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Rainy day, second of three Nov. 12th, 2009 @ 12:52 pm
[info]mouseworks
( You are about to view content that may not be appropriate for minors. )

Nov. 12th, 2009 @ 04:55 pm
[info]bofhcam
I was in early this morning to do some patching. Not as early as is usually the case (07:00) but pretty early nevertheless. It was all going pretty swimmingly until I discovered that the DB I needed to shut down on account of there being active processes/connections. I ended up having to wait about half an hour before someone who was authorised to do nasty things to the DB came into work before I could run some other stop scripts and get the beast of a machine patched. The rest of everything went pretty smoothly after that. I've now only got thirteen machines which're unpatched (still on RHEL5.3 rather than 5.4 + whatever's come out since then), which isn't too bad really.

Kris continues to work so very hard it's embarrassing just how much harder working than me she is. Anyone she applies to work for would be lucky to have someone as devoted as she is to being good at what she does. I just hope it all comes together/comes out for her at the beginning of next week. Of course no matter where she ends up I'll be looking for a job close by and eventually joining her once I've done the 1001 things necessary to allow me to rent my home out (to hopefully some good friends who'll treat it as I would). The whole process occasionally fills me with fear, based on the amount of change (for which I'm universally known as averse to) which is coming down the pipe for us both but which sometimes transmutes into excitement about the new possibilities which'll be coming my/our way. I just wish there was a method through which I can lock it into the latter rather than randomly flickering into the former.

Standard Thursday evening gathering at my place tonight. I should probably head off soon and make sure the house is presentable. You never know what'll happen if you leave a Kris at unattended at home for the day.

Designing society for posterity Nov. 12th, 2009 @ 11:36 am
[info]charlies_diary

(Continuing from the comments/discussion following an earlier post ...)

Generation starships: they're not fast.

If you can crank yourself up to 1% of light-speed, alpha centauri is more than four and a half centuries away at cruising speed. To put it in perspective, that's the same span of time that separates us from the Conquistadores and the Reformation; it's twice the lifespan of the United States of America.

We humans are really bad at designing institutions that outlast the life expectancy of a single human being. The average democratically elected administration lasts 3-8 years; public corporations last 30 years; the Leninist project lasted 70 years (and went off the rails after a decade). The Catholic Church, the Japanese monarchy, and a few other institutions have lasted more than a millennium, but they're all almost unrecognizably different.

Consumer capitalism along our current model simply won't work as a way of running a long-duration generation ship (the failure modes are lethal and non-recoverable). Communism (or rather, Leninism) has a slightly better prospect, but is still a long way from optimal. Monarchism is just a pretty word for "hereditary dictatorship supported by military caste". What are the alternatives? And what do we need to consider when designing a society that can survive for a 500-1000 year voyage in a bottle without exploding? (I'm assuming, for the sake of argument, that suspended animation or life extension technologies don't change the picture out of all recognition; after all, even if you can expect to be alive in a thousand year's time when you reach Barnard's Star, you're not going to get on the ship in the first place if the living conditions are intolerable.)

Designing a space habitat/generation ship with the implicit parameter that the crew are expected to work 40-60 hours a week is a really bad idea; efficiency is the enemy of redundancy, and multiple redundancy (in life support and propulsion) is absolutely vital to any such project (because it provides resiliency that is essential to have any hope of recovering from a disaster). What if the population crashes? If you've designed your ship to require a 40-hour work week by 1000 maintenance crew and you're down to 250 crew, you're going to die. A 10-hour work week, in contrast, gives them a fighting chance of survival in event of a major die-off.

A sensibly designed long-duration hab would require the crew to do just enough work to maintain the necessary skill set (you don't want them to go rusty), but leave lots of time available for education, recreation, and socialisation. You can't build a stable hab culture on material acquisition because it has to function in a resource-bounded environment (although soft goods/intellectual property is another matter, if you want to provide an escape valve for acquisitive urges, or a "training wheels" environment for the market-mediated culture that you might need to revive after arriving in another solar system).

I've been (inconclusively) batting around some ideas with Karl Schroeder — how do you design a society for the really long term? There are a couple of levels to consider: notably, decision-making and economics. And it doesn't look as if we've got any good solutions to either.

Administration first: Democracy is prone to mutation into some other form (kakistocracy, oligarchy, populist dictatorship). Monarchy has a single point of failure and historically only worked when there was a draconian enforcement regime backed up by Malthusian pressure (whenever the lid came off — e.g. with the opening of a new frontier for emigration — the oppressed tended to vote with their feet: aboard a generation ship, their only option would be to vote with the knife). We were somewhat intrigued by the idea of a society with multiple designed-in local attractors, so that over time it can oscillate between different modes of governance (but returning eventually to previous patterns); but nobody's tried it yet.

Another issue to consider is the need for designed-in escape valves. The social pressure on a generation ship is going to be fierce; but if there's a designed-in expectation that, say, 20-50% of the inhabitants at any given time will be preoccupied by non-functional distractions such as the arts or sports, that might go some way to defusing social stresses. Arts and sports can act as vectors for social competition and status-seeking, while being channeled easily in directions that don't consume excessive physical resources.

One thing I'm pretty certain of is that the protestant work ethic underlying American-style capitalism, with its added dog-eat-dog ethos, would be a recipe for disaster aboard a generation ship — regardless of whether it's run as a democracy or a dictatorship. American (or British) working hours are a bizarre cultural aberration — and a very local one. More to the point, competitive capitalism tends to reward increases in operational efficiency, but efficiency is most easily optimized by paring away at the margins — a long-term lethal threat to life in this situation. The "tragedy of the commons" has got to be engineered out aboard a generation ship, otherwise the residents will wake up one [virtual] morning to discover someone's acquired a monopoly on the oxygen supply. And that's just for starters.

