A blog about skating and cycling, or vice versa

Watt Support?#

Tue, 02 Oct 2007 23:53:00 +0000

I wrote

Battery query: I have the 3 cell battery for this machine, which is labelled as 28Wh @ 10.8V - so I calculate the expected capacity as 2.55Ah

However, /proc/acpi/battery says the "design capacity" is 1481 mAh. Actual battery life is ~2h30, but the system indicates 0% at 1h30-2 hours, so I don't know when to save work and hibernate. I have tried (twice) a full charge and discharge to calibrate the battery as described on your web site, but it has had no effect. 

 # fully charged, and with the ac adaptor connected 
dan@toy:~$ sudo cat /proc/acpi/battery/C1B6/* 
alarm: unsupported 
present: yes 
design capacity: 1481 mAh 
last full capacity: 1481 mAh 
battery technology: rechargeable 
design voltage: 10800 mV 
design capacity warning: 75 mAh 
design capacity low: 15 mAh 
capacity granularity 1: 100 mAh 
capacity granularity 2: 100 mAh 
model number: Primary 
serial number: 29392 2007/02/10 
battery type: LIon 
OEM info: Hewlett-Packard 
present: yes 
capacity state: ok 
charging state: charged 
present rate: 528 mA 
remaining capacity: 1467 mAh 
present voltage: 12337 mV

How do I make the capacity gauge work? Linux kernel version is Linux toy 2.6.22-2-686 #1 SMP Fri Aug 31 00:24:01 UTC 2007 i686 GNU/Linux

HP replied
Dear Daniel,

Thank you for contacting Hewlett-Packard's Commercial Solutions Center.

This is with reference to your e-mail regarding the HP Business notebook Nc2400.

From the information provided in your e-mail, we understand that the Battery is not providing the optimum performance

We would like to inform you that we do not support Linux Operating system because of which we would not have any idea regarding the capacity gauge.

We would like to inform you that different Operating systems and its functions would consume different amounts of battery power. For e.g. with Windows XP installed, the battery should provide 2.5 hours of backup. While with the Vista Operating system, it would be 1 - 1.5 hours. This is subject to the number of applications running and devices that are connected to the notebook.

In order to check for the battery you could download and install the battery health test from the following web-link:

http://h20239.www2.hp.com/techcenter/battery/battery_ts.htm?jumpid=reg_R1002_USEN

This would only work for the Windows XP version.

I have a suggestion: if you do not support Linux (and I suppose I shouldn't have been misled by the claim on your web site to be "the global enterprise open source and Linux leader" into believing that you might), then do not provide it as an option on your web form for submitting support requests. Actually, I have another suggestion: learn to read and write English, and then maybe you'll be able to (a) address the issue (design capacity apparently misreported) instead of fobbing off with "we would not have any idea", and (b) understand the correct use of the word "because".

In the meantime, http://www.notebookreview.com/default.asp?newsID=3537 seems to describe a similar problem, albeit on different hardware

Seasonal variation#

Wed, 10 Oct 2007 01:56:23 +0000

A Cologne race summary: good end to a bad season

On the basis that: I had a cold, I hadn't skated seriously since, uh, Goodwood, and I hadn't skated at all in speedskates for about six weeks (except for the LFNS two days ago, when I skinned my knee)[*], my game plan was "don't louse up the start quite as badly as last year, but then let's just go round quietly at the back and stay out of trouble". So I guess I was quite fortunate that the line I was following round came in at ~1.17 and put me within 30s of my PB. Finished a fairly disappointing season on a cheery note.

Short race report: started about four rows back, maybe: most of those ahead were teams. Start itself was one of those "tiptoe over the line" experiences, then up the bridge where I found I didn't have quite the gojuice that I usually look forward to on uphills, then reattached myself hear the back of a big line. Stayed there for the duration. It was surging a lot on corners (slow right down to go round then accelerate out again) so a bit of concertina effect which I added slightly to, but I wasn't feeling aggressive enough to push up into the gaps in front: it was easier to push the skater in front into them. Paid the price for my laziness on the approach to the end when I was boxed in by too many people to sprint up the hill (though see excuses above: wouldn't have been going much faster anyway if I had had the space)

Still, best time (1:17:28) of all my races this year. All, er, four of them. And in the aftermath, I'm actually interested in skating again, which is a first for any time in the past six months or so.

