* Posts by Nigel 11

3206 posts • joined 10 Jun 2009

AMD ships first Fusion processors

Nigel 11
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Netbook on a chip?

9W, 18W is netbook territory. If they signifcantly outperform Intel's Atoms (especially on graphics) then they might be the key to getting acceptable performance on a Netbook running Windows 7.

Small biz doubts red tape claims

Nigel 11

An idea

The government should have an independant agency that estimates the time and cost of completing every form that the government creates. Further, there should be an appeals procedure through which a business can claim compensation if it can show the estimate to be grossly inaccurate.

The governmeent and its civil servants will then be unable to claim that they don't know the cost of their red tape, and cost-benefit analysis will be possible. It'll still be their benefit, our cost ... but at least there will be a reasonable factual basis for argument.

WD and Xyratex discuss future tech roadmap for disk drives

Nigel 11

Big drives not *always* needed.

You're right that the desktop of the near will be better equipped with an 80Gb SSD not a 250Gb HD. Hard disk manufacturers can see this coming. If the hard disk is to have any future, it's at the high-capacity end of the market.

As for who needs (say) 100Tb drives ... if they were on the market today at £100 each, we'd be buying. Give our researchers any amount of CPU power and storage, and they'll fill it to capacity within a few weeks. Molecular modelling, if you were wondering. Others I know something about the IT needs: particle physicists, astronomers, DNA, Oil prospecting. Doubtless lots of other things that I've never found out about.

Linux life savers for paranoid penguins

Nigel 11

Drop a PDP11 ...

... off the tailgate of the delivery lorry!

Luckily it was brand new so no data loss, and DEC's insurers dealt with the rest. Happy days.

USB fanboys teased with 16-port hub

Nigel 11

Not utterly bonkers

Sensible uses I can think of:

Batch-duplicating USB data sticks.

Uploading data from multiple devices, for example portable standalone barcode scanners

Testing software RAID with 16-disk configurations (where the disks are probably memory sticks)

Or even just as a charging station for umpteen USB-chargeable devices. I've got an 8-port USB hub doing just this. The hub has never been connected to a computer, just to its mains "brick".

Does seem a bit pricey, though. One can get three six-port hubs for considerably less.

Netbooks: notebook evolved - or stunted throwback?

Nigel 11
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Just a cheap notebook

Not a stunted throwback nor revolutionary - just a boring cheap notebook for use on-the-move.

Many of our staff have a netbook for giving presentations and network browsing away from home. They're adequate. They're cheap enough to throw in a case or bag without worrying too much about breaking it or losing it, and they are less heavy than a standard notebook.

The remarkably simple formula for success: just about fast enough, low cost, light weight and decent battery life.

Sales dropping? I'm not surprised, everyone who wants one has got one. Also they aren't really adequate for Windows 7 but you can't get XP unless you retro-install it on a corporate license. Intel will probably ship an Atom fast enough for "7" soon and then the market might pick up a bit.

Aircraft bombs may mean end to in-flight Wi-Fi, mobile

Nigel 11

Terrorist would prefer a phone bomb

A phone bomb can be detonated when it will cause most damage on the ground, for example during low-altitude approach to an airport over an urban area.

Nigel 11

Cloning - not a big problem

Someone has to be *on the plane* to register the phone with the clone. So he's still a suicide bomber, albeit with a remote-control bomb in hold baggage now under someone else's control. I thought the big worry was a phone-bomb loaded as *freight*, and a non-suicide-bomber able to detonate it from the ground. (Possibly also GPS-track it).

You could also make my plane-cell base station de-register any phone as soon as it is turned off. Don't know how phones work well enough to say if a phone and its clone both on at the same time could be detected. I'd hope so, if only as some sort of unusual protocol error which would be reason enough to immediately deregister both the phone and its clone.

And as someone suggested above, phone-suppressors in the hold, faraday-shielded from the cabin by the metal floor, sounds like such a good idea they ought ti implement it immediately. If cabin floors are not solid metal, then they should henceforward be designed with a metal foil screen (which could be retrofitted during maintenance).