(Finally, don't get me started on libertarianism. Economic libertarianism -- in the contemporary American sense -- aboard a generation ship would be just plain suicidal. It's dog-eat-dog capitalism with the brakes off; I'm of the opinion that libertarian ideology is based on a falacious theory of mind, and would in practice degenerate rapidly into a rather nasty form of industrial feudalism. The end point of which is monarchism, and bloody handed revolution. Not the kind of metastable multiple-attractor society I have in mind at all ...!)

So. You, and a quarter of a million other folks, have embarked on a 1000-year voyage aboard a hollowed-out asteroid. What sort of governance and society do you think would be most comfortable, not to mention likely to survive the trip without civil war, famine, and reigns of terror? (NB: communication with the home world is assumed, as is the ability to implement any innovations they come up with that don't require a work force greater than 10% of your people.)


Hermes Nov. 12th, 2009 @ 01:09 am
[info]gothgeekgirl
Hermes


#77, "War in a Stringbag", Charles Lamb Nov. 12th, 2009 @ 06:35 am
[info]vatine
Previously unread.

This is the WWII memoirs of Charles Lamb, who was a Fleet Air Arm pilot during WWII. He was about to get married when the war started, alive when it ended and had, over-all, one hell of a war (in at least two senses I can think of).

Definitely readable, if that sort of things catches one's fancy. I found it most intriguing.
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Valentin's Appeal Nov. 12th, 2009 @ 03:00 pm
[info]snopes_dot_com
Russian scammer's annual message appeals for money to help a struggling single mother and her daughter.

Great Observatories Explore Galactic Center Nov. 12th, 2009 @ 05:45 am
[info]apod

Where can a telescope take you?  Where can a telescope take you?



Two bike-related things Nov. 12th, 2009 @ 02:05 pm
[info]dagbrown

Today I learned (or rather, was reminded) that rear-view mirrors have this cool spring-loaded mechanism so that when they’re pushed forward, they just go BOING back into their original location with no harm done.

Entirely unrelated (honest!) I need to replace the left rear-view mirror on my bike. It currently looks something like this:

The crack happened when I was trying to pop the mirror off its frame to try and get at the bolt underneath, because it had gotten really really loose. You can see the temporary measure I’ve employed in the meantime in that picture of course.


My tweets from the past day... Nov. 12th, 2009 @ 12:04 am
[info]zonereyrie
These are my tweets for the past day... )
Current Mood: twitterpated

"Worn down by racism," Former South Harrison Mayor steps down from council Nov. 11th, 2009 @ 11:11 pm
[info]yesthattom
http://www.bluejersey.com/diary/13442/worn-down-by-racism-former-south-harrison-mayor-steps-down-from-council

This isn't supposed to be what public service is about:
A man who says he endured slashed tires and death threats just before he became rural South Harrison Township's first black mayor is stepping down.
Charles Tyson announced Monday that he would leave the township council today, in part, because he said he is worn down by racism.
Tyson had already given up his position as mayor of the town of 2,700.
It wasn't enough they got him to step down from running the town, they had to get him off council from making any decisions at all.  

[Copied from [info]bluejersey]

Not a great day Nov. 12th, 2009 @ 02:02 am
[info]annafdd
I don't really feel up to explaining, but I have been strangely distressed all day, and ended up not being able to go to my writing group, and feeling cold, miserable, my hands shaking - all very strange.

Good bye to bad rubbish Nov. 11th, 2009 @ 08:02 pm
[info]yesthattom

Apple Safari 4.0.4 Released, (Wed, Nov 11th) Nov. 11th, 2009 @ 11:04 pm
[info]inetstormcenter
Safari 4.0 ...(more)...

Network Maintenance: Saturday, November 14, 2009 at 04:00-06:00 UTC/GMT Nov. 11th, 2009 @ 02:00 pm
[info]dwell, posting in [info]lj_maintenance
On Saturday the 14th at 4AM UTC/GMT we will be upgrading the operating system of our network load balancers to a newer version, one that will allow us to use both CPUs! Nifty, because multiprocessing is nice.

Since we have 2 load balancers, the plan is to upgrade 1 at a time, and there really should be very little impact to our website. Hopefully you won't notice a thing and I'll get to go back to the hotel and watch some wonderful late night infomercials.

We've got a lot of exciting projects coming up for 2010 and we're hoping that we'll be able to deliver them all to you, that you will find it useful/cool/lovely and then you will use the site even more. Behind-the-scenes work like this will give us the capacity to handle the anticipated traffic, so expect a few more maintenance windows especially in the beginning of next year as we've got some neat ideas to improve performance around here! We had the recent 30-45 minute outage yesterday due to one of our logging databases filling up disk space -- not so great design coupled with my human error in handling the initial problem -- and it looks like we're going to finally have some resources to eliminate stuff like that. I can't wait!

As usual, I will be updating status.livejournal.org before and after, just in case you are not able to reach our main website during the work.

Stefano Bonazzi Nov. 11th, 2009 @ 01:58 pm
[info]jwz

Current Music: 50 Foot Wave -- Hot Pink, Distorted

So… C++? Delphi? Markov Chains? Nov. 11th, 2009 @ 09:28 pm
[info]ptomblin_lj

I have a line on a job that involves porting some code that was originally written in R, then in Delphi, and now the researcher wants it re-written in C++, turned into multi-processor/multi-computer friendly (using MPI?), and turned into a plug-in for R. The program as it is now is pretty primitive – he apparently just puts a bunch of parameters into the actual Delphi code then recompiles and runs, and it outputs into a data file. Obviously the first step would be to have a wrapper program that gets the parameters from a data file, and later a wrapper that gets the parameters from however R passes them to plugins.

