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I’ve previously written some suggestions for people choosing a portable computer [1]. Basically it’s about how to start by choosing the correct type of portable computer – if you don’t know whether you want a NetBook or a Laptop then you are really lost.
Now there are a range of NetBook type devices which vary greatly in size, weight, price, screen resolution, and keyboard quality.
Probably the first thing to consider is whether a NetBook will be your only portable PC, or even your only PC. I have an EeePC 701 and a Thinkpad T41p (old, but still more than adequate for my needs). When I’m at home I have a server that I use for compiling and other heavy tasks. So while my Thinkpad is old and I wouldn’t consider using it for all my work, as I have a server to use I find that I don’t need anything better. My EeePC is small and under-powered for even medium size compiles, but for most other tasks works quite well. The low screen resolution is annoying as is the tiny keyboard (which prevents me from touch-typing). But my plan is to spend much more time carrying my EeePC in case of emergencies than I will ever spend using it – so saving size and weight is more important than having a more capable computer.
If I had no laptop then I would have chosen a more powerful NetBook (such as an EeePC 900 or 901 – I bought my EeePC when it was outdated). If I had no server then I would have bought a more powerful laptop a while ago (at least something that can run Xen and KVM).
Now in terms of specific features, the first thing to consider when choosing a laptop or NetBook is whether you can touch-type. If you can then having a keyboard that permits it is a major feature. Which then drives the decision of whether your NetBook use will be intensive enough that touch-typing is required (my use of my EeePC does not require touch-typing – I’m annoyed every time I type on it but I deal with it). Of course I do have the option of using a USB keyboard.
When considering reviews of NetBook keyboards one issue that seems relevant is the size of your hands. If the reviewer has fingers that are significantly thinner or fatter than yours then the review of the keyboard may not be relevant to you. I suggest always testing a keyboard before making a purchase decision on a portable computer.
The screen resolution on NetBooks is a significant issue. For most tasks my EeePC 701 is adequate (not great) but there are some programs that require higher resolution, among other things this rules out playing most games (of course the slow CPU also rules out many games). Note that if you hold down the ALT key you can click on the middle of a window and drag it around, so you can work with windows that are larger than your screen (this is essential for programs that have large dialog boxes).
The low resolution of the screen on my EeePC means that there is little space for a task-bar or for windows to be tiled. So while I can comfortably work with 10 windows on one desktop on my 1400*1050 resolution Thinkpad I struggle with 5 windows on the 800*480 display of my EeePC. Some coding and sysadmin tasks can best be done with multiple Xterms open at once, my performance on those tasks is significantly decreased when using my EeePC. So while either machine can be used effectively for a single SSH session, if I need to have 8 sessions open at once then I will have to use my Thinkpad. If I was going to be routinely doing such tasks while on the move then I would have bought a NetBook with a greater display resolution.
The next issue is storage. The machines that are most commonly identified with the NetBook image use flash storage. This makes them resistant to being dropped but also dramatically reduces the storage space (or increases the price). If you have a bigger machine at home then a NetBook with flash storage works well. The 4G of internal storage in my EeePC plus the 8G SD card I always have installed works quite well for me. But I also carry a few USB flash storage devices for extra capacity. Anyone who is to use a NetBook as their primary PC would need to buy a model with a hard disk, and even for some more casual uses the storage capacity of the flash based models may not be adequate.
It seems to me that anyone who requests advice on buying a NetBook without specifying some detail about these issues will end up receiving recommendations for devices that fit the usage scenarios of other people. A machine that perfectly meets the needs of one of your friends may be totally inappropriate for your use.
My final suggestion is to consider the outdated models as well as the current ones. For certain usage scenarios the original EeePC is still a better machine than most of the newer and more expensive NetBooks that are on the market now. My use case of carrying an EeePC everywhere just in case a server happens to crash (or I need to check my mail) is one where the EeePC 701 is slightly better suited than most newer machines – saving a small amount of weight and space is important enough for me to accept the significant feature loss as a reasonable trade-off. As an aside I’m disappointed in the apparent lack of small NetBooks on sale at the moment, it seems that every manufacturer is now making NetBooks which are significantly bigger than the original EeePC and only slightly smaller than Laptops.
ForeignPolicy.com has an interesting article about Cyxymu the first digital refugee [1]. DDOS attacks against LiveJournal and Twitter have been forcing him to use other services to spread his message.
Botnets (large groups of computers running “trojan horse” software that are under the control of a single hostile party) [2] have been around for a while. At the moment a large portion of the spam that is sent comes from botnets. So everyone would benefit in a small way if they were greatly reduced in scope.
But until recently botnets have been mostly an annoyance, sure they were well known to be able to put small companies offline and estimates of the potential capacity of the larger botnets to slow the net access for entire countries (such as Australia) have been circulating for a while. But they haven’t seemed to be really harmful.
