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The fishmonger on Cambridge market had octopus in today; neophile that I am, I bought one; it cost £3.32 and weighed about 400 grams. A quick google got me an Australian guide to octopus preparation; they're not that complicated, so off I go.

Full of large pictures of dead marine molluscs )
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I've just watched a rather impressive programme about Caernafon castle, and am pondering doing something castle-based on a bike over one of the Bank Holidays (late May probably - might well want to go to Spain and avunc for the other one) this year.

It looks as if you can leave Cambridge Friday afternoon and get to Conwy (London, walk across to Euston, Chester, Conwy) late Friday evening; the three castles Conwy .. Beaumarais .. Caernafon seems possible on the Saturday unless they're sufficiently awesome that you can't fit three castles and 60k flattish cycling into a day. Caernafon to Harlech over Beddgelert looks good (if knee-eating) fun on the Sunday morning ... what's the next stop after that? To Machynlleth in the evening, see the Centre for Alternative Technology Monday morning and then afternoon train through to Cambridge, or is there another castle practically available?

Am I missing something critical which would make this either unexpectedly more awesome than it looks, or completely miserable?
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This is James and Marian's son Oliver, born about ten hours before this photo was taken, weighing 2.155kg.

I will be seeing him in Madrid in about nine days.
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This is not the chart of a prudent year (and nor really was last year): in May I bought a large computer, which cost roughly all the savings I made in 2011. The large computer came with an implicit obligation not to buy any more computers until 2014, and indeed I have sold four computers this year.

The holiday was in southern India, mostly on a bicycle, and was generally awesome; photos are here, unpruned pictures here but will take more than a little while to load.
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On a local IRC channel, I pointed out 'I know less of iOS development than a camel does of canoeing'; I'd previously used 'than a walrus does of wind-surfing'.

Alliterative expressions of animal incompetence are clearly fun to produce:

rejs+fivemackthan a badger does of baseball (originally 'basketball' but I think the trochee sounds better)
mdwthan a hamster does of hang-gliding
rjkthan crocodiles do of cross-stitch
senjithan an egret does of epistemology


The important things are assonance and a strong mental image ...

Go ahead! The comments are open!
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Since I have a khaki safari shirt, why not wear it? I assert that a Victorian explorer would remove his waistcoat and bow tie only when fighting a crocodile of unusually prodigious size; after battling a tiger it is permitted for the bow tie to be somewhat askew.
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Recently, thanks to [livejournal.com profile] mobbsy, I have been playing quite a lot of SpaceChem.

I suppose it's most like Peeko Computer on the BBC Micro, except that the machine model is multi-threaded (yay!) and lacks jump instructions (less yay); you're given a set of primitives with slightly awkward behaviour and a task to perform, and you have to write the best program to do the job. It seems that I can usually write programs that work, but they are much bigger and slower than the optimal ones whose existence is suggested at the end of the level; and the game doesn't tend to give you advice on style and efficiency.

See: large, slow acetylene and ammonia factories





I know that a lot of my friends play this; how does one build smaller, faster factories?
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I recently took out £200 in two-pound coins, as part of a plan to make carrying large sums of money around with me sufficiently uncomfortable that I'd stop doing it. In particular, if I've just put three two-pound coins in my pocket to buy lunch at the canteen, I don't need to have a wallet, and so I don't have my credit-card readily accessible.

I spent some of them, and counted the rest. Two weeks later, I did the same again; in early January 2012 I did the same again and managed not to spend any before counting them:
Coin type15 October (93)29 October (87)7 January (100)25 February (99)
Normal Isaac Newton gears80698087
Darwin-and-ape [2009]3200
Thistle-and-portcullis jigsaw [2007]3111
Rocket steam-engine [2004]2011
Paddington station arches [2006]2211
Rugby World Cup [1999]1200
Broken-chain abolition-of-slave-trade [2007]1500
Auld Lang Syne [2009]1021
Brunel's mighty hat [2006]0351
St Pauls [2005]0121
Marconi [2001]0102
Gunpowder plot wheel-of-symbols [2005]0133
DNA [2003]0031
Commonwealth Games (Scotland) [2002]0010
Florence Nightingale hands [2010]0010


I think the little-locomotive £2 coin is about the best piece of currency ever issued.

An iPhone 4S costs three treasure-chests like this
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I have been know to factorise large numbers from time to time. I have a fairly ludicrous computer with 48 processors. Processors 6n .. 6n+5 share a memory bank.

When I do 'mpirun -n 24 [job]', I find that the speed of the job changes substantially, and often for the worse, every couple of hours. I suspect the scheduler is shuffling the jobs around the processors; even when I use a taskset to restrict the 24 jobs to 24 processors, it's shuffling them within the taskset. Since memory is allocated in the bank associated to the processor that the job doing the malloc is running on at that moment, and thereafter never moved, this means I end up with jobs running with all their memory accesses to a different bank; this is slow.