It’s been a while since I used C++, and the language has changed a lot since then. Name spaces, STL, Boost, auto_ptr, all this stuff is new to me. It’s going to take some frantic reading to get up to speed. Even worse, I have to read the existing code, which means learning a bit of Delphi/Pascal. And I’m going to have to find a decent IDE for C++ – although the consensus on StackOverflow seems to be to go back to the way I’ve always worked until I started using Eclipse last year: gvim, make, gdb, and a web browser open to the man pages.

Even better, the job would mean working from home. The dogs will be happy about that.

Originally posted at Rants and Revelations

If I could do anything I wanted... Nov. 11th, 2009 @ 03:56 pm
[info]mouseworks
( You are about to view content that may not be appropriate for minors. )

Bless Nov. 11th, 2009 @ 08:47 am
[info]annafdd
Jam likes to perch on the windowsill next to the computer, looking out. Today she let me stroke her, purring and trying to sit on the ledge (which is cold, and too small).

This was unthinkable even just a few days ago.

I moved a chair closer. She was a bit suspicious at first, but is now curled up there.
Current Music: FriComedy: 06 Nov 2009 - BBC Radio 4

John Gebhardt Nov. 11th, 2009 @ 03:00 pm
[info]snopes_dot_com
Photograph shows a U.S. airman comforting an injured Iraqi child.

Saturn After Equinox Nov. 11th, 2009 @ 05:35 am
[info]apod

The other side of Saturn's ring plane is now directly illuminated by the Sun. The other side of Saturn's ring plane is now directly illuminated by the Sun.



My tweets from the past day... Nov. 11th, 2009 @ 12:08 am
[info]zonereyrie
These are my tweets for the past day... )
Current Mood: twitterpated

[info]dnalounge update Nov. 10th, 2009 @ 08:40 pm
[info]jwz

DNA Lounge update, wherein the axe falls.

Current Music: Szeki Kurva -- Stars Are Shining
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Layer 2 Network Protections against Man in the Middle Attacks, (Wed, Nov 11th) Nov. 11th, 2009 @ 03:59 am
[info]inetstormcenter
Last month (Day 9 of Cyber Security Awareness Month) we discussed a Man in the Middle (MITM) attack ...(more)...

Sunny afternoon. Nov. 10th, 2009 @ 11:35 pm
[info]reddragdiva

Sunday I went to the Pembury with [info]nyecamden. He fed me. The new laptop and its remarkable lightness attracted much attention.

This evening I went to a museum computer people meetup that got slightly overwhelmed by Wikipedians. Productive and good, I think! Photos to come, if we ever find the XD-card reader. We refrained from entering the pub quiz, it really isn't fair to let Wikipedians into those.


More cats! Nov. 10th, 2009 @ 10:53 pm
[info]annafdd
Jam keeps getting more and more domesticated, if by minuscule increments each day. She now lets me touch her before I give the two of them their breakfast or dinner, provided she is hungry enough. Not every time, but more and more often, I can reach out a hand and she will arch her back and let me catch her tail and let her slid out.

It looks like the nice hand that strokes her when she is lounging under the table or on the sofa, and that she rewards with such purring, is slowly joining up with the Scary Human.

Yesterday I was in bed, watching cat videos on YouTube (as we mad cat ladies do) and one of them was of a very small, very squeaky nursing kitten. Zip was curled up at my feet as usual, and more or less unfazed - she knows by now that my computer makes cat noises now and then.

But at one point I looked to a side and there was Jam, all alert, huge yellow eyes very alarmed. On the one hand, Scary Human, which she does not approach on her own. On the other, Kitten in Distress! She is ten months old by now, and in the wild, she would have had at least a litter of her own. Something in her just would not tolerate a distressed kitten. So there she was, scared by running to the rescue.

I love this little cat.

Anyway, I stopped the distressing kitten noises and when I next looked up, she was stretched out on the bed, trying nonchalantly to inch closer to Zip. I switched the light off very quietly, crawled very quietly under the blanket, and savoured for a bit my feline family resting contentedly on my bed. Then Jam decided that she wanted to play with Zip and they both ran away.

This morning, another shift at the shelter. Now and then I find myself getting all choked up - when I see two sad cats left at the shelter by humans who moved and would not take the cats with them, or by a small kitten with a missing front leg.

Other times, I feel like I am making a difference the lives of these confused, lonely, scared animals. One cat today was a beautiful young tuxedo boy, whom I first saw backed off against the bottom of the cabin. I could see his mouth opening, but could not tell if he was hissing quietly or mewoing.

On closer inspection, he was meowing: specifically, he was begging for company and strokes, because he had been found injured and, as I saw when he moved, one of his back legs had had to be removed.

Whenever I took my hand away, the almost-silent meow of pain came back, so I spent a good half hour perched in a cat cabin, calming him down.

And then there was the white cat who not only ran up to me, nuzzled my ear and wrapped himself around my neck: but proceeded to climb on my head, grip it with both paws, and start grooming me. Poor thing, that can't have been easy.

And the moment when, washing the floor of one of the cabins, I saw Kate pour six or seven tiny kitten into the adjoining cabin, all fluffy, elastic and bumpy.

I am less shattered than I was last week, but just as torn between tenderness and pity.

It also seems likely that they will let me adopt Jam.
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Cookie Monster Sang About Google 27 Years Ago Nov. 10th, 2009 @ 03:07 pm
[info]yesthattom
http://gizmodo.com/5397485/cookie-monster-sang-about-google-27-years-ago


Microsoft November Black Tuesday Overview, (Tue, Nov 10th) Nov. 10th, 2009 @ 10:11 pm
[info]inetstormcenter
Overview of the November 2009 Microsoft patches and their status.



