, due to the shuttle having to hang off its back rather than on top like other payloads).

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How much do containers thrash VMs in power usage? Thiiiis much

Ogi

And in other news....

An investigation into running a process in a container, vs running it as a user on the system directly, results in even lower power consumption.

It makes sense, because adding layers of abstraction reduces computational efficiency (more CPU cycles go to the system, vs the computation you want). It is the same reason some people forgo the OS and program the hardware directly, or even develop their own hardware (e.g. FPGAs).

The question is, whether the loss in computational efficiency is worth any benefits in management and automatic scaling out of resources. If you lose 20% of a nodes efficiency due to using virtualisation, but then you make it trivial to scale out to multiple nodes, then for some it is worth it (generally, Compute/electric power is cheaper than a persons time to manage it).

What the research does here, is give some numbers to the options, so people can actually work out whether it makes sense for them to go one way or another. It is useful to those who have to sit down and architect some large-scale infrastructure.

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Facebook CTO: Clear legal grounds needed for EU-US data exports

Ogi

Re: Schengen

I don't think the US would change at the behest of anyone external, including the EU. I would suspect more threats/arm-twisting/etc... until the EU concedes or waters down their demands.

Perhaps Facebook knows something we don't, or they are just eternally hopeful that things will somehow go back to how they were.

The cynic in me says they know something, multimillion dollar businesses don't sit and wait on a hope. They sit and wait for the tide to turn in their favour because they have information saying that it will happen.

Whether it actually does happen though, we shall see.

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Microsoft's OneDrive price hike has wrecked its cloud strategy

Ogi

Re: @Krillin reality check

"why would anyone keep a zombie in the garage?."

Well, to protect the NAS from looters of course!

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Ogi

Re: Coincidence?

Well yeah, if a bunch of people open accounts but end up never using the service, it will swing the average right down to something silly, like 5GB.

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Volkswagen: 800,000 of our cars may have cheated in CO2 tests

Ogi

Re: A German lawyer acquaintance with a BlueMotion Passat diesel...

I strongly suspect the German government would bail out VW. They bailed out the banks already , despite it being a bad idea economically, and not really benefiting the average person (in fact it harmed them, but that is a story for another time).

I would imagine that given the choice between printing some more Euro's and bailing out VW, or watching as Germany's biggest employer collapses (along with a lot of now disgruntled voters looking to blame someone for their woes, and more people on benefits), politicians will happily spend other peoples money just so the collapse doesn't happen on their watch.

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Raspberry Pi grows the pie with new deal allowing custom recipes

Ogi

I think Mini-ITX will be around for a long as it provides all the I/O connectors it does, without having everything go through USB.

I tried replacing some of my mini-itx systems with rasbPi's, but it didn't work out (specifically the file server. The early Pi just didn't have the grunt, the newer one does, but the USB kept conking out, giving out I/O errors once in a while, and the wifi card goes AWOL as well).

Media centre didn't work out either, as indexing all my music and videos would cause it to run out of RAM (but I have not tried the newer one, perhaps that will have the power), but for small light services, management of other computers, X terminals/display PC's, really really useful little things.

Not to mention RGB LED controllers (with presence sensing based on bluetooth address, so depending on who enters the room it sets their lighting preferences), and a lot of embedded stuff where a uC would be too fiddly or too restrictive to set up. A lovely little machine really, and a big thanks to the Pi Foundation for making it happen :-)

I personally find the two systems complimentary, and will probably continue to use them both in tamdem going forward :)

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Europe fails to ban web 'fast lanes' – what now for Euro net neutrality?

Ogi

Re: WANTED

Or build community wifi networks, like was done in the 2000's in Eastern Europe and other countries (where broadband was expensive and rare at first). Modern wifi kit is pretty damn fast (a lot faster than the 11/56mbit you'd get from 802.11b/g back then). Sure it might not compete with fibre to the premises, but it should be decent enough for general use. Then just link different local wifi networks with a VPN over standard internet (if people pooled together on the costs, you could get some pretty powerful pipe).

In EE people even made money off community wifi, some became wifi ISPs, and eventually moved into being normal ISPs. How it worked, is you would pay for the hardware (or buy it yourself), you would pay (one-off payment) to be connected to a nearby wifi AP, and then you could use the network unrestricted. After that you could pick an Internet gateway that resides on the network, pay a monthly fee like you normally would for internet, and then just set your default route to what they tell you.

