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Comment Re:"Systemd developers have rejected ..." (Score 1) 697

UEFI is accessible for change. Note the standard doesn't demand that 'getting bricked' be possible, it's the firmware developer implementations that have issues.

Right now the efi variables are normal files: $ ls /sys/firmware/efi/efivars/Boot0000-8be4df61-93ca-11d2-aa0d-00e098032b8c -l -rw-r--r-- 1 root root 57 Jan 22 09:58 /sys/firmware/efi/efivars/Boot0000-8be4df61-93ca-11d2-aa0d-00e098032b8c

Thanks, I've not paid enough attention to this, I'm glad it didn't catch me.

So my proposal would be either to make each something like a character device, with special ioctl for 'deletion', or a normal file, except ignore 'unlink()' and provide a separate character device with ioctl to remove the variables, or some 'echo delete Boot000 > whatever' type interface. The latter is probably the best all things considered.

It seems reasonable, especially as it would offer a degree of protection against shitty UEFI implementations.

The whole acess to the variables space is already an abstraction, so efivars can do whatever they want (though would break downstream utilit(ies) expecting to be able to unlink, but I think that's worth the work. A utility can be backward compatible by checking for existence of new interface, and falling back to unlink should that new remove interface be missing.

Indeed, breaking a few utilities is a small price to pay so you can't brick a motherboard. Software can change.

Comment Re:Not at all (Score 1) 151

I think we are talking about different scenarios. I appreciate the description of your locale, mine is different.

cats didn't suddenly arrive in a predator-free situation (exceptions noted for isolated islands where medium and larger predators failed to arrive or evolve -- remember the species already there invaded too, if much longer ago).

This is exactly what has happened in my locale.

And cats generally don't survive away from human influence. Other predators think they're very tasty and all too easily caught. Cripes, in the desert I couldn't grow cats fast enough to keep the owl and coyote buffet stocked. Every cat that went outside the fence got eaten.

Where I live, every cat that gets into the wild, breeds more cats. I used to hunt to help the farmers out (mainly with wild rabbits, goats, pigs and foxes) and they would carry a ball pean hammer to deal with the nasty little bastards.

Cats are very successful predators here and there are too many of them killing off the parrots, marsupials.

And considering that in an urban or suburban setting you will have either free-roaming cats, or assloads of rats and mice, which do you choose??

We have several species of owls, kookaburras, kingfishers, hawks, magpies and surprisingly, ducks, that all love to eat mice and rats

Maybe you'd prefer to import weasels, foxes, and skunks. Rabies ahoy!!

We have a lot of foxes, pythons already. Hunting fox is pretty hard and kind of funny

Funny how the same people who decry free-roaming cats usually support "wolf reintroduction" in the western U.S.

I don't. I think it's fucking stupid. Here it's people saying that about saltwater crocodiles and if you've ever seen a 5 metre croc jump out of the water you understand primal fear. So wolf's - no - it's a bad idea as well.

Comment Re:Sweden worries about theirs too... (Score 1) 319

You ask for citations but haven't provided them yourself. You freely admit to not reading the citations when that are provided. You can criticize my numbers but they were provided for people to lazy to do the work themselves. If you don't like the frame of reference I've provided, so that you have to do less thinking, provide the math yourself. You have the references, go dig out the peta joules figures for decommissioning and do the work for yourself.

Where are your numbers for AP1000 lifetime output in peta-joules?

Define 'tested'.

Go look up the NRC's definition.

We can't realistically get rid of the old reactors until we get new reactors built.

Why?

Or maybe I'm more familiar with how complex modern(ish) aircraft are.

And perhaps I am more familiar with the relevant aspects of how complex the Nuclear reactors are. You are the one who wants to talk in car analogies.

Except of course that we now have a bunch of them still operating that are older than that.

Citation please - where are this bunch of functioning 60 year old power reactors?

I think you're full of it.

Considering your last statement, that's quite ironic. If you have a valid argument, then back it up with some facts of your own.