...(more)...

Still on the road, sort-of Nov. 10th, 2009 @ 05:20 pm
[info]charlies_diary

I'm back home today and tomorrow, but off again on Thursday to Novacon 39 in Nottingham. Oslo was about as cold as Edinburgh, and about as dark; although a good time was had by all, all this rushing around in the dark is leaving me somewhat tired, and even a portable battery-powered daylight lamp for dealing with SAD (which has begun hitting me earlier and harder with each passing year since I turned 40) isn't helping much. (No surprise, if you bear in mind that I live 50 miles or so north of Moscow, some way north of every significant city in North America except Anchorage).

In the meantime, I have little to say except that I'm still thinking about the long haul in extra-planetary travel. Running a biosphere (as the past couple of discussions suggest) looks to be a lot harder than most people imagine — we don't even know where all the critical paths lie, and the longer it has to operate the more complex it gets (with failure modes that mostly appear to be ghastly variations on dying painfully and slowly of exotic trace element and micronutrient deficiency diseases). But there's another question that occurs to me. What are the other problems with building and running a biosphere in space?

Here's one: waste heat dissipation.

Vacuum is, as has been noted in the past, a good insulator. At the same time, it looks likely that any long-term human space habitat is going to need shielding from high-energy cosmic radiation (which is probably going to be physical, rather than electromagnetic, given the multi-GeV energy spectrum of the radiation in question). And for long-duration habitability, biospheres are going to need to be complex, multiply-redundant, and to include pathways to recycling micronutrients and exotica (not just for cycling carbon dioxide and water back into oxygen and glucose).

Approximating a space-based biosphere to a sphere would seem sensible — you can maximize the inhabitable volume per unit of external surface area, and the mass of the radiation shielding goes up in proportion to the external surface, not the interior. But radiation shielding works in both directions: biospheres take short-frequency light and down-convert it into long-wavelength thermal energy (the second law of thermodynamics is in play, here). Don't underestimate the amount of heat we need to dump. Per kilogram, mammalian muscle tissue ("us") puts out more watts of waste heat than an equivalent mass of the sun generates through fusion reactions! The waste heat a biosphere produces ought to be proportional to the mass of metabolizing organisms; and that is going to scale with the volume of the biosphere.

So, while it might make sense to make our spherical biosphere as voluminous as possible (to make best use of the dead mass we're hauling around as shielding), it's going to need radiators to dump the waste heat into space (background temperature: 2.725 degrees Kelvin). Their area is going to go up in proportion to the volume of the biosphere, not its external surface area. And they're not going to be a useful contributory part of the biosphere — they have to be outside the cosmic radiation shielding.

What other gotchas associated with the mechanical supports for an in-space biosphere can we expect to run into? (NB: I'm deliberately ignoring propulsion, political/profit motivation, and crew. If you want to talk about the requirements of running a biosphere, that's the previous topic.)


My long weekend Nov. 10th, 2009 @ 05:40 pm
[info]lnr

Rae and Adam invited us and Fluffy for dinner on Saturday to say thankyou to Mike and Fluffy for being bridesmaids. So we got the train to Cardiff arriving late Saturday afternoon with just time to take the dog for a muddy 45 minutes walk before it got dark. Dinner was lovely, with good company and much playing of estimation whist and then hearts after dinner. On Sunday we got up and out of the house about 10:30 and took the dog for another much longer walk, about 2.5 hours with me on the lead for much of the time. I'm still surprised such a small dog is so strong, and so hard to wear out! We ended up with a nice walk along the cliffs though, and Mike and Monster made it down to the beach, although it was a bit too muddy for the rest of us to attempt. We finished off the weekend with a cheap and very plentiful lunch in the pub, and a lovely pint of Brains Dark, before Adam dropped us at the station.

Having gone all that way it seemed like a good idea to take a couple of days off work and go visit Mike's parents too. So we got a train to Newport, and the bus to Chepstow and a lift home from there to their house, for a lovely curry for dinner and much amusement for me with Gina's Wii Fit Plus: I've already put a copy on my amazon wishlist but Mike now tells me I may need to remove it again :) After dinner Evan dropped us at Phil's house for a pleasant evening of gossip and Rock Band.

On Monday we got up late and headed out after breakfast at nearly 12 for a nice little bike ride. 23.1 miles and 2100ft of climbing (and descending again!) in around three and a half hours rather completely wore me out, especially after all the walking the previous days. So we slumped on the sofa for the rest of the afternoon before trying to take Evan and Gina out for dinner. But despite us saying it could be a late birthday present to them they still insisted on paying for their half!

It was lovely to see them anyway, and we had a nice time, and have spent today travelling home again without having to worry about anything more disruptive to the rail network than a cow on the line at Roydon leading to a 15 minute delay. Tired now!


Project management lessons from the FreeDOS Project Nov. 10th, 2009 @ 05:12 pm
[info]milchi_rss

A lot of people seem to think that open source is a magic solution to project management and that open source projects will automatically attract a large and healthy community of contributors and users who will improve the software. This, of course, is not the case. In fact, creating a successful open source project is a really major and difficult effort. You have to deliver an initial promise that people find interesting, attract other people, then facilitate and lead the community, etc. You just have to look at all the failed projects on SourceForge that never delivered any code to see that "open source" is not a guarantee for success.

Even though project management is a key element of every open source project, there are only few resources about this topic. That's why I always enjoy reading about the experience from open source project leaders. Jim Hall, the founder of the FreeDOS project, recently posted a series of four articles which I find particularly interesting.