Nigel 11

An idea

It ought to be possible to design an airliner cell, which doesn't connect to any phone that hasn't been explicitly registered. Registration could be self-service. After the flight takes off, a passenger wanting to use his or her phone turns it on and takes to the registration point. This would be a metal box (faraday cage, radio screen) which reads the phone's ID from inside, once the box's door is closed. Once registered, the phone would work normally from any seat in the cabin, but (automatically) only until the plane next landed.

So any passenger on the plane could use their phone, but a phone in the luggage compartment would be unable to register itself even it it had been cunningly reprogrammed to try. Wouldn't stop suicide bombers, but would defeat the non-suicide variety (or at least force them to use less precise triggering devices such as timers or air pressure switches).

Wi-fi notebooks, effectvely ditto.

DWP CTO predicts the end of Windows

Nigel 11

Not running LInux then

""It takes that long for a desktop operating environment to get so long in the tooth that no matter what you do you can't keep it going any longer. And we'll keep it that long because the costs of getting a working desktop in the first place are so absurdly high that doing anything else is completely irresponsible,"

What he means, is it takes that long for Microsoft to launch the replacement, to issue the final service pack, to issue a number of security patches some of which appear designed to degrade your systems' performance, to cease all support, and finally for someone to "discover" a still-unfixed and now unfixable day-zero bug.

If it were open source you could keep it running for as long as you wanted to.

If the files it processed were all fully open standards then there really wouldn't be an issue about whether you used a decades-old desktop or the very latest one. It's only Microsoft that hardwires the file format to the processing program to the desktop O/S, for their own commercial gain and everyone else's pain.

(Not sure if it's relevant, but I recently booted Win 98 SE in a VM under Linux. Took all of two seconds to boot and was a vastly more responsive environment than Win 7 native on the same hardware.)

ZTE calls foul over senators' 'xenophobic' letter

Nigel 11

The biter bit?

Well, clearly both the USA and the Chinese have learned from the back-doors which Microsoft once shipped (and for all we know still ship? ) with Windoze.

The right non-protectionist answer would be to insist on open source, complete with everything necessary to compile it from the source, as shipped or with patches. (And of course, manufacturer patches to be supplied as source). As long as someone actually vets the source and rebuilds the binaries, there's far less likelyhood of anything nasty lurking therein.

Which just leaves the problem that these days it's quite feasible to implement secret backdoors in the hardware itself.

Rocks, hard places and Congo minerals

Nigel 11

Slave labour?

Probably not the only reason. They'd have to have good ores as well.

Simple economics: if someone paid x can mine quantity y in one shift, and someone paid 10x can mine 11y in one shift, then the men earning 10x can put the other mine out of business. (All other factors being equal of course). Higher productivity relates strongly to ore richness and to how much other rock has to be removed to get at the ore, although high-quality mechanisation and automation can also be significant.. For bulk materials like iron or copper ore, transport costs are very significant, but for small amounts of valuable product, they're not.

Nigel 11

Just in case

Just in case, does "scrap tin" originating from the DRC have a different isotopic fingerprint of its valuable impurities compared to ores from other parts of the world? A smuggler would find it quite easy to change the Ta:Nb ratio or other elemental ratios, but if the ratios of the isotopes of these two elements fingerprinted the metal, it would be far harder to disguise where it came from.

I'm guessing not - with the exceptions of materials originating in radioactive decay and materials of biological origin, isotopic ratios are pretty close to globaly constant because the chemistry (especially of heavy elements) is not isotope-sensitive.

Storage startup busts object location barrier

Nigel 11

Testing 10,000 nodes

They could run 10 VM instances per physical node. Of course that'll introduce inefficiency, but it should be just a constant VM overhead, and will let them see if anything breaks down or scales badly.

Microsoft holds Androids hostage in open source wars

Nigel 11

Salary premium

There are two reasons why a job may command a salary premium.

#1 the number of vacancies is growing faster than the number of people with the skillset.

#2 the job is so crap that people with the skillset choose to do something else unless paid extra.

Nuff said.

First tube station to get Wi-Fi next week

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Wi-fi bombs

I don't like the idea of a bomb on the tube with an internet presence. Just as much a bad idea as enabllng mobile phones down there. There is a more restricted supply of suicide bombers than the other sort.

They'll spend a fortune on rolling this out, and then they'll have to turn it off. Please, spend the money on sorting out the trains and signals instead, so we can get to our destinations more reliably and with less chance of being blown to pieces by a madman.