My current best-bet is:

taskset -c 0-2,6-8,12-14,18-20,24-26,30-32,36-38,42-44 mpirun -n 24 msieve ...

Allow the job to start (in particular, to allocate the enormous arrays it needs)

for u in $(for v in $(pidof msieve); do echo $v; done | sort -n); do grep -H "heap" /proc/$u/numa_maps; done

to determine which bank the memory has been allocated on, and then manually write a set of taskset commands to get each job onto a core associated with that memory bank. At least the one time I've tried it, precisely three jobs ended up allocated to each memory bank, though the ordering was 723154106374602651025347.

This seems to work reasonably well, but I feel there must be a less crazy way to do it! Any advice?

PS: it turns out that the right answer is to use options in mpirun:

taskset -c 0-47:6,1-47:6,2-47:6 mpirun -n 24 --bind-to-core --report-bindings numactl -l ~/msieve-mpi/msieve/trunk/msieve -v -nc2 3,8

where the taskset clause restricts the job to running on a subset of processors

the mpirun options bind each job to a single processor

the numactl option forces the job to allocate its memory on the processor it's bound to
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Eleven books this month: I've been making rather more use of the Kindle, and been on more train trips than average.

Greg Egan's Oceanic. Egan has written some of the best SF short pieces that I've read in the last decade, and this volume includes several of them. There's a little more idee-fixe coming in at the edges than in Axiomatic, a few stories which assume that the reader finds the quantum multi-world theory as philosophically alarming as Egan or the characters in the story do, but generally it's pretty excellent. library.

Jean Johnson Theirs Not To Reason Why is a piece of formulaic milsf, but you can feel the writing straining with the difficulty of using precognition as a story element. kindle.

Robert Louis Stevenson Treasure Island, because it was free on the Kindle and I hadn't read it yet. kindle.

Daniel Abrahams The Dragon's Path is very well-executed, but felt like extruded fantasy product where what was being extruded was a compote of early-21st-century fantasy; Abercrombie characters in a Scott Lynch world. kindle.

H Rider Haggard Allan Quatermain which is a classic of the Great Imperial Adventure. kindle.

Charles Darwin Origin of Species. Surprisingly comprehensible and clear; I suppose that was why it made such an impact, but I had thought that Dawkins and Gould existed because Darwin couldn't be read on its own, and I don't think that's the case. kindle.

Stella Gibbons Cold Comfort Farm. This one's a famous, broad lampoon of books I hadn't read; there are some beautiful passages, but the sexism fairy has not been kind with it; pulling women out of the morass of rural existence and turning them into the non-working wives of local gentry doesn't feel as much of an improvement as it might have in 1933. A tale of a 1930s rural household being set into well-meaning well-ending upheaval by taking in a relative. kindle.

CJCherryh Regenesis. First-person writing from the point of view of a princeling, born to power (shaped to power before her conception), trying to figure out how to use infinite power in an unforgiving society on an unforgiving planet, and figure out who murdered her mother into the bargain. Paranoid in a very Cold War and fairly explicitly Soviet mode, though everyone around is an awful lot nicer than any senior Soviet I've read about. library paper.

Hannu Rajaniemi, The Quantum Thief. This one had been pretty widely praised, and I'd carefully avoided reading reviews of it, but, well, it's extruded Stross product wrapped around the Count of Monte Cristo. I didn't find that the writing made the concept of alternating lifespans as human and as golem anything like as terrifying as it should have been. kindle.

Stella Gibbons Nightingale Wood. A tale of two stereotyped 1930s aristocratic households being set into well-meaning well-ending upheaval by taking in a relative; quite a well-written domineering father. Again turned into social history by the passage of time, since everything depends on nearly all the female characters being too posh to work. kindle.

Neal Stephenson's Reamde. It's a romp in Stephenson's inimitable style - effectively a series of braided chase scenes covering eight hundred pages - set in the contemporary world and rather reminiscent of the early thrillers co-written with Stephen Bury. kindle.
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As a present to the world to celebrate its fiftieth anniversary, the NRO has declassified its 25-year-old spy-satellite programmes GAMBIT (KH-7 and KH-8) and HEXAGON (KH-9)

http://www.nro.gov/foia/declass/GAMBHEX.html

These are the ones that took photos on film and then returned them to Earth in containers that look a little like Mercury space-capsules; KH-9 is a survey satellite, and is an enormous beast: three metres diameter, too long to fit in the Space Shuttle cargo bay, and with two 2000mm f/4 lenses taking images onto a hundred kilometres of 16.5cm-wide film.