Or build an encrypted overlay over the internet, like the I2P project. So you use the commercial infra, but as it is all encrypted, it is of little use to them for spying. I suspect the response would be to shove all encrypted comms to the lowest priority, but the multitude of businesses, or people working from home, etc... on VPNs would preclude it (I would hope).

If push comes to shove, there are still options, however still worth trying to stop them from their plans.

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Web giants, Sir Tim slam Europe's net neutrality rules on eve of vote

Ogi

Re: People who want to be politicians should not politicians.

If I remember my school classics correctly (It has been a long while, so apologies), the Ancient Greeks, when developing democracy, had two rules: One could not be a career politician, or a career orator (lawyer).

In court both sides had to represent themselves, one could ask someone else to represent you, but it must not be in exchange for payment of any kind. Plus said orator could not represent multiple people at once or in quick succession.

As for leaders, a citizen (rather than a slave) would be nominated for election. People would then vote from a list of nominees. This meant 3 core things:

1) The nominee lived in the society and were well integrated, so were relatively down to earth

2) You would have a pool of all people, including those who are not interested in seeking power for powers sake., to nominate from (unlinke now, where politicians are self selected for those who crave the power), and

3) Said nominee would have a business or job unrelated to their stint in politics/government, plus a social standing, that relied on the society continuing to function as well as before, or better

You would also go back to the society after your tenure, and if you did a lousy job it would be remembered by the rest, and would reflect on your social standing and family reputation. As such being chosen as leader was a privilege (if you do very well, it would increase your social standing in society), and a duty as a citizen to do a good job. It was seen as a necessary evil, rather than a career job for life kind of thing, as it is now.

Of course, the system is not without its problems, and you can argue whether it would scale to today's complex, global interconnected political societies, but even back then, thousands of years ago, the developers of democracy saw the inherent danger of politicians and lawyers to the system. Food for thought :-)

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Bug-hunt turns up vuln in LibreSSL

Ogi

Re: Loadable Microcode

Actually, thinking about it, perhaps some really really savvy hackers out there could actually make a microcode virus.

I would imagine it as a two part system (as microcode usually is loaded at boot, and wiped at power off), where the OS is infected, loads up the exploit microcode, which then sits and stays resident, making sure any attempts at OS cleanup fail (probably by just re-infecting it every time).

Essentially the two parts will make sure the other cannot be removed, until someone uses a liveCD to break the cycle and wipe the OS (assuming you could detect it in the first place).

I admit this is just out there, because I have no idea how microcode is structured, whether you can actually write programs in there (or is it just a translation table?) and how much space you have (although you can get 16MB cpu cache nowadays, which could fit the whole of win3.1 requirements with memory to spare), but an interesting idea none the less.

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Ogi

Plus, nowadays x86 CPUs are essentially RISC with a microcode translator on top. One advantage is that if a microcode bug is discovered (a-la FDIV bug), it doesn't render a bunch of CPUs broken. Instead the CPU manufacturer just issues a microcode update, which gets loaded into your CPU at boot, and life goes on as before.

So microcode/CPU errors, are rarely brought to the spotlight as much as before, nowadays people just patch their BIOS or download the new microcode and carry on, some may not even realise that their CPU has been updated.

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Terror in the Chernobyl dead zone: Life - of a wild kind - burgeons

Ogi

Re: Nuclear Power Generating

"Cars also kill birds and bats. Would you suggest taking up a bicycle as an alternative?"

I wouldn't, bicycles kill birds too*. In fact given a stupid/ill enough bird, any moving object will kill it. There is a difference between a moving object (which healthy birds/bats/etc... will notice and try to avoid), and something (like wind turbines) that causes a partial vaccuum to form in their wake, causing lung damage to said bird/bats. They can't see that, so can't avoid it.

Saying that, I think that is more a problem with the massive turbines and solar power stations. On a small, distributed setup, these things are less of a problem. Perhaps the idea then is lots of smaller, local power stations, rather than a few honking great massive ones? With base load supplied by Nuclear ideally (in my world at least)

*hit a bird in the face once on a downhill ride, thankfully I had a helmet with visor, but the bird didn't fare too well.

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Ogi

Re: Nuclear Power Generating

I keep thinking the best idea is to build more nuclear power plants in the contaminated zone.