While catching up on Andrew Love's blog, I found this , which is great

[*] "A friend came in from out of town A terrible flood"

Grimm Realities#

Wed, 17 Oct 2007 00:24:41 +0000

I've just watched the Brothers Grimm movie all the way through without realising that Terry Gilliam directed it. Presumably that was the reason I rented it in the first place, but it's been sitting around the flat so long now (I've only just acquired DVD playing capability again) that I'd entirely forgotten.

Peaky Knees#

Wed, 17 Oct 2007 00:30:23 +0000

On Saturday we skated to Cambridge: another in Alex's "let's go to the countryside" series, this time we started at Hertford North railway station (roads south of there are not pleasant skating) and headed roughly northwards, give or take, on some roads that were a true pleasure to skate and a few that were distinctly awful. But, that's skating - one of the few oportunities to say "take the rough with the smooth" and mean it literally. 70km or so, we reckon.

I was lacking a bit of zip at the time, which I attributed to two pints and half a bottle of wine and only four hours sleep the previous night. Now I have knee pain walking down stairs, which is probably Natures's way of telling me I'm not as skate fit as i was before my boots went for repair and maybe should have eased into it a bit more gradually.

My plan back in the spring to upgrade my bike gear shifters to Ergo took another step for the expensive yesterday, when I finally decided that I had enough new bits of bicycle to make it worth getting a frame to hang it all on, then putting the old bits back on the old bike. Tifosi CK4 should be here tomorrow, but goodness only knows where my BB and brake calipers (ordered two weeks ago) have got to. The Royal Mail certainly don't. Still need handlebars, saddle, pedals, and then to stare hard at the old bike and decide what parts are necessary to make it a fixer.

This weekend I'm trying Audax for the first time: 100km of hills in mid-Sussex. Hope my knees are better by then.

Skull and cross-Bone#

Wed, 17 Oct 2007 17:56:00 +0000

I think I like not having Galloway as an MP any more, although I am forced to admit that as the only non-LibDem MP to sign the EDM on the Highway Code changes, he wasn't entirely useless. Sent this off yesterday to Meg Hillier -

My attention was recently drawn to the Bill introduced by your colleague Mr Peter Bone (MP Wellingborough) "to require persons of 17 years and under to wear a safety helmet when riding a bicycle", and reading his speech in Hansard I am concerned at some of the claims he makes.

The only statistic he quotes for helmet effectiveness ("85%") is taken from a small study in 1987[1] in Seattle, which has been widely criticised[2] (some would say "discredited") and in fact has even since been revised by its authors. Without wishing to go into any detail about the specific arguments (there are people on both sides with axes to grind) we would be better to consider instead the much larger "before and after" studies undertaken in countries that have already introduced mandatory helmet laws[3] (whether for children or for all cyclists) and there we find that in all cases the number of cyclists has dropped since the law was introduced, and often by an amount that dwarves any drop in fatalities/injuries - i.e. it's statistically more dangerous to cycle in those places than it was before! Mr Bone's claim to have "researched the issue extensively" seems to ring a little hollow if he has not considered these points. Offering his six-year-old as a counterexample is hardly a serious response.

As an MP in Hackney you doubtless already take a certain pride that this Borough has one of the best reputations for cycling in London (see for example the 3rd October Evening Standard report from Andrew Gilligan[4]) and are aware of the basic premise that the best way to improve cycle safety is to encourage more cyclists on the roads - other road users become more aware that they should look out for cyclists. Furthermore, as we're so often being reminded of the perils of obesity and the sedentary lifestyle it seems foolish - to me, at least - to discourage children who want to enjoy this form of outdoor exercise.