Highest point on the Moon found: Higher than Mount Everest

Nigel 11

Exactly what you'd expect

Firstly, lunar gravity is 1/6 of the Earth's, so there's less downforce trying to flatten out a lunar mountain.

Secondly, the moon is a lot less hot inside than the Earth. Here, solid rock gives way to stuff with the consistency of toffee a few tens of miles down. Mountains melt from the bottom up over geological time (like icebergs, but slower). On the moon it's hard rock a lot further down (all the way? )

If they'd found that the Earth was wrinklier than the Moon, it would have been interesting.

Boffins mount campaign against France's official kilogramme

Nigel 11

Another subtlety

Another subtlety is whether gravitational mass (commonly known as weight) is the same as inertial mass. It's been shown to very high accuracy that the two are equivalent for everyday forms of matter. But is the inertial mass of a kilogramme of electrons the same as that of a kilogramme of protons or a kilogramme of neutrons?

Nigel 11

Register unit of Mass

Isn't the Pound (1 lb) odd enough, considered along with its siblings: grains, ounces, stones, hundredweights, tons, and you really don't want to know about its cousins. Oh, you do? Well google "Imperial Units of weight"

The centihundredweight (or cCwt?) might be amusing: cancelling, you get exactly one weight. (1 wt.)

In passing, why do the French use tonnes, when clearly they ought to use megagrammes?

Equality Act causes logistics nightmare

Nigel 11

Bad for black males and white females?

If they aren't careful they'll create the situation where anyone who is in one minority group will always lose out to someone who is in two. So black males will lose out to black females, gays will lose out to disabled gays, and so on. Not so much out of prejudice, but because few organisations have anyone working in HR who understands how to do multivariate statistics properly!

The road to hell is paved with good intentions.

Keep your PC clean - or we'll shut you down

Nigel 11

Visa sux

The second time I ran into Vilified by Visa, I applied for a Mastercard. When I got it I chopped up the Visa card.

Since then Mastercard has gone some distance down the same dead end, but at least their equally pointless system "works" and is at least as fast as the sites I am ordering from.

Nigel 11

You can't

You can't require that.

What you can permit or require is for the customer to clear up the mess once he is made aware of it, and to permit disconnecting him until he does.

Just like MoT testing cars. It's not an offense to drive a car that will fail its MoT in to a testing station. But when it fails, there is an obligation on its owner to get it repaired and re-tested (or scrapped)

Nigel 11

Requiring you to be a responsible adult?

Cutting off someone whose computer is being used as a host by virii and criminal third parties isn't treating the owner as a criminal. It's just forcing him to do what he ought to want to do if he's a responsible adult who is made aware of the problem with his system.

The obvious precedent is the MoT test for cars. You are not allowed to drive around in an untested vehicle, or in one that has tested unsafe. That's because it's not just yourself that you are putting at risk, it's also everyone else on the roads and pavements. Likewise, unsafe computers on the information superhighway.

The thing that worries me is who sets the standards. I'm quite certain that Microsoft is planning to sneak something in, which the open source community cannot comply with. "Must have working X", where X is proprietary Microsoft technology. A car equivalent might be requiring all cars to have a working petrol-vapour recovery system ... including diesel, LPG and electric ones!

Cameron: Carriers tomorrow, bombers today

Nigel 11


You'll notice that one thing the UK isn't cutting is its submarine fleet. I'm sure that any warmongers in Argentina have taken note, and don't have an answer.

Personally, I'm not convinced that warships are viable in today's world. Too vulnerable to attack by missile from above, and by torpedo from below.

Apple squashes unauthorized MacBook battery maker

Nigel 11
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Difference beteween patent and copyright?

In the UK there was a lawsuit which established the right to manufacture replacement exhaust pipes which appeared to be exact copies of the manufacturer's original. The ruling was that if the shape of the car body dictated the shape of the exhaust pipe leaving no free choices, then the "copy" did not breach copyright. Minor differences such as the position of welded joints and the internal structure of the baffles proved that it was not a copy, just a re-implemetation.

However, exhaust pipe connectors are not patented. Maybe it's different for a patented electrical connector - the owner of the patent has a monopoly on its manufacture, and is not obliged to sell the connector to anyone else at a reasonable price or even at any price? That obligation or lack thereof would be addressed under monopoly regulation.