I mean, the area is already contaminated, so it can't get much worse, you have all this idle land devoid of population, and (most likely) a country hungry for as much cheap clean energy as possible (including neighbours willing to buy it off you if the price is right). As there was a power plant there before you already have the infrastructure in place for power transmission (although it will most likely require a refurb), and no NIMBYs to protest and strangle the construction to the point where it becomes prohibitively expensive.

Better than building a nuclear power plant in another part of the country that is not contaminated, where even a minor radiation leak would register and cause problems.

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Apple 1 goes on sale, expected to fetch £300,000 to £500,000

Ogi

I would imagine at that age bitrot would be a problem, no?

I had that happen to a 286 motherboard that I kept in storage (it was new in box, only powered up upon purchase and kept as a spare for a production system). Powered it up a couple of years ago to find the BIOS chip was corrupted, and it could not finish POST.

Still looked brand new from factory though.

I would imagine that even if the apple was in perfect working order, it would not be bootable until the BIOS equivalent was reflashed.

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CompSci student arrested in Malaysia on doxing-for-ISIS charges

Ogi

"I love ISIS" picture on his fb profile?

Talk about painting a bullseye on yourself for law enforcement. Sounds like a fall guy for someone bigger, but that is just my opinion (I cannot imagine someone with high level hacking skills would advertise himself so).

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Dinosaur love hug: Dell's $64bn death pledge to EMC

Ogi

Re: your in-house sysadmin will provide you with better uptime than AWS?

Indeed, I too have seen some crazy uptimes on machines, some in the excess of 3000 days (old Sun SPARC hardware was bulletproof, I swear). The thing is, people who can build and run these systems so reliably commend high prices.

To play devils advocate for a minute, the thing about "The cloud". It is not only about the sharing of computing resources, but the sharing of skilled people.

Your average small firm with the local kid as a sysadmin is unlikely to manage these uptimes, nor to afford the people with the skills to do it. However if 100 such SMEs use the cloud, the cloud provider will have the cash around to hire the skilled people, who will then build and maintain a system to a high reliability, and all the SMEs will benefit.

Very large firms usually have enough money on hand to hire these people directly, so they don't need the cloud services (except to reduce capex in building datacentres or buying thousands of machines).

I suspect the future will see a mixed bag of cloud and non cloud. Yes, clouds have outages, but for a SME (especially if tech is not their primary focus) the question is "are those outages less frequent than before, when everything was done in house?". I suspect for many it is. Most firms would rather not have to bother having an IT person on hand at all, let alone run their own server room and manage all that. It is usually not their core business.

People who visit this site have the skills to build and maintain their own systems, so yeah for them the cloud does not bring much to the table (except security concerns, data leakage, and reliance on a third party), however I would say we are not the target market for this technology.

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BBC bypasses Linux kernel to make streaming videos flow

Ogi

Re: Moving out of the kernel to improve performance?

You are right, that the extent of ring involvement is dependant on the OS (it is also dependent on the CPU arch actually). Both Linux and Windows use two rings for kernel and userspace, not sure about the others (I remember hearing that openBSD uses all 4 of the x86 rings, but no idea if that is true).

I will admit, I was looking at this a while ago, when I implemented RDMA over Firewire as a poor mans Infiniband for clustering, but back then it was not possible to access the hardware from userspace, without essentially writing a shim kernel module that would sit and pass the needed data between kernel and user space, and therefore having the overheads I mentioned.

Now, that is Linux specific, however any monolithic kernel design by its nature has to have all userspace stuff go through the kernel. GNU Hurd goes to show that it is possible to have user-space device drivers without the overhead, but the kernel has to be designed for it.

The MMU is a hardware device (nowadays integrated in the CPU die) which handles memory translation on the low level. Not only is it already low latency, both the kernel and the userspace use it (all the time), so there is no difference between user/kernel space in this context. The difference is that userspace goes though an additional layer, the VMM (Virtual memory manager), so each process sees its own virtual address space. Only the kernel (that doesn't use the VMM) sees the real address space, and lacking in the extra indirection that the userspace has to travel, has a lower latency.

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Ogi

Re: Moving out of the kernel to improve performance?

"Also, given the right setup (e.g. CPU isolation and pinned execution threads to reserved CPUs) there is absolutely no reason for userspace code to be slower than kernel code (also no reason to be other way around, obviously); it is about cost of context switches (also cache hotness and similar things)"

Yes, the code execution speed kernel and userspace should be the same, after all, code is code, the CPU doesn't care. It is the transition overhead of switching between kernel/user space which slows things down, along with the switch between supervisor/user mode rings (if you are using a userspace device driver for instance, which is why they are less performant than kernel drivers) .

