Monthly Archives: July 2013

Partitioning with an SSD

I have a new laptop (“ultrabook”) with, as appears to be the norm these days, both a regular hard disc and an SSD device.  The latter should be fast and efficient, but needs to be carefully managed due to the limited number of writes it’ll accept.  Hence anything like a big build with the GNU toolchain has to use the regular hard drive.

I’m thinking through how to partition it.  I presume putting the root of the filesystem on SSD will benefit performance, and the core stuff like /etc, /bin, /sbin and /lib.  And /boot, though I expect rebooting to be a rare thing unless I have trouble with ACPI.  I can tune that to avoid writes with noatime and no journaling.  I expect /var and /home and a swap partition to be kept on the regular hard drive, and /tmp to cohabit with swap, without any need for customisation.

What about /usr?  Development work involves a lot of writes to /usr/local on “make install”.  It’s an order of magnitude less than will be happening on /home, but perhaps I should nevertheless ensure at least /usr/local is on the regular disc?

And what about /dev, /proc, /mnt?  Do any of these filesystem entries map to hard disc activity I need to consider?

I understand hibernate-to-disc is one of the biggest gains of having an SSD.  Can I hibernate to SSD without having a regular swap partition there?  How much does it really gain, and can it be tuned to minimise SSD wear?


I’ve been on the ‘net a lot longer than you.

Well, that won’t apply to all readers.  This blog is aggregated at Planet Apache, so is likely to cross the feeds of some true veterans.  But I’m sure I’ve been online far longer than any of the politicians or journalists who are getting into another frenzy about online porn and ‘protecting’ the children.  Without getting into the nitty-gritty of what counts as an ancestor of the modern ‘net, I first accessed a computer remotely in 1983, subscribed from home and saw my first online pics (of sorts) in 1987, and got my first access over a ‘net using today’s protocols in 1990.

And in all that time, I’ve never encountered anything I’d describe with any certainty as porn.  The most dodgy material I’ve seen is at the sites of trashy newspapers: specifically the Daily Mail (to which I occasionally follow a link) and Pravda (which I use as a test site when developing internationalisation software like mod_xml2enc).  Both of those seem to bombard me with lots of pics of scantily-clad young people, predominantly female.

And violence?  I don’t read novels online, though I might indulge in occasional dodgy media.  Far and away the most violent content I’ve encountered is music from less politically-correct times, setting words from that ultra-violent text, the Bible.  Blessed is he that taketh the children of the heathen, and casts them upon the stone.

So how is this relevant?  I think it firmly gives the lie to the myth that you can stumble inadvertently on anything nastier than you’d see in your local newsagent or bookshop.  If you want porn, you have to seek it out proactively.  And if you seek proactively I expect you’ll find it, regardless of anything idiot politicians do to try and stop you.

The Rape of Lucretia: Illegal online?

We already have the censor blocking a widening range of contents.  Now apparently we’re to have a whole new raft of Big Brother legislation.  So as a very minor protest, I just googled for contents that will become explicitly illegal.  Tizian’s Rape of Lucretia looks pretty unambiguous: it’s not merely a representation of rape (enough to make it illegal), but true, violent rape!

In fact, I think today’s news just prompted me to seek out the nastiest image I’ve seen in 30 years online.  The further they go in the direction of book-burning and aggressive censorship, the more I shall feel inclined to opt out.  I certainly won’t accept filtering of my ‘net contents while I have any choice[1], and if choosing Shakespeare over Bowdler puts me under suspicion from Big Brother then so be it.

I have no interest in porn (and 30 years to prove it), but now legislating to make it ‘impossible’ introduces an element of interest.  How might I go about finding it?  A search for “Rape of Lucrece” finds the soon-to-be illegal image here[2], but what search term might find something more modern?  Maybe I can get a handle on some search terms by looking at the spam appearing on – and more usefully being filtered from – this blog.  Here’s a sample, though those particular search terms are probably long-since outdated.  I’ll leave the details as an exercise for the reader, but if you start a blog at you’ll have access to an akismet log containing lots of clues, likely to be more current than any stupid block-list.

[1]  Unless our governments were to do something genuinely useful and take serious action against spam.
[2] At least, logically speaking.  I expect they’ll find a loophole for anything that can get itself classified as art.

The Sentinels

Living here, I have lots of nice places within easy cycling distance.  Indeed, also walking distance.  But what I’m missing is places to walk.

The trouble is the monster main road: the six-lane dual carriageway along the estuary.  Walk that and not only do I get filthy on the outside, but the lungs fill with crap so I feel grotty throughout.  The third road that actually goes somewhere is no better: it’s small but busy, little different to walk, and much worse to cycle.  Ouch 😦

On a bike, these roads have the redeeming feature of brevity: it’s never long before I can get off them and onto something nicer.  On foot, no such thing: they’re all a barrier to going out.  Fortunately there is an alternative: I can go up the hill a short way on quiet residential streets (enjoying the view) and thence into footpaths and parkland.  I can make a pleasant enough short walk mostly off road: for example up to Efford Cemetery, then back on another variant of the route.  Another direction from the same start takes me to Marsh Mills, which is a hub of terrible roads, but also a vast retail park where I can get many things I’d hitherto have expected only to find online.

What about getting to any kind of walking country?  The Plym Valley, the Coast Path, or even just across the estuary to Saltram?  Access to any of these destinations is cut off not merely by the road, but by the Sentinels: monuments to terrible design that turn a simple crossing into a nightmare.