Of course, helmets can protect against some injuries (I recently broke one myself, as it happens, and expect that I would have suffered a nasty lump on the back of the head if I hadn't been wearing it) even if not quite to the extent that Mr Bone claims, but it is important not to get the issue out of proportion, and to me the far greater risk is that we put children off cycling by this well-meaning but misguided attempt to improve their safety. We have to look beyond the hyperbole and the "common sense" to examine the actual facts, and the facts of this issue are not clear-cut enough to justify legislation that may have the opposite effect to that intended.

I would be interested to hear your response.

Daniel

References: (of course, everyone has a point of view, and the truth is probably somewhere in the middle)

[1] Thompson RS, Rivara FP, Thompson DC. A case-control study of the effectiveness of bicycle safety helmets. N Engl J Med 1989; 320: 1361-7.

[2] http://www.cyclehelmets.org/papers/d1131.pdf summarises the criticisms

[3] http://www.cyclehelmets.org/papers/d1096.pdf from the Bicycle Helmet Research Foundation, summarises the effects of mandatory helmet laws in countries that have them

[4] http://www.hackney-cyclists.org.uk/new.htm (3rd October) and scan of the article itself at http://www.hackney-cyclists.org.uk/standard_hackney_city_cycling_feature_2-10-7_screenres.jpg

It's somewhat depressing that going by their respective voting records on ID cards/anti-terrorism/Iraq I'd actually prefer to be represented by Peter than Meg

Am I turning into a Tory, or are they? It gets hard to tell.

Nothing succeeds like Sussex#

Mon, 22 Oct 2007 16:50:22 +0000

Mid-Sussex Hilly 100km was cool. Literally so at first - on the way from the station to the start I had to slow down on the descents as I was at risk of losing feeling in my fingers - but once the sun had been up long enough for the air to warm a little, it was just a lovely autumn day. Started 8:45am (15m late, train companies playing silly buggers, then some backtracking looking for the start point), finished 2:15pm, which makes the average speed around 20k including stops.

Lessons learned for next time

("Next time" may be the 3rd Nov 200k that starts somewhere near Reading, but - 7:30am start, ew)

In theory it makes a nice change to have a day's exercise that doesn't involve toasting my lower back, but in practice it's a straight tradeoff with my sit bones: I'll be giving it a couple of days before I sit on a narrow saddle again. Also my right kneecap - front of knee - was twinging a bit (saddle too low, perhaps?) and my neck is sore, I think because I spent the whole ride on the drops as the bar tops lead to an uncomfortably upright position.

So last night I raised the saddle height about 10mm, and rotated the handlebar angle so the tops are level instead of slanting downwards. Should mean that I have a reasonably comfortable second position on the hoods, but we'll find out.

New bike progress: none to speak of. Frame+forks arrived, but still without BB and still haven't bought bars, stem, or pedals.

How the hosts of MIDP#

Tue, 23 Oct 2007 01:15:35 +0000

The only thing that really spoiled the mid-sussex was getting a text message about 20km from the end from one of my servers to tell me it had fallen and couldn't get up - of course, I was not in a good position to do very much about it until I got to the end.

No more! Text entry via the phone is, needless to say, painful, but with a sensible selection of aliases and macros the MidpSSH client should get me through basic administering-a-good-kicking operations. The phone weighs 100g, fits in a jersey pocket, and goes everywhere with me anyway, so no convenience penalty.

Yes, the screen is cracked, that happened last week. Waiting for the replacement part to be delivered ...

Friday Night Ride to the Coast: Southend#

Sun, 28 Oct 2007 14:41:03 +0000

I'm not going to do a ride report as such, because others have already written better ones than I could given that I wasn't paying a whole lot of attention to where we were going anyway

On the order of 50-55 miles, leaving Hyde Park Corner at midnight and arriving in the early morning. Pace was comfortable, with fairly frequent stops for people to catch up. New bar tape meant my ulnar nerves were not complaining, and I spent a lot more time on the tops than the drops - though riding on the hoods still makes me feel like I'm falling forwards, which is a problem on group rides when I want to cover the brakes. New bars (going on new bike) don't extend as far forwards, which may make a difference to that. Shoulders a bit sore (at the time; the effect didn't persist), which suggests either that the seat wants to be further back or that they're just woefully underpowered.