Here are links to the articles along with a quick summary:

  • Free and Open Source Software: the first article just describes what free software and open source are all about. It also looks at Raymond's model and compares the cathedral and the bazaar style of development.
  • Open source software in the real world: this article summarizes a number of key lessons learned: every project needs a clear purpose (i.e. you have to solve an actual problem); initial users of the software should be recruited as developers; releases are important; and every project needs an active coordinator or maintainer.
  • Cultivating Open Source Software: you need a web site; making the source code availability in an easy way is important; documentation is often hard to write but is vital; you need a bug tracking system and responding to bug reports is important to attract good feedback.
  • Transitions in an open source software project: finally, when you need to hand over the project, make sure to communicate openly, arrange for your replacement and stick around to ensure a successful hand over.

I really like these articles from Jim Hall since they contain a lot of great insights that apply to other projects, so I suggest you check them out!

(Originally published on FOSSBazaar)


#76, "Conventions of war", Walter Jon Williams Nov. 10th, 2009 @ 04:16 pm
[info]vatine
Re-read.

This is the concluding volume of The Praxis trilogy, focusing on Caroline Sula and Gareth Martinez, with a chapter or three of one viewpoint, followed by a similar amount from the other's viewpoint.

It's kinda hard to describe the book other than the single word "excellent!", so I shall have to let it stand at that. Very much recommended, although you probably want the first two volumes, to make this one make any sense at all.
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The ACPI Embedded Controller Nov. 10th, 2009 @ 09:57 am
[info]mjg59
Of course, the event model I described before is far too simple to be worthy of a place in the ACPI spec. At the most basic level, there's more possible events than there are GPEs to attach them to, so there's a need for some further complexity. This manifests itself in the form of the ACPI embedded controller (EC).

The EC is typically a small microprocessor sitting on your motherboard, often implemented in the same hardware as the keyboard controller. It shares a lot in common with the keyboard controller - on PCs it'll usually appear in system io space, with one register for writing a command or reading a status, and a second register for passing data back and forth[1]. There's 256 registers available, so a typical interaction might be to write the READ command (0x80) to the command register, write the EC register address to the data register and then read back from the data register to get the EC register contents.

The embedded controller will often be responsible for tracking information about the hardware, such as the temperature. Attempting to read the temperature through ACPI will execute an ACPI method - in the case of the temperature being monitored by the embedded controller, this method will attempt to read from an EC register. The EC driver then performs the read and returns the result, which gets converted into decidegrees kelvin and passed back to whatever made the temperature query.

But, as mentioned above, the EC also generates events. These may be in response to a user initiated event like a hotkey press, or may be triggered by some change in hardware state like a thermal trip point being passed. The embedded controller will then raise a GPE.

Unlike normal GPEs, the EC GPE is not handled by looking for a _Lxx or _Exx method. Instead, the ACPI tables provide information about the GPE that the EC is using. This may be in the form of a _GPE definition in the EC object in the main ACPI tables, or alternatively may be provided in an ECDT (Embedded Controller Descriptor Table), an optional table that provides all the EC information. In either case, the OS knows which GPE will be triggered by the EC. It then installs a handler that will be called whenever the EC raises that GPE.

Things get a touch confusing at this point. The first thing this handler does is read the command byte, which functions as a status byte on reads. It then checks whether the SCI_EVT bit is set. This informs the system that the GPE was in response to a hardware event, and so the EC handler writes a query command to the EC command register and then reads back a value between 0 and 255 from the data register. This is then mapped to a _Qxx method, with xx representing the number of the EC event read from the data register. Like the _Lxx and _Exx methods, the _Qxx method is then executed.

The problem with all of this is that the EC isn't that fast. When a byte is written to it, it's necessary to read back the status byte and check whether the IBF bit is set. This is set when the OS writes a byte to the data register, and cleared once the EC has processed it. The straightforward way to deal with this is to poll the status byte until the bit is cleared, and then write the next byte, but polling is slow and wastes CPU time. The EC can instead be set to interrupt mode, where it'll fire a GPE when the IBF bit clears.

The EC has one additional function. The ACPI spec allows for an i2c bus to be implemented through the EC, with EC registers mapping to i2c registers. The observant among you will realise that this means that there's an indexed access protocol being implemented on top of indexed access hardware, which is more layers of indirection than seem sane. For additional humour, this is usually only used to add support for ACPI smart batteries. ACPI batteries are generally abstracted behind a set of ACPI methods that provide information. Smart batteries instead speak i2c directly to the OS[2] for no real benefit. Linux handles these devices fine, and while the chances are you probably don't have one, the chances are also that if you do you haven't noticed.

The final quirk of ACPI events is that there's yet another means of delivering events. The term "fixed feature" is used to describe an ACPI device that isn't described in the ACPI tables. A power button may be implemented as a fixed feature device rather than a normal ("control method") device. This is indicated by a flag in the fixed feature block. Hitting a fixed feature power button will generate an ACPI interrupt, but no GPE. Instead the OS has to read the fixed feature block and note that the power button flag is set there. It then notifies userspace appropriately. Sleep buttons can also be implemented this way, but other devices will be in the normal ACPI tables and will generate either GPEs or EC events.

[1] On my laptop, these are ports 0x62 and 0x66 - compare to the keyboard controller's use of ports 0x60 and 0x64

[2] As directly as indirection via the EC can be...

A little bit more about the cl-user map Nov. 10th, 2009 @ 08:30 am
[info]xach

There has been a great response to my casual mention of the CL-USER map yesterday. Almost 50 new people have been added in the past 24 hours. I think it shows interesting patterns and I hope it can be used for Lispers to find each other for user group meetings, Lisp jobs, etc.