And yes, highly tuned systems can reduce latency, especially if in addition to pinned execution, you also pin interrupts to certain cores ( core 0, so that you don't route through LAPICs on most hardware, but at this level, your workload type and the actual x86 motherboard you buy makes a hell of a difference to latency, as they all route interrupts differently :-) )

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Ogi

Re: Moving out of the kernel to improve performance?

I don't think you are correct.

1. A userspace driver has to go through the kernel every time it tries to access the hardware, resulting in a context switch which slows things down compared to direct kernel access

2. A userspace program accessing hardware requires the kernel to drop into (and then out of) supervisor mode each time it does so, these switches in/out of that mode add additional latency compared to a kernel thread, which stays in supervisor mode

3. Userspace code never accesses RAM directly, it does it via the VMM, which itself uses the MMU for translation. The kernel does not use the VMM, so in theory it is a bit faster, but the primary benefit here is being able to directly get/access physical memory addresses, and for things like DMA.

Sure, machines may have gotten so fast that all the above is barely noticeable overhead in general use cases, but it doesn't mean said overhead doesn't exist.

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Ogi

Moving out of the kernel to improve performance?

I find that a distinctly odd occurrence. Historically things were put into the kernel because it was faster than userspace. So much faster that it was worth the programming difficulty, potential security holes and risk of locking up the system to do it for some things (excluding things like device drivers, which needed access to raw hardware and had to be in the kernel).

If anyone wanted performance above all else, they used to put it in the kernel. Is it really possible that Linux's network stack has become so inefficient and convoluted, that a userspace stack is actually magnitudes faster? That just sounds nuts. Admittedly the last time I had a good look at the network stack was in Linux 2.4 and early 2.6, so I might be out of date w.r.t the state of the art, but still, things in userspace being faster than kernel space just sounds wrong to me. Am I missing something?

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BT to shoot 'up to 330Mbps' G.fast into 2,000 Gosforth homes

Ogi

I no longer care one ioata about download speeds...

...as the offerings are fast enough for my needs. Give me some more symmetric lines. Some 200Mbit down, 10mbit up is really pointless, as I tend to saturate the outbound before the inbound reaches peak. Plus the ability to run my own cloud/services/etc... is really appealing.

Some are silly, like 50mbit down, 0.9mbit up. I even ask if they can offer something else, and they always say it isn't possible, unless you want to go leased line route. I don't need 1:1 contention, just more balanced down/up.

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Tesla X unfolds its Falcon wings, stumbles belatedly into the light

Ogi

Re: Door mirrors...

"The driver's side rear view mirror glass (just the glass oval) is over $800."

Damn... that sounds excessive. What on earth are you driving? And does that price include fitting?

The mirror glass for my cars costs in the range of $60-$250 new (the $250 is for special glass with the heaters and polarization and other fancy stuff).

I don't think I have ever seen $800 mirror glass (excluding fitting. Simple jobs can take a long time on modern cars, so I can imagine $800 if you include parts, labour and taxes).

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Ogi

"Until they become reasonably numerous, at which time governments will start to notice the amount of fuel duty they're losing. Thereafter electric power will be subject to a two-tier taxation regime similar to the one currently applied to diesel."

Nah, they will just start charging you by the miles driven. Works for all vehicles, regardless of method of energy delivery, and the charges can vary based on time of day and location.

Especially as the side effect is that they will have a legitimate reason for why they have to track the vehicle's every movement from when it is first registered on the roads, and for making it a criminal offence to disable tracking.

They would have a complete timestamped record of the vehicle location, speed, etc... and eventually will probably have access to any internal microphones/cames in the cockpit of these overly-computerised cars.

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Ogi

Re: Door mirrors...

"You have no stereo vision at the range of a car behind you. "

Not technically true. People instinctiely will bob their head about when looking at the mirror. This has the effect of increasing the parallax, allowing people to more accurately judge distances. Most people do this without noticing , but it is somethiing that cannot be done on a 2D screen.

It is also the trick people use with animated gifs, allowing you to perceive a 3D image in a 2D environment. (see here as an example: http://www.maddocman.com/wiggle-3d.htm Not my site, just the first on google search)

"The vision system can have distance measuring (Radar, lidar image processing) and can highlight cars in your blind spot"

So now we are replacing a cheap, simple and reliable system, with two complicated, computerized and expensive systems? And this is considered an improvement?