Let’s take a look at what I have to navigate to get home if I’ve just been across the estuary.  At the head of the estuary it narrows rapidly to a fairly small river, and that is where transport routes converge.  First the A38 parkway – the big road, which is elevated – appears overhead on the right.  The landscape becomes one of urban dereliction, and vegetation gives way to polluted-land scrub.  Next the path rises to go over the railway.  Immediately to the left the railway goes over a bridge across the river, while to the right, the slip road to the parkway is tantalisingly close (as seen in google maps from the slip road).  Either railway bridge or parkway would take me where I want to go, but both are firmly inaccessible.

Instead the path descends again the far side of the railway and goes diagonally under the parkway and its slip roads on both sides.  Returning to the river upstream from rail and road, there’s still no crossing, so I have to walk some distance up the river until I hit another road, the B3416.  This is a five-lane dual carriageway.  If it’s not too busy I can cross the first half painlessly, but for the second half – where the traffic comes sweeping round a blind bend from the parkway – I have to wait (usually quite a long time) for the lights to change.

Now finally the way is clear to turn and head back in the direction I need to go, following the B3416 back to the parkway (crossing another couple of minor roads on the way).  This time I’m at the level of the roundabout, so I have to cross the slip roads in three crossings.  Approaching the roundabout, the slip road is bifurcated, so two separate crossings – the first two lanes, the second three – are required.  Fortunately the lights for these give me plenty of time, as their real purpose is to control traffic entering the roundabout.  Now back under the parkway and some way along it, until I can cross the final slip road – again with traffic sweeping round a bend at me – to my side of the estuary.

Phew!  At least that way there are light-controlled crossings of all the big roads.  The other evil Sentinel – to get between Laira Bridge and Plymstock – has no such help: pedestrians are faced with a choice only of which of the big dual carriageways to cross.  And of how far out of the way to go to put distance between yourself and the roundabout, so you can at least see what traffic is coming on the road you’re trying to cross (though that only works on the bypass: the other way has too many roundabouts to get a relatively-safe distance from any of them).

Yes I do enjoy cycling, and none of these are as bad from a bike – provided you’re not scared to assert yourself and take the lane for wherever you’re going, which may mean crossing lanes of traffic.  But walking is surely the most basic and natural way to get out, and it’s a bit miserable having to do battle with these ghastly Sentinels every time.  Especially when it would be so easy with a little thought to give us some decent routes!

Powering the future

I have a few quid invested in the well-known forms of renewable energy.  The more successful investments are in managed funds which benefit from venture capital tax breaks.

But I’ve hitherto been missing what is surely the UK’s best renewable energy resource: the sea that surrounds us.  In particular the tidal flows that raise and lower vast amounts of water around our coast, completely reliably, every day.

Back in the 1990s when I worked with satellite images, one striking set showed the shallow waters of the North Sea off the Essex and Suffolk coast, where the phase of the tide can be seen from space due to the surface wave patterns caused by the rapid tidal flow in and out.  Mile after mile of shallow water and powerful, reliable flows: westward as the tide rises, eastward as it falls.  Why are we not installing underwater turbines to harness all that energy?  In places there are wind turbines harnessing an altogether more fickle source, so there is presumably even the infrastructure to erect turbines and harvest energy!

Well, I haven’t found anyone building tidal stream technology in the North Sea, but there is a credible alternative suitable for certain coastal locations and capable of generating substantial amounts.  And there is a project to build a tidal lagoon in Swansea Bay.  It looks like a win-win: they’ve gone to a lot of trouble to design a facility that serves not only to generate substantial power, but also to make an environmental and recreational virtue of it.  It appears to have a good level of local support, judging by what I can find in sources such as comments at the local paper’s website.

And the project is open for  investment.  And it’s offering EIS tax breaks, which are even better than the venture capital breaks I enjoy on other investments[1].  And due diligence gives me confidence in the management, not least the man in charge who has a very impressive track record and a lot of his own money at stake.

That’s a lot of very positive boxes ticked.  Today I finally got around to filling in the application form and writing my cheque.  I’m investing in our best future energy source.

[1] 30% tax break up-front, with a lock-in of just 3 years, compared to 5 for Venture Capital.  And further downside protection in that if the investment fails I can offset any losses against tax all over again.

Democracy Campaigners

The phrase “Freedom Fighters” has long been a euphemism.  If you ever hear it used in earnest, it’s a clue that you’re hearing something from the archives of yesteryear.

Democracy Campaigners” is on the same path.  Journalists may still use it, but we know that it means no more than a faction we would like to support against some government we don’t like.  Sometimes it gets used in support of groups that are at least arguably actively anti-democratic.  Can’t be long before it becomes such an obvious euphemism they have to drop it.  Which is a shame, because just occasionally it may still mean what it says.  Burma, for instance, where supporters of Aung San Suu Kyi have legitimate democratic credentials.

And now Egypt, where supporters of deposed president Morsi appear to have similarly valid credentials, and are being slaughtered at a rate that makes the early stages of the Syrian civil war look like a gentle restraining hand.  Except, noone is calling them any such thing: they’re just “supporters of …” (as if their man didn’t have a mandate).  Or worse, just “islamists“, as on the news a few minutes ago.

History is being written, and the writers are apparently intent on relegating Morsi to a footnote.  I guess Egyptians will have to go on voting until they Get It Right.  Or revert to emergency rule, made necessary by all those terrorists who suddenly appeared – and who will be a reason they won’t be better-off even under a hypothetical government that is both benign and competent.

Though to their credit, our media seem to be coming down (albeit hesitantly) in favour of calling a coup a coup.  There’s a word that looks – for now at least – to be surviving the advance of newspeak.