A few people have been confused about how to add themselves to the map. There are a few steps:

I should also mention that I didn't create this map. Mirko Vukovic set it up initially and all the people who added their info to it have made it interesting. I just hope more people see it and get some value from it, so I've added it more prominently to Planet Lisp.

Enjoy!

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Capitalism: A Love Story Nov. 9th, 2009 @ 11:21 pm
[info]tskirvin

Capitalism: A Love Story: * 3/4 (out of 4)

I like Michael Moore movies. I suppose that many would consider this a shameful admission; and if I tried, I'm sure I could justify it by talking about how it's a joy to look at pure propaganda. But truth be told, I like Michael Moore. TV Nation was a great show, back in the day; The Awful Truth was pretty funny too. His early movies were amusing, and his stunts were fairly clever and confrontational in a way that I generally respected. And as time went on, his skills as a propagandist have grown - which as done a fairly effective job of counteracting the problems that his increased notoriety has caused.

As such, I did have some expectations going into Capitalism: A Love Story. And I was disappointed.

Part of the problem with Capitalism was clearly that the topic was very broad. The format of Moore's movies is best-suited for a narrow topic, the smaller the better; but this movie is about an entire economic system, rather than the collapse of a factory town or a more narrow political area like gun control or health care. There's never a chance to examine the various sides of the issue in any kind of serious way; there is never a chance to fill in the caricatures, or even the basic theories. The movie simply lacked focus, and

Worse were the stunts - or, perhaps, a lack of them. Moore's cameras sat in on some home foreclosures, which failed to shine any sympathy on anybody involved while also bringing into question why nobody was willing to intervene. Moore attempted to perform some citizen's arrests at Goldman Sachs and other banks; this simply seemed half-hearted. And everything else hardly seemed connected. There were some smiles at the silliness here and there, but even that was hurt by the oddly out-of-place cursing. All in all, it just seemed... badly put together.

Somewhere in between was the quality of the arguments. Moore didn't really attack capitalism in this movie; he attacked the bailout, and he attacked corruption, but he didn't attack the whole system. If he'd left it at that, that'd be okay - it worked okay in Bowling for Columbine, for instance - but but in this case, he took what little he had and called for even more change than he ever had before. Frankly, he overplayed his hand, and even what value the movie had as propaganda was damaged as a result.

It's a shame; there were some interesting details in there, such as the discussion of Dead Peasant insurance policies and (most prominently) a look back at Flint, MI, where it all began. But while the beginning of this story was the best we're likely to get from Moore, this is likely the worst.

* 3/4

URL: http://wiki.killfile.org/reviews/movies/capitalism-a-love-story/

Upper Case Nov. 10th, 2009 @ 03:00 pm
[info]snopes_dot_com
Has a federal judge ordered Barack Obama to prove his eligibility for the presidency in court on 26 January 2010?

NGC 2623: Galaxy Merger from Hubble Nov. 10th, 2009 @ 06:07 am
[info]apod

Where do stars form when galaxies collide? Where do stars form when galaxies collide?



My tweets from the past day... Nov. 10th, 2009 @ 12:05 am
[info]zonereyrie
These are my tweets for the past day... )
Current Mood: twitterpated

Changes Nov. 9th, 2009 @ 09:40 pm
[info]bluebear
On November 5th, my 35th birthday, I was Raised to the Sublime Degree of Master Mason at Gray Lodge #329 here in Houston. It's the culmination of a year-long journey - from Entered Apprentice, to Fellow Craft, and finally Master Mason. I have my Masonic Brothers (and lots of friends) to thank for the fact that I'm still here - without all of your support I don't think I could have made it through Amy's passing.

On November 6th, I went down to Studio 8 Tattoo on Westheimer for my appointment with Zeo (with LilKaffy along for moral support). A couple of hours later, I walked out with my first tattoo:



It's addicting. I'm already thinking of what to get next. It's also rather nice being able to do what I want to my own body without someone saying "No, don't do that. You don't need to do that. I dont want you doing that."
Current Location: United States, Houston
Current Mood: accomplished

ACPI general purpose events Nov. 9th, 2009 @ 10:06 pm
[info]mjg59
ACPI is a confusing place. It's often thought of as a suspend/resume thing, though if you're unlucky you've learned that it's also involved in boot-time configuration because it's screwed up your interrupts again. But ACPI's also heavily involved in the runtime management of the system, and it's necessary for there to be a mechanism for the hardware to alert the OS of events.

ACPI handles this case by providing a set of general purpose events (GPEs). The implementation of these is fairly straightforward - an ACPI table points at a defined system resource (typically an area of system io space, though in principle it could be something like mmio instead), and when the hardware fires an ACPI interrupt the kernel looks at this region to see which GPEs are flagged. Then things get more interesting.

The majority of GPEs are implemented in the ACPI tables via methods with names like _Lxx or _Exx. The xx is the number of the GPE in hex, while the leading _L or _E indicates whether the GPE is level- or edge-triggered. If an ACPI interrupt is fired and GPE 0x1D is flagged as being the source of the interrupt, the ACPI interpreter will then look for an _L1D or _E1D method. Upon finding one, it'll execute it. What this method does is entirely up to the firmware - on most HP laptops, GPE 0x1D is hooked up to the lid switch[1] and so executing it will send a notification to the OS that the lid switch has changed state. The OS will then evaluate the state of the lid switch (generally by making another ACPI query) and send the event up to userspace.

How does the lid end up triggering GPE 0x1D? Things get pretty hardware specific at this point. Intel motherboard chipsets have a set of general purpose io (GPIO) lines that can, for the most part[2], be used by the system vendor for anything they want. For a lid switch, one of these lines is hooked to the switch and the BIOS configures the GPIO as an input. Pressing the switch will cause the GPIO line to become active. The GPIO lines are mapped to GPEs in a 1:1 manner, though with an offset of 16 - ie, GPIO 0xd will map to GPE 0x1d. If GPIO 0xd becomes active, GPE 0x1d will be flagged and an ACPI interrupt sent. The ACPI code will then do something to quash the interrupts, such as inverting the polarity of the GPIO[3], as well as send the notification to the OS.