I'm trying hard not to be as rude to you as your are being to me. Read my sig, I'm not talking about my ism's. Your welcome to your opinion however despite your numerous calls for citations, which were provided, you are yet to provide any of your own - or any work of your own whilst admitting you haven't even examine the citations you asked for in the first place.

Comment Re:"Systemd developers have rejected ..." (Score 1) 697

Since the UEFI is not accessible for change:

-The kernel efivars implementation: for modeling these things as plain files with 'rm' meaning delete from firmware (you can rm /dev/* all day long, and not actually affect any of the referenced devices). Should have made removal be a special ioctl, even if otherwise normal files.

IIUC, so that when you remove the character device it doesn't allow and unlink to reach the UEFI? Is that the implementation issue you mean? Surely the kernel can abstract the access to UEFI to allow writes to pass and just remove the character special device on an unlink so the machine still boots the hardware.

I do rm -rf / more often than you would think. Sometimes I deliberately fail systems this way while they are running so I know how they fail when I loose a filesystem with a running application, it helps identify what is happening if I see the same thing occurs on live systems. It doesn't mean I want to trash the test boxes though.

This kind of explains some hardware failures of some hypervisors we had last year. We were scratching our heads at how voltage spike could take out two machines the same way through 10 of thousands worth of power conditioning gear whilst they were powered down, they both had corrupted UEFI bios, everything else was fine.

Comment Re:Not at all (Score 1) 151

I don't think anyone is going to convince you that it's a cat's nature is to hunt and kill, no matter how big or small. Probably because you love cat's and don't want to believe they can do that much damage.

The issue is not whether cat's are or are not responsible, the issue is responsible pet ownership. Cat's are beautiful animals and wonderful companions for people, however they are not toy's and many get dumped. When they are feral, they are quite vicious and, they are as equal an issue as other introduced predatorial species.

It's not the animal's fault, it's people's fault for not controlling them. I have several friends who have cat enclosures that extend inside and outside of the house. That is them accepting the responsibly of owning a cat and the steward ship of other animals that aren't pets. I've got nothing against people owning pets and controlling them in their own home, birds in cages, cat's in houses and dogs in back yards or laundries and on a leash elsewhere.

Outside of the confines of a domestic situation they are to be destroyed, including rabbits, foxes, pythons, cane toads, minor birds and anything else humans have introduced into habitat where they don't belong. Hopefully that might give native species a bit of help surviving and adapting and it's the least we can do considering how often we have fucked up this way.

Saying any pet with predatorial instincts released into the wild won't hunt or kill is like saying they won't get hungry or use their natural instincts to survive.

Comment Re:Sweden worries about theirs too... (Score 1) 319

Ah, problem is that this isn't a valid conversion. Electric energy is 'more valuable' than heat energy, just to start with.

What isn't a valid conversion?

The conversion from petajoules a second to Terra Watt hours was to give those too lazy to make a conversion some context. If you are in possesion of the figures for the lifetime heat output of a AP1000 in petajoules then perhaps we can discuss it in that frame of reference?

Than currently existing reactors. My view is that we're debating the safety differences between a Honda Civic and a Toyota Corolla when everybody currently on the road are driving Model T Fords.

My veiw is we are debating two types of Nuclear Reactors, one (EPR) with systems that have been used and tested and one (AP1000) with a untested design compared to (GenII) established reactors.

Cars aren't highly radioactive at the end of their service life and they don't release radionuclides in an accident, so I think reactors are too complex to be compared to cars.

Even though aircraft still aren't as complex as a nuclear reactor, do you think aviation authorities would allow an untested aircraft design to make regular service routes with passengers?

There's plenty of energetic return.

I think I'll stick with the work of the Universities around the world and the work of the Nuclear Industry itself to base my opinion, that statement has been disproved by their work. I don't think you would be able to provide a citation to back that statement up.

The way things are going, they'll still be around after 100, like the B-52.

Not unless you can change the laws of physics and stop neutrons from bombarding the inside of the reactor vessel. That is what limits the service life of a nuclear reactor to 40-60 years.