KH-8 is a smaller satellite containing a bigger camera (110cm-diameter main mirror, so half the size of Hubble, fed by a larger 45-degree mirror with a hole in the middle), with 3.75km of 12.5cm film.

Probably the documents with the greatest potential of having interesting lines to read between are http://www.nro.gov/history/csnr/gambhex/Vol%20IIIA%20GAMBIT.pdf and http://www.nro.gov/history/csnr/gambhex/Vol%20IIIB%20HEXAGON.pdf which are the few-hundred-page official histories of the programmes.

The prices and the exact locations of the places the development was done have been redacted.

It's interesting to note that the early Lunar Survey workup for Apollo was done using cameras from a 1960 spy satellite, 'provided through clandestine channels' - I suspect the Mars Reconnaissance Orbiter currently in orbit around that planet has an awful lot of spy-satellite heritage too, though more openly produced (in that the aerospace contractor Bell provided the MRO optics and also clearly provides a lot of optics to unspecified customers)
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Would any of my readers be interested in a tour of Drax, the four-gigawatt coal-fired power station located mid-way between Leeds and Hull? Tours have to be arranged specially, but the logistics are not substantially worse for a small group than for an individual. I am a shareholder, but I don't think that owning eleven hundred nanodraxes will get me any usefully special treatment.

I'll need to ring and get absolutely basic information like whether it's possible to go at a weekend, but I'd quite like to know before then whether I'd be going alone or contemplating booking a minibus. Would be planning to go sometime-in-October, assuming that plans don't have to be made months in advance.

[Poll #1779585]
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It began, as adventures tend to nowadays, in the financial pages. National Grid offering a peculiarly-constituted bond: what for? What are they building? A mighty HVDC line from north-east Wales to Hunterston: but what's at Hunterston? A nuclear power station … a well-run nuclear power station … a nuclear power station with an open day on Saturday … an open day consistent across the British Energy fleet.

A quick call to the Press Office. Sizewell shut. Hinckley Point hard to get to, and shut. A glimmer of hope: Dungeness B. Discussions of railway routing; confusion over the three Ashfords briskly resolved, the new line from St Pancras to Kent eulogised, tickets procured.

An early rise, a hasty ride, an almond croissant; to Ashford International with a bicycle, twenty miles of Kent to cover and two and a half hours to do it in. Rain, short-lived but drenching. Impermeable not so. Romsey Marshes, their lack of charm. Lydd pie shop. The shingle flats, filled with the glaucous sea-kale.

Coffee and fine biscuits. An adequate pace procuring some time to enjoy them. Disaster: no plant tours available. An exceedingly safe presentation focussing on safety to the exclusion of the engineering magnificence that I was there for. EDF's pernicious habit of using 'terawatt' to mean 'terawatt-hour' on the false grounds that the different orders of magnitude make confusion impossible. The control room. Imprecation from local security that I not post my close-up pictures of the controls on the Internet. Yr correspondent's belief that obliging Her Majesty's enemies to decipher at great lengths the principles of operation of a kind of nuclear power station abandoned as uneconomic thirty years ago more to be considered a coup of the counter-espionage kind; yr correspondent nonetheless compliant. A promise that in 2012 it should be permitted to stand on top of the reactor vessel.

The sea-wall from Lydd-on-sea to Dymchurch, considered as an exceedingly fine impromptu velodrome; the sadness of lifting one's bicycle over an obstacle with one's thumb on the reset-trip-counter button. A frankly excessive hill in Sandgate. Sunset over south Kent from the train. The entirely useless stopping-train from King's Cross, discovered in time to catch a better one. Home via a purveyor of fine soups. Fine soup, and a warm bath. The adventure thus concluded.
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I don't understand how the Open University can justify its fee increase.

From the annual report, at the moment it gets about 40% of its income from fees and the rest from the state. With the fees it was charging in 2009-10, it had a surplus equal to about 15% of its fee income.

I get the impression that the OU is one of David Cameron's pets, and I haven't seen any statements that its state funding is being substantially reduced.

Increasing the fees is likely to reduce the number of students, but presumably they've modelled this and expect to end up with a higher total income; and a lot of the OU's costs are proportional to the number of students, so the surplus would go up enormously.
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I know it's that time of year, and I know work is a bit fraught, but if you could see fit not to show that dream where I'm leaving a deserted exam-hall the size of the Royal Albert Hall down half a mile of steep wooden steps, after sitting an unexpected exam in French Literature, every single night I would be much obliged.

Shorn again

Jul. 2nd, 2011 05:41 pm
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Well, it'll grow, and my ears will be pleasantly cool for most of July.

Iconic

Jul. 1st, 2011 08:37 pm
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I'm not quite sure what it's iconic of, but it's definitely iconic.

From the side of a South Eastern & Chatham locomotive

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