Personally I'd have thought a magnetic electrical connector trivial, and therefore unpatentable. But you'd have to pay so much to lawyers to bust the patent, it wouldn't be worth trying. There's a market opportunity here for a small start-up limited company. Just sell the things and pay yourself and your workers a salary. (Preferably, by mail order from, say, China). If Apple sue and you go bust, you've lost nothing much. Let them play whack-a-mole!

Iomega's flashy SSD clones your PC

Nigel 11

Back to front?

Surely you want the SSD on the inside of the PC, to hold the O/S and software for rapid booting and loading? If one needs to store many gigabytes, they can go on a USB or (E)SATA disk drive inside or outside the PC, with an external HDD for backup.

Of course, Win 7 is so excessively bloated, that an internal SSD has to be rather large and therefore still rather expensive. Sigh.

WD thrusts forth its mighty 3TB internal hardness

Nigel 11

What's the low-down for Linux on curent PCs?

Anyone know for sure what the siutuation is for Linux users, where Linux is running on a PC with an old-style BIOS?

Seagate's shrinks GoFlex drive

Nigel 11

Not backup quality?

There seems to be a developing trend for manufacturers to sell their latest drives in consumer USB disk packages before shipping them as internal drives. Might this be a sort of post-beta testing, on people who are much less likely to sue if the bleeding-edge tech proves less than perfectly reliable?

Anyway, my warning is that "random" USB drives are not a good choice for backing up important data. Build your own using a marketed internal SATA drive with a 3 or 5 year warranty and a USB enclosure. Better still don't risk your data through a cheap "random" SATA to USB chip. Use E-SATA, or a SATA drive in a swappable caddy.

OOo's put the willies up Microsoft

Nigel 11

Dated and slightly clunky UI?

You could say that about the pedals and big wheel that we all use to control our cars. But no-one would seriously *dream* of changing that interface. There would be fatal consequences if they did.

After one has used an interface lots, it gets patterned into the non-conscious parts of our brains, so that conscious thoughts can concentrate on *what* I am creating, and the unconscious deals with the details of formatting etc. This is why I loathe and detest Microsoft's continuous and gratuitous invention of new interfaces, without even offering a "classic interface" option. Openoffice has so far left the interface alone, and I sincerely hope that they continue to do so.

In my book, the only interface that ever needs changes that are not backwards-compatible, is the one that is immediately hated by new users, and which continues to be hated after climbing its learning curve. Menus are an extremely good way of making it possible to insert new features without confusing the heck out of experienced users of the old features.

DIY cloud box Pogoplug gets integrated wireless

Nigel 11

What I wish for

I really wish that they'd ship one of these beasties, or something like it, with SVGA graphics and a decent chunk of RAM. Then as well as being a home fileserver, it could be an always-on web-access point, meaning that a lot of the time you'd not need to boot the "real" computer at all.

And/or give it an ADSL port or a second Ethernet port, because Linux is quite capable of being your router. Or the other way around, add USB2 ports and VGA to a Linux-based wireless router so no-one needs a PogoPlug.

Hefty physicist: Global warming is 'pseudoscientific fraud'

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Not much of a physicist

The one thing about global warming that is established beyond reasonable doubt, and which can be confirmed using completely controlled laboratory physics experiments in quantitative detail, is the physics. Greenhouse gases (CO2, CH4, not to forget H2O) DO trap solar radiation within the Earth's atmosphere. Indeed, the Earth would be almost uninhabitable were it not for this effect - its black-body equilibrium temperature is only marginally above freezing, the greenhouse effect is the reason it is comfortable.

What is happening or might happen to the Earth's climate as a result of the human race adding more CO2 and CH4 on top of the natural levels is still very open to debate, but it's also not physics.

Given the lack of alternative Earths for us to live on should this global experiment go badly, I believe that it' s only sensible to err on the side of caution! Which sadly, we aren't.

Ballmer goes to LSE as internal doc calls for radical overhaul of MS

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Re; Re: Except that ...

If you can't find out what OS it's running, you can't *begin* to tell whether it crashed because of hardware failing underneath it, or the application code that you interface to failing (leaving a perfectly functioning O/S lacking any input device to tell it to abort the application).