Comment Re:What could go wrong (Score 1) 405

" The Intergovernmental Panel of Climate Change considers sulfur hexafluoride to be the most potent greenhouse gas per molecule; one ton of sulfur hexafluoride has a greenhouse effect equivalent to that of 25,000 tons of CO2."

So much for green energy...

You may not realize that considerable amounts of uranium hexafluoride is created and used in the enrichment of uranium for reactor fuel as well.

Comment Re:So what if it fails (Score 1) 405

What you say is anathema in a society ruled by free market capitalism that focuses only on the next quarter.

No it isn't. It acknowledges that to succeed you must first fail. Rarely is a first attempt at anything successful otherwise you wouldn't have a saying such as 'practise makes perfect'. Incremental improvement is how many things have been developed. This is no different.

Comment Re:Sweden worries about theirs too... (Score 1) 319

I'm pretty busy my tardy reply...

Do you happen to have a link for that citation?

To what figure? You have been provided with a citation for these before.

I tried googling it. It's also less than a decade of operation energy for the plant.

I think you mean the decommissioning figure. It comes in at just under a third of the lifetime output of an AP1000.

Still, it seems an odd metric, most everybody else uses money.

Yeah, I've seen that too. They use money to measure industrial energy consumption and convert that to petajoules.

1. Who says TMI's thermal containment ratio is the important part? TMI's dome didn't fail. To my knowledge, the dome has never failed in any nuclear accident.

So it's probably not a good idea to skimp on them. We've seen what happens when cooling fails on them.

2. Are you seriously saying that having the concrete dome act as a heat exchanger isn't something we can simulate?

No, I'm saying that reactor systems that get put into operation are based on operational experience and then built on. That incremental design in reactors is there for a reason and that there is no operational experience with containment domes acting as heat exchanges *and* containment facilities.

That means, the basis design issues have not been exposed and the failure modes are not known.

Consider Fukushima - even with 'strong' domes they ended up with radioactive release because they had to pass water through the system in order to keep them cool enough to prevent problems. If you design the dome to be able to transmit enough heat OUT OF IT, without circulating water, that allows you to keep tighter control of the radioactive materials. Which is the important part.

Since you mentioned Fukushima, it is a good illustration to compare to AP1000. American Society of Mechanical Engineers tested the GenII design and exposed it's two main failure modes by testing a full size reactor core that had not been fueled. They based the mathematical modelling to calculate predicted events based on the behavior of the reactor under certain circumstances, which led to process to operate the reactors for the owners to use.

Keep power to the cooling and to the gate pair seals for the cooling pools. That reactor failed exactly as predicted because there was a build up of reactor operating operation experiences that came from operating reactor systems and understanding them. How many tons of water were above the spent fuel, what pressure the reactor would be at when it started producing hydrogen.

AP1000 is a scaled up AP600 design, with a lot of missing changes that I lost interest in researching. So apart from the heat exchanger issue there is missing systems that should be present to suit the increased capacity, so it should be a larger reactor.

Testing a major new design like AP1000 would require a similar effort as the GenII, only on the dome instead of the reactor core, so you could understand the failure modes. You do that because you don't get a second chance. You need to know what it will do. How do you know what failure modes to expect. No, I don't think it is something we can simulate with enough certainty.

The important part is 'appears'. When I did the math on predicted core events, AP1000 was less likely to have an accident, but a fleet of AP1000 reactors with matching capacity to a fleet of EPRs would have a very slightly higher incident rate.

and that math is based on simulated experience instead of experience. So the predicted core events appear relevant.

Still, in both cases we're looking at around a couple orders of magnitude less likelihood of an incident, which is my point.

less likley of an incident in what?

An AP1000 that gets built is better than and EPR that doesn't, leaving us with an ancient reactor or a replacement coal plant.

I can't see it happening. Nuclear power is too expensive, there is no energetic return. It maybe fantastic and amazing but it is also pointless.

Actually, they'd probably last a century or more at this point. Most of them, at least.

As decaying relics of a selfish era after being operated for 40 or maybe 60 years.

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