"If you have the screen anyway then the cost of the camera is negligble and less than the lifetime cost of fuel used by the extra drag."

Where would you put the screen? Most people look left when they want to manuveur left, having the screen in the centre would be worse than before. I would imagine there would need to be two screens (left and right, roughly where people now see their wing mirrors), in addition to whatever screens the rest of the car has.

"Wing mirrors also get broken and aren't replaced until the next MOT (or never over here) they are probably less reliable than cameras"

I disagree with that, I have rarely seen broken wing mirrors, most of them are really sturdy, you really need a lot of force to break them. I think less than 1% of the cars on the road I have seen had broken wing mirrors.

Not to mention a broken wing mirror is easily seen by others, so they can say "Ok, person might not be able to see me on that side of the car, better act accordingly". It acts as a visual sign. There is no way for other drivers to tell if the wing cameras are working or not, including police (who can pull you over if you have a broken wing mirror, at least here in the UK).

"Big advantage on no wing mirrors is reduced noise in the back"

From what I can see, replacing wing mirrors with cameras provides two minor advantages, while giving a boatload of disadvantages.

We are replacing a simple, reliable system, with two expensive, complicated less reliable systems, that will be:

a) more expensive to buy

b) more expensive to repair (coupled with others not being able to tell outside the car, less likely to get fixed unless it becomes an automatic MOT failure)

c) more dangerous (not only due to loss of ability to tell distance of car behind and because others can't tell if you can see them, but also because it is easier for cameras to be blinded by bright lights, or get dirty, or fail)

All for a minor gain in fuel economy, and less noise in the back? I would argue that as cars get more and more complicated, they last shorter periods of time. Pretty much the first things that go on second hand cars are the electrics. Engine/mechanicals are last, usually (unless you bought a pup that was badly treated).

As cars get more and more computerised and interconnected, they become so expensive to repair, that their lives will be shorter than the old cars. Some people already own a car only for the duration of the warranty, then sell it due to the expense (everyone complains about rip-off mechanics though, as if the job is easy and simple on new cars. It is ruddy awful working on new cars).

Cars like these will not last long, and will be scrapped and new ones built more often, becoming more like a consumer good rather than a durable good. This is a huge waste of energy IMO, which dwarfs whatever the fuel consumption improvement you would gain by getting rid of of the wing mirrors (especially as the drag can be reduced by smart aerodynamics, I seem to remember reading that some sports car actually had the wing mirrors improve downforce).

Really, complexity breeds problems and failures. It takes a lot of thinking and effort to make something simple, elegant and functional, along with an understanding the law of diminshing returns when it comes to application of technology.

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Ogi

Door mirrors...

"The Model X concept cars had cameras instead of door mirrors. This is a very sensible move in terms of fuel economy but unfortunately illegal as the world's car-industry regulation hasn’t caught up with technology."

My understanding is that it has less to do with slow regulation, than to do with the fact that rear cameras are just not as good as mirrors. Specifically you lose the 3D cues humans are used to that allow us to judge distances. Seeing a 2D representation on a screen of what is behind you will never be as good as a mirror (unless they develop a 3D display and camera set up, which will probably be a lot more expensive than a mirror).

Plus you would have to keep the displays running all the time so that you can do the "mirror-signal-maneuver", and there is a lot more that can go wrong with the system compared to a mirror (the only real failure mode is the mirror getting smashed)

Hence despite the fact that the tech is old(*) I don't think it will replace mirrors soon. After all, it hasn't replaced mirrors it in any other modern cars that I know of, especially as this is tech that can be retrofitted to ICE vechicles, and even there improvements in fuel economy are appreciated.

(*) I remember seeing some tuning houses in the 80's demo'ing rear view cameras with fat CRT screens in the dash instead of mirrors, not to mention that the late-90's and early 2000's "pimp my Vauxhall Astra" scene was full of LCDs and rear view cameras as well.

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BOFH: Power corrupts, uninterrupted power corrupts absolutely

Ogi

Re: Only me

I fully agree with you in the long term (the march of entropy and all that).

On a shorter term though, I would say LED Lighting is an example of a really low-efficiency heater. You would only get ~10% of the input energy out as heat :-)

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Twenty years since Windows 95, and we still love our Start buttons

Ogi

Re: The question of why the public accepted a substantial user interface change

Full win95 interface for Linux? Like fvwm95?

https://en.wikipedia.org/wiki/FVWM95

It was full enough for me to switch over non-techie users from win95 to Linux back in the day. I even used it on my old PDA as well.