When a DDOS [3] can be used to force major Internet services such as LiveJournal to cancel the accounts of members as a measure of self-protection then it really changes the industry. Firstly it decreases the value of LiveJournal, an advantage of the big blog servers is that they can be used to get a message out even when other services are being attacked, LiveJournal apparently isn’t big enough to perform that task. So this effectively puts Google in a market leading position (it seems inconceivable that anyone could DDOS Google). I don’t think that this is a good thing for ISPs, so they seem to have a vested interest in correcting this problem.
Censorship of political comments seems to be against the best interests of any democratic government. So there seems to be a strong case for government action.
The Australian government is currently wasting huge amounts of tax-payer money on trying to filter net access with varying claims of preventing children from accidentally seeing porn mixed in with claims about preventing the distribution of child porn. Of course if they want to stop the distribution of child porn then they want to stop the trojans (for example in the UK Julian Green was found not-guilty of child-porn charges due to the evidence suggesting that a trojan was responsible for the downloads in question [4] and in the US a 16yo boy was charged with distributing child-porn because of a trojan [5] – there are many other examples of this).
I believe that legislation to deal with these problems is long overdue. I think that fines need to be levied against either users who have infected PCs on the net or the ISPs that serve them. It’s not difficult to discover machines that are in a botnet, it will cost some money but the cost will be less than the penalty that is levied for a minor infraction of the road laws so it should be good for the government general revenue.
In the short-term this might be considered to be bad for ISPs (some current customers will drop off the Internet). But in the long term I think that it will be good for their business. In the long term improving the quality of the Internet experience can only result in more people using the net and the people who currently use it spending more time (and therefore money) doing so.
I recently discovered the Help A Reporter Out [1] service.
Subscribers receive three messages every business day each of which contains about 40 queries from journalists. People who subscribe can contact the journalist to provide information or offer an interview. Any journalist can send in a query. Peter Shankman runs this, it seems that it helps promote his other business ventures and there is also a paid advert at the top of every message.
This has to be one of the best services that I have ever unsubscribed from! The vast majority of the questions are about topics that are not relevant to me – there are typically about 6 IT related questions per day out of 100+.
I would like to see a “Help An IT Reporter Out” service. It could consist of a single email per day which might have 10 questions due to a more focussed market. This would take less time to skim read which would make it more appealing to most people who are doing interesting things with computers. Then of course it could allow targeted messages related to different IT sectors (servers, desktops, PDA/phones), technologies, etc. Exporting the questions to Twitter would be good for people who like that sort of thing.
If anyone wants to start such a service then let me know and I’ll promote it on my blog.
A few weeks ago I had a guy from “enviro saver” visit my home to replace incandescent globes with CFLs. Â The original plan was to deliver a water-saver shower head as well but he told me that because I have solar hot water there are no renewable energy certificates in installing a shower head so I couldn’t get one.
The brochure they gave me at my local shopping center when I signed up for this claimed that they are “acting on a genuine concern about the
environmental impact of our Australian lifestyle”. Â But it seems that renewable energy certificates and up-selling of Photo-Voltaic systems is the real aim. I’ve been planning to get a PV system installed so I’ll be interested to see what they offer me.
The CFLs that they gave me appeared to be very cheap ones. Â They take about 500ms to start while the better ones appear to take less than 100ms. It seems to be a reasonable business model to give people a few dollar’s worth of cheap CFL lights in exchange for a good sales opportunity and some renewable energy certificates.
This sort of thing has become popular enough that some thieves are copying the plan. According to the reports people will knock on your door offering free CFL lights, case your home while installing them (got to check every room for old incandescent lights), and then rob it the next week if it looks like there are good things in there.
The companies that offer a legitimate service of replacing lights apparently don’t send people knocking on doors. They have the customers sign up for the service in advance.
But the solution to such problems seems obvious. Firstly get the name of everyone who wants to enter your home. If you signed up for a service then make sure you know who you called. If someone appears on your doorstep then demand photo ID. Camera phones are good things, if someone refuses to adequately identify themself then take their picture, note the number of their car, and give the details to the police.
Keep a log of everything that seems relevant to home security, thieves may attack your home weeks after casing it, so you can’t rely on your memory. Also keep a log in a place where it’s not likely to be stolen, storing it on a computer that is in your home would be a bad idea.
TED.com is a site that is known for very high quality content. Unfortunately on occasion they do get things wrong.
Rob Hopkins in his talk at TED Global 2009 claimed that 1 liter of oil “contains the energy equivalent of five weeks of human labor by 35 strong people” [1]. Now Rob has made a lot of good points and I look forward to watching his lecture when it becomes available, but I can’t let his claim about the energy of oil pass.
First we have to consider the functional usability of the energy. A Prius takes about 5 liters of petrol to drive 100Km and I