The good news is that my arse was absolutely fine, suggesting that it just needed toughening up a bit and I don't need to go shopping for a new saddle.

Mostly ORMless#

Mon, 29 Oct 2007 16:15:33 +0000

Some years ago I wrote about Object-Relational Mapping. Slightly more recently I actually read something about relational theory - which has tended to reinforce my opinions rather than anything else, and which led to the development of Septeql

(Ten second demonstration that mapping objects to rows is in principle wrong: a table row with attributes NAME="Cthulhu", CITY="R'lyeh", DEPARTMENT="Human Resources" is not actually the representation of Cthulhu, just an assertion that such a being exists (somewhere). Thus, two identical rows does not correspond to two lots of tentacles, merely two such assertions. Now where's your object identity?)

So, I don't know whether I'm doing this for the appeal to elegance or for the opimisation challenge of removing about a zillion (lit: 27) pointer-chasing database roundtrips induced by the ORM approach but either is justifiable in my mind: for each page, let's do a sodding great join on everything we could possibly want (about 1k of characters after transformation to SQL) and do all subsequent processing in memory.

In Lisp we're choosing to represent a relation (result set) as a list of plists (IATWBPF) and ideally we need some tools to process them without further database access.

(defmacro k& ((&rest attributes) &body forms)
  (let* ((args (gensym "ARGS"))
	 (macrolets (loop for n in attributes 
		       collect `(,n (ref ,args ,(intern (symbol-name n)
						    :keyword))))))
    `(lambda (,args) (symbol-macrolet (,macrolets) ,forms))))
;; thus
 #|
(let ((rows (list (list :a 10 :b 19 :c 21)
		  (list :a 1 :b 3 :c 5))))
  (list
   (find-if (k& (b) (= b 19)) rows) ; select
   (mapcar (k& (a b) (list :a a :b b)) rows) ; project
   (reduce #'+ rows :key (k& (c) c)) ; summarise
   (progn (map nil (k& (b) (setf b 'foo)) rows) rows) ; in-place update
   ))
|#

I'm rewriting the Stargreen shopping cart page to use this, and it seems to be working quite well - at least, most of the problems I'm running up against aren't anything to do with databases but are back-button issues, or UI or whatever. The only DBMS sticking point is still that Lisp doesn't have a good concept to map SQL NULL onto, but if we design to avoid that, this does mostly seem to satisfy the "I can use this without continual recourse to documentation/source code" criterion. which I used to decide that Septeql succeeds where Sexql didn't.

Band on the run#

Thu, 01 Nov 2007 02:31:49 +0000

Very nearly finished putting my new bike together. It still doesn't have

The first and fourth of these are, I think, essential for Saturday. The second, only if it rains. The third, well, for a mostly flat course I reckon that if need be I can stick it in the big ring and leave it there.

telent.not#

Thu, 01 Nov 2007 15:03:28 +0000

ww.telent.net is temporarily down, as we've cancelled service on the machine that used to host it. Backups exist and sooner or later I'll restore them somewhere, but in the meantime you may notice that my old blog is offline, and probably there are some missing images here and there on this one.

I got a letter from the Government the other day#

Thu, 01 Nov 2007 23:48:08 +0000

Or more accurately, a letter from my MP, yesterday - a reply to my [[email two weeks ago => Skull and cross-Bone]]. On actual paper and everyfink.

I'm not going to type the whole thing, but here are some quotes

The first quote is a little odd, but I suspect it's a reference to the work done by Ian Walker As for the rest, all sounds fairly positive and it's good to know the LCC (which I recently joined) is doing its thang.

⟪Sep 2007 Nov 2007⟫