If it's displaying BSOD or Linux oops screens, you can rule out the app, but faulty hardware may well be to blame.If you've got two of them with identical firmware and only one is unreliable, it almost certainly is the hardware at fault.

Still, there are a lot of routers, PVRs and suchlike running LInux. If there is any router that runs embedded Windoze, I've never heard of it (and frankly, if I had heard of it, that would be a reason I wouldn't buy it! ). Why would anyone pay good money to Microsoft for an inefficient, bloated, x86-only, closed-source, programmer-hostile O/S, when you can have Linux for free?

Youth jailed for not handing over encryption password

Nigel 11

Refused, not forgotten

The chap we are discussing "refused" to provide his password. I'm assuming that meant he said "No" rather than "I've forgotten it". The latter would have been a smarter answer and I'd hope it would lead to an acquittal - how can the prosecution possibly prove beyond reasonable doubt that this is not the truth? If it really is illegal to forget, I'd expect a jury nullification, or a successful appeal to the EU court of himan rights.

I agree that the whole concept is stupid. Anyone competent with something to hide will combine steganography and plausible deniability (multiple encrypted volumes in one hidden container, one or two innocuous volumes that you're happy to reveal if they can work out where they are hiding, using software that always creates large amounts of random padding so they can't hope to prove that you're concealing more than you've shown them).

Nigel 11

Other safeguards

I'm not sure that there should be an absolute right to hide behind unbreakable encryption. One doesn't have a similar right with respect to paper documents. Provided the police have obtained a search warrant, they can legally break any physical lock if you won't provide them with the key. (There's no such thing as an unbreakable lock or safe).

Do the police have to obtain a search warrant for your computer, before they can order you to decrypt? If so, that appears to be an appropriate safeguard, and an exact analogue to what has been the case for paperwork for many years.

If they don't have to obtain a search warrant, then they should be required to.

There should probably also be a provision that evidence obtained by requiring one to decrypt should be admissible only if it confirms the suspicions that led to the warrant being granted. In other words, if they are investigating money-laundering and they find only porn, they should not be able to charge one with posession thereof, because the grounds for the warrant have been proved false.

Legendary steampunk computer 'should be built' - programmer

Nigel 11


In fiction, the Nazis did continue that development. Charles Stross, "The Atrocity Archives".

Where's the Cthulu icon? (though Stross is both scarier and funnier).

Nigel 11

Why do it the wrong way?

There are at least two better ways to build a non-electronic computer using principles that were understood in the middle 1800s. It's a huge shame that Babbage never encountered them.

The first is electromagnetism. Use relays. I don't think they'd been invented, but I'm sure if you'd asked a young Faraday how to turn an electric current on or off using another electric current, he'd have invented the relay in minutes. Anything binary that can be done with a transistor can be done with a relay. Don't know if a stored-program computer has ever been built out of relays, but complicated logic often still is. That's because relays have quite enormous noise immunity and can be designed to fail safe. Good characteristics for (say) safety interlock systems in a nuclear power station.

The second is fluidics/ pneumatic logic. Logic gates and binary storage can both be created out of streams of compressed air (or water), rather than streams of electrons. For a fun application, look up the water computer that someone built at MIT. I believe that a compressed air computer has actually been used inside a jet engine (probably in the days of Germanium transistors which couldn't hack hot places).

Note: a clock rate of many kilohertz should be achievable. Practical note: one could give such a beast keyboard input (like an organ, but with more complex pipework). Aesthetic note: a factor of two is an octave, threes give perfect fifths, fives give major thirds. Some algorithms might sound quite pleasant as they crunched. Anyone fancy writing a simulator including audio?

London Transport plans Oyster bypass

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Isn't it bleeding obvious ...

London transport is BIGGER than any other European city transport system! Even if you amputated the bits outside Zone 6, it's still something like 30 miles diameter.

And in any case it would be nice to have the system rolled out further afield rather than hamstrung by a fixed fare. Don't they have things like Oyster in the Netherlands that are valid anywhere in the country for travel to anywhere else?

Western Digital gearing up to sell 3TB drives

Nigel 11

Software problem

There's a software problem for internal drives bigger than 2Tb, in that the classic partition table can't describe a drive bigger than 2Tb. I expect this will seriously hold back the availability of monster internal drives, because the manufacturers and distributors will be scared of a vast number of product returns from Joes who don't understand this issue or what to do about it.