Might actually install it now on my work desktop, just to go totally retro in the office (I might still have some of the old win95/98 wallpapers somewhere as well)

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Vodafone adopts hydrogen fuel cells to dodge African outages

Ogi

Re: but with an eye to CO2 emissions Vodafone is keen to reduce the use of diesel.

"Solar panels would have to be transported by vehicle as well, you know. "

Yes, but only once. You need to keep sending fuel (whether it be hydrogen or diesel) to these remote places, most likely by vehicle of some sort. Yes, you will need to have someone come round and clean the panels, but that is less often than having to restock the fuel. Probably can be done as part of the general maintenance that is already being done on the installed equipment..

"The nice thing with hydrogen is that you can ALSO produce it cleanly if you wish. It's not a fuel SOURCE, it's an energy STORE."

Same thing applies to liquid fuel, with the bonus of being easier to store and transport. Liquid fuels like Alcohol, Petrol, Diesel, etc... are essentially hydrogen fuel with carbon atoms binding it. Hence the term "hydro-carbon" :)

Indeed the first combustion engines ran on renewable fuel. Early internal combustion engines ran on coal gas. Otto's 4-stroke was alcohol fuelled, while Diesels engine ran on veg oil. The only reason we use fossil fuels is because it is cheaper to dig it out the ground then it is to produce it cleanly.

I remember reading somewhere that the raw cost of refined petrol (minus all the taxes, and profits, etc...) would have to hit 95pence/L before it becomes viable to mass produce it(*) cleanly rather than dig it out. Currently the raw cost of pumping and refining oil into petrol is about 2-3pence/L.

(*) by "it" I mean a clean renewable fuel that can burn in petrol engines. It can be a 1-1 replacement like Butanol, or Alcohol fuel (which would need modifications to existing engines).

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Eyes on the prize: Ten 23-24-inch monitors for under £150

Ogi

Well, I see I was wrong in how this all works, so I've withdrawn my original comment. Thanks a lot guys, your posts were all really insightful for me. Upvotes all round! :)

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Ogi

How would they know that you connected it to an aerial then? I mean, they get your details from the retailer, and you just show/tell them you didn't connect it up. What stops you just connecting it up once they leave? It isn't like they can monitor the back of the TV 24/7. If that is true, it seems like a really massive loophole in the whole thing.

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Ogi

I only know because years ago, when I decided to ditch watching TV, I had to deal with the TV licensing guys. Their argument was because I bought a "TV" that had a receiver (i.e. the "capability to receive broadcast TV"), I intended to use it to receive broadcast TV and have to pay the TV licence.

I guess it makes sense, otherwise anybody could just buy a TV, not pay the licence by claiming "Look! I don't intend to watch broadcast TV. I did not hook it up to an antenna" and then just plug it in when the TV licensing guys go away.

In the end, I took a Dremel to my TV's tuner to physically turn it into a dumb monitor (it has spent its entire time hooked up to my PC, or my XBMC setup), which satisfied them, and since then they have not bothered me.

I mean, yes, I could go to court and argue about what I want to do, why I don't need to pay the licence, and the precise meaning of "Intent" in this context, but it was simpler, faster, less stressful and cheaper to just disable the tuner in my TV.

Although I seem to remember them thinking of widening the licensing scope to include any internet connected computer which is capable of watching live streaming of Iplayer. Not sure if that will get through though, we will see.

I guess it depends on who you get from the TV licensing people, and how anal they are. At least this way they can't come back later and say I lied to them. The TV is no longer a TV according to their own definition.

IANAL and all that, just saying what I had to do to get them off my back :-)

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RELICS of the Earth's long lost TWIN planet FOUND ON MOON

Ogi

Re: Say what?

Indeed, I've never heard a hypothesis that stated the body that collided with Earth to form the moon was from "far away". In fact the general assumption was that Theia formed very near to earth's orbit, hence the two bodies orbits being able to be perturbed enough to eventually collide.

I remember many years ago watching a BBC program (Horizon?) that pretty much said this much, including stating that moon rocks collected from the Apollo missions pretty much confirmed this. As such I assumed that "A sister planet collided with Earth to form moon" was the prevailing theory we had for a while now.

While more evidence is always great in science, I don't think this is as game changing as the article makes it out to be.

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