Why are the GPIOs offset by 16 relative to the GPEs? The lower 16 GPEs (again, talking about Intel hardware) have pre-defined purposes[4]. These range from things like "Critically low battery" to "PCIe hotplug event" down to "This device triggered a wakeup". And the latter is what I'm most interested in here.

Various pieces of modern hardware can be placed into power saving states when not in use. The problem with this is that the user experience of having to turn on hardware before you can use it is not a good one, so in order to make this the default behaviour we need the hardware to tell us that something happened that requires us to wake the hardware up.

There's something of a chicken and egg problem here, but thankfully most of the relevant modern hardware has out of band mechanisms to tell us about things going on. The PCI spec defines something called Power Management Events (PME), which are driven by an additional current that's supplied to the hardware even when it's otherwise turned off. On plug-in PCI Express cards, firing a PME generates an interrupt on the root bridge and a native driver can interpret that, but for legacy PCI devices and integrated chipset devices the notification has to come via ACPI.

The example I've been working on is USB. It's a good choice for various reasons - firstly, there's already support for detecting when the USB controller is idle. Secondly, modern USB host controllers have support for generating PMEs on device insertion, removal or (and this is important) remote wakeup. In other words, as long as the USB bus is idle we can power down the entire USB controller. If the OS tries to access a USB device, we'll power it back up. If the user unplugs or plugs a device, we'll power it back up. If a previously idle device suddenly responds to some external input, we'll power it back up. And it's all nicely invisible to the user.

How does this work? The controller retains a small amount of power even when nominally pwoered down. This is used to keep the detection circuitry alive. When it receives a wakeup event, it asserts the PME line. The chipset detects this and fires a GPE. The OS runs this GPE and receives a device notification on the ACPI representation of the USB controller, telling us to power it back up. We do so and process whatever woke us - if the bus then goes idle again, we can power down once more.

The astonishing thing is that this all works. The only problem we have is that it relies on the machine vendor to have provided the ACPI methods that are associated with the GPEs. If they haven't, we can't enable this functionality - even though the hardware is capable of generating the GPEs, we have no method to execute to let us know which device has to be woken up. The GPE is never answered, we never acknowledge the PME and the hardware keeps on screaming for attention without getting any. And, more to the point, it never gets powered up and your mouse doesn't work.

There's a pretty gross hack to deal with this. In general, we know what the GPE to device mappings are - they're pretty static across Intel chipsets, and while AMD ones can be programmed differently by the BIOS we can read that information back and set up a mapping ourselves. This trick also comes in handy when some vendors (like, say, Dell) manage to implement one of the GPE events wrongly. Everything looks like it should work, but the method never sends a notification because it's buggy. In that case we can unregister the existing method and implement our own instead.

This code isn't upstream yet, but patches have been posted to the linux-acpi mailing list and with luck it'll be there in the 2.6.33 timeframe. My tests suggest about 0.2W saving per machine, which isn't going to save all that many polar bears but seems worth it anyway.

[1] _L1D = lid. Sigh.

[2] There's a few that are reserved for specific purposes

[3] So where before it had to be high to be active, it now has to be low to be active - this means that it'll now trigger on the switch being opened rather than closed, so you'll get another event when you open the lid again.

[4] You can find a list in the documentation for the appropriate ICH chip - the relevant section is "GPE0_STS" under the LPC interface chapter.


Apple Security Update 2009-006 for Mac OS X v10.6.2, (Mon, Nov 9th) Nov. 9th, 2009 @ 11:07 pm
[info]inetstormcenter
Apple has released updates ranging from general operating systems security updates as well has fixes ...(more)...

Friends! Romans! Countrymen! Nov. 9th, 2009 @ 11:26 pm
[info]annafdd
You don't need to tell me that you are not doing NaNoWriMo. Really. I mean this. It is not compulsory.

You don't need to tell in detail how supremely unconcerned you are you are not doing NaNoWriMo. I don't need to. I wasn't assuming the opposite.

You particularly don't need to belligerently tell me how superior you are to such childish pursuits, how tired you are with the whole thing, how silly the whole notion is.

This is my second year of doing Nanowrimo and I will probably not do the required 50,000 words. I am not shattered about it. Last year I found doing it very productive, very liberating, and in the end a lot of fun. It's a good way to free my creativity, and proved me among other things that when cornered I can indeed produce a plot, characters and acceptable prose.

So if you are not doing NaNoWriMo, it's ok. It really is. It is just as OK to do it.
Current Music: FriComedy: 06 Nov 2009 - BBC Radio 4

Flashforward 5-7 (spoilers) Nov. 9th, 2009 @ 10:29 pm
[info]ewx

Episode 5

Spoilers! )

Characters

Updated )

Looking to the past Nov. 9th, 2009 @ 03:54 pm
[info]mjg59
It’s an oft-voiced suggestion that rather than looking at the bad things that happen in our communities, we should focus on the good things. There’s a number of highly successful geek women already – should we not be concentrating on encouraging more of them, rather than scaring people away with tales of thoughtlessness, discrimination and outright abuse?

Let’s draw an analogy. One day, a $20 charge appears on your credit card. You didn’t make it. You report it to your credit card company, who assure you that they take fraud seriously and then do nothing. A few days later, another $20 charge. Your credit card company tells you that such events are rare, unrepresentative of the general credit card experience and continue to do nothing. A week afterwards, another charge. This time your credit card company describes how they’re planning on implementing a brand new anti-fraud system, but that this is unrelated to any events that may currently be occuring and will give no details as to when it’s going to be rolled out. And proceed to ignore any further reports you make about fraudulant transactions.