(Sigh) Why didn't they migrate to an extended partition table format as soon as drives were big enough that losing a few kilobytes wasn't a significant loss? By now it would have become the default for everything, and there would be no problem at all.

(Suggestion) they could hard-partition the drive into two sub-2Tb zones, using two SATA LUNs, as a jumper-selected option. Linux would grok that without any difficulty. Windows ?... couldn't care less.

Best Buys: Budget Mono Laser Printers

Nigel 11


Cheap printers all use the Gillette model - sell the printer at or below cost, make the profit on the consumables. Also be warned that some manufacturers deliberately "churn" their models, so that as soon as there's a new model on the market that takes a different design of toner, the price of toner for the old model can be increased without upsetting any product reviewers.

Be very sure how many pages you are going to print. In general it's better to spend more on a printer with a lower running cost. Unless you *really* want a tiny increase in B&W print quality, I wouldn't buy any of these. I'd buy an HP Officejet Pro 8000 for about the same after cashback, with colour printing, duplex ability, and a lower cost per page from XL ink cartridges.

OpenOffice files Oracle divorce papers

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What about "Easy" then?

Stelios can't trademark "Easy", but it doesn't stop him setting his lawyers on anyone who dares to trade as Easy anything. Not even if they were trading before EasyJet existed.

It costs money to defend a trademark against an infringement accusation. Money that a free project either doesn't have, or can better spend on other things.

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Suggest a better name!

It says in the article, it's a temporary name.

"Office Libre" would be better, but perhaps vulnerable to a lawsuit from Microsoft. Which is probably the key. Now the project is out from under the corporate lawyer-shelter that was provided by Sun, it will have to tread much more carefully.

My guess is that the placeholder may have to be replaced by something not containing "Office" at all.

I'll start the suggestions ball rolling with "FreeDoc". At least it trips off the tongue OK.

Baby Boomers committing suicide at unprecedented rates

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Could it be the drugs?

Might it be something to do with the widespread use of recreational psychoactive drugs? Maybe one or more of the common "recreational" drugs are to one's long-term mental health, what asbestos is to one's long-term lung health.

Or even medicaly prescribed psychoactives? I read somewhere once, that one in three of the USA middle classes are on some form of psychoactive medication. I found that quite scary (if true).

Beer - tried and tested for millennia, safe for most of us. (Moderate drinking raises life expectancy).

Nutter repairmen scale 1,768ft TV mast

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Not necessarily fatal

There is a club that you can join only if you have survived exiting from an aeroplane in flight without a working parachute. There are surprisingly many members.

From memory, the record is falling about 40,000 feet. It's what you land on that matters. The side of a pine tree and thence into a deep snowdrift is a good recipe.

Then there's the Czech woman who jumped off the top of her tower block when she found out that her husband was having an affair. Guess who she landed on? She survived. He didn't.

How do you copy 60m files?

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Wrong ... you mean, it's running Windoze.

"Not easy once you try doing a file transfer via rsync through an ssh tunnel, like your suggesting, but the destination server isn't running an ssh server....let alone use / as a path convention."

Well, if the target system is running LInux, then turn on its sshd service!

If it's running Windoze ... well, borrow another PC, boot an appropriate Linux live CD, mount the MS Shared folder as CIFS, start the ssh daemon, and rsync through the temporary Linux system to the MS system.

Linux: the system that provides answers and encourages creativity.

Windoze: the system that erects obstacles and encourages stupidity.

Intel eats crow on software RAID

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You mean, like everyone running Linux ran out and purchased a SCO license? Not.

They'd have to say what it is that they claim a patent on. (SCO tried not to, basically because they were bluffing, and the FUD didn't work). Then it's extremely likely that someone will show the prior art, or the community will have replaced the patented bit with some other sort of wheel in the next release.

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Six is standard, and you can do 6 x 8 with LUNs

Six IS standard, isn't it? At least in the chipsets ... some cheapo motherboards save money by connecing up less of them.