Would you stay with this company? Or would you take your business somewhere else?

The problem with the “Let’s look to the future rather than spending too much time getting stuck in the present” argument is that it assures people that things will get better without providing a roadmap for getting there. It does nothing to validate their concerns or make them feel wanted within a community. It assumes either that people will stick with a community that doesn’t respond to their complaints, or that it’s possible to construct a community that’s welcome to an assortment of genders, ethnicities and lifestyles without any of those people being represented in the first place.

Ignoring people’s concerns is an excellent way to drive them away from your community. Doing so because of a potential future that’s probably conditional on you having those people in your community is short sighted and self defeating. Ignoring the present doesn’t benefit the future. It benefits the status quo.

(Originally posted here)

Nov. 9th, 2009 @ 04:55 pm
[info]bofhcam
Well, I have a bathroom, and it's finished too. Well, other than me needing to paint a few coats of white and them some moisture-resistant stuff in a colour we want. It looks pretty brilliant too. I think we need another cabinet to replace the one we took down and a new shower curtain but otherwise thus far there have been no leaks and nothing's fallen off or broken. The new height of the floor in there is noticably higher than the landing carpet so we're going to have to get into the habit of not stubbing/scuffing toes on the threshold but otherwise it's smashing. Much much nicer than it was before and much lighter too. The radiator/towel rail is huge which is what happens when you get a free upgrade. I was right about not noticing the little dings and things it has, so that's good too.

Kris and I had a mixed but ultimately enjoyable weekend. For my part I rowed both mornings although I was freezing one day and under dressed and perfectly warm and over dressed the next. I also rowed both sides, which enhances my chances of getting into a boat as I'm becoming truly used to both sides. Saturday we went to Tesco, Sunday... we failed to do much of anything outside the house after our respective morning exercise. I think this was a good thing even if it didn't get paint bought.

Whilest watching an episode of House I managed to thoroughly confuse and upset Kris with a chain of 'logic' that not even I can explain in retrospect. Happily she was more sensible than I was and after my repeated failures to explain myself to either of our satisfaction promptly forgave me and we got on with the rest of the evening in a much better mood. I really have to work on clarifying my thoughts before speaking them out loud. As my mother once (paraphrasedly) told me "you can only upset your partner with the things you say, not the things you think". I will try harder to take a rule from the DIY school of thought and think twice and speak once. Maybe that way I'll be less confusing to be around.

There's rowing training tonight at the boat house (as usual). Hopefully I'll get back the rowing top (in club colours) someone accidently picked up on Saturday morning from the changing room. The training is four four minute pieces at a very hard rate. I think it's going to be a rather tiring experience.

This should counterbalance the relaxing and smoothly running day I've had here at work patching six more machines up to RHEL5.4 and the nice 6km run I had at lunch in the bright winter sun.

Planet Lisp meta-news Nov. 9th, 2009 @ 10:21 am
[info]xach

In the past few days I've made a number of updates and changes to Planet Lisp. If you normally read the Planet via a feed, you will need to visit the site to see some of them.

  • Added upcoming Lisp meetings in the sidebar; easily find Lisp meetings!
  • Added embedded version of the CL-USER Google map in the sidebar; easily find Lisp users!
  • Changed the appearance somewhat to get rid of big horizontal rectangles and lines
  • Removed a number of feeds that had not updated in more than a year; that included some important past contributors like Juho Snellman (last updated in December of 2007) and Kevin Rosenberg.

As always, if you have a blog that's at least partly about Common Lisp, please send me a link so I can consider it for Planet Lisp.

Tags:

80's Flashback on Jailbroken iPhones, (Mon, Nov 9th) Nov. 9th, 2009 @ 02:44 pm
[info]inetstormcenter
Those of us who spent our formative years in the 80's would know, but for those a bit younger, if yo ...(more)...

First sign of the end times Nov. 9th, 2009 @ 02:39 pm
[info]ptomblin_lj

I knew the Digital Cinema project that I’d been on for 6 years was doomed. But I didn’t know how doomed until the last week or so, when former colleagues on that project have suddenly started responding to the LinkedIn invitations to connect that I sent them a year ago. I’m guessing there is a lot of resume polishing and network building going on there right now. I’d say “Poor bastards”, but I’m in no better shape right now, except I did all that 6 months ago.

Originally posted at Rants and Revelations

Fairness Nov. 9th, 2009 @ 11:37 am
[info]annafdd
You know, you can blame Gordon Brown for a lot of things, and I do. But a) as Mitch Benn pointed out on Twitter, he's "trying to run the country under relentless criticism AND GOING BLIND" b) I saw the supposed misspelling. They weren't misspellings. He doesn't close the top of his "o"s, as tons of other people do, and he went a couple of times over the "e" in Jamie.

He took the time to write a condolences letter in longhand. Lots of other people would type it up, print it and sign it. Lots of other people would have a secretary compose it, type it, print it and stamp your signature on it.

There's lots of things wrong with our political class, starting from the attention they pay to the fucking Sun newspaper, but this is ridiculous.

The Fall of the Wall, twenty years on Nov. 9th, 2009 @ 04:52 am
[info]nwhyte
When it ended, 1989 )

Being there, 1986 )

Going back, 1992 and since )

Other walls, and Robert Frost )

The Tipping Point Nov. 9th, 2009 @ 03:00 pm
[info]snopes_dot_com
Did Oprah Winfrey tell her audience that restaurant patrons need not tip their servers more than 10 percent?

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