I've never tried them, but I've read about SATA LUN boards. It's a little board that fans out one SATA cable to four or eight disks. No bus interface. SATA is logically like the old SCSI bus, and can support many disks on a single port, if your O/S understands what it's seeing. I read about building a Linux system with 48 SATA disks connected to a standard motherboard once.

Nigel 11

RAID-5 numbers

I've done a RAID-5 reconstruct on a Linux software MD raid array of six SATA drives (on an AMD motherboard chipset). All the drives maxed out at about 150Mb/s (reading from 5, writing XOR to the 6th, with the checksum data write rotating around all the disks in the usual way). That was on a system with a 45W Athlon II AM2+ CPU, and it had plenty of CPU cycles to spare while this was going on.

Kind of puts that 3Ware card in perspective.

On most workloads it's academic anyway. The disks spend most of their time seeking. The I/O data rate is nowhere near the maximim sustainable rate. Reconstruct (on an otherwise idle system) is the most I/O and checksum-calculation it'll ever do. BTW Linux reconstruct is smart, it'll throttle the reconstruction IO rate if the system gets busy, rather than slow the real work down unacceptably.

A 3Ware horror story from long ago. I used to use them, back in the days when hardware RAID really was faster. One day an engineer connected the wrong cables to the drives and the controller trashed the array. Shouldn't have happened. But I do know for sure, on Linux you don't have to bother labelling the cables, because Linux reads the disks to ID the array components. It doesn't matter in the slightest if the disks have been shuffled between shutdown and startup.

BTW Yes, it'll boot off shuffled disks, as long as /boot is a 6-way mirror partition and you've remembered to duplicate the MBR onto all 6 disks.

Nigel 11
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Software RAID rules

This isn't news to anyone that runs Linux. Software RAID has been trouncing RAID controllers for several years. The overhead is negligible and you get lots of nice features like dynamic resizing and re-shaping of arrays (powerfail-safe ... not an experiment I've tried!) It's only Windoze that needs the band-aids of hardware RAID or FakeRAID, because it's crap.

In fact the CPU overhead has been unimportant since Pentium-4 days. The penalty was having to do two reads and a write per RAID-write along a PCI bus, compared to just one write for a hardware RAID controller. That penalty went away with modern multi-SATA chipsets and PCI-express. You can max out six HDDs on an intel ICHx doing a RAID rebuild, the disks are the bottleneck.

The future trend will be to remove RAID from the disk block driver or controller, and embed it into the filesystem, along with data-checksumming so that the filesystem can detect (and possibly repair) various sorts of higher-level errors. It also becomes possible to decide on a per-file basis whether to use no RAID, mirror-RAID, RAID-5 or -6. BTRFS is coming. (Agreed, ZFS was there first, shame about the licensing).

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You do really want to use ECC RAM

I've seen what slightly faulty RAM can do to a filesystem, and it wasn't pretty. The same on RAID-5 could be far worse, if a disk failed and you tried to reconstruct through failing RAM.

So any RAID-5 system should use ECC RAM. This ought to be a selling point for hardware RAID controller manufacturers ... but I'm not aware of any of the low-end ones (4-8 disk) that actually use ECC!

Intel don't support ECC on any "desktop" boards and CPUs, you have to buy an expensive server board and Xeon. If you want to do it at home, build your own system with an AMD CPU, ECC RAM, and a motherboard that supports ECC (Most, not all, ASUS ones do). The 45 Watt TDP low-end CPUs are plenty fast enough for a fileserver box, and run cooler and quieter.

Intel - if you are serious about Atom servers in the datacentre, they need ECC support!!

Linus Torvalds outs himself as US citizen

Nigel 11

Did you mean what that quote implies?

"Torvalds stands on the shoulders of giants."

Newton said of himself, that if he had seen further than other men, it was because he stood on the shoulders of giants. It's true of virtualy all progress, probably ever since someone first mastered fire or manufactured a stone tool.

I very much doubt Linus would deny it. Nevertheless, it was Linus started this ball rolling, and it's turned out to be a pretty darned important ball.

Linus has published his own justifications for GPL V2 vs V3. They're well argued. There's the pragmatic one, that it would be just too hard to track down every contributor and get them to agree to re-license under GPL V3. Or, to re-write all the code that couldn't be reassigned. And the philosophical one. Linus doesn't agree with the GPL V3, he prefers BSD-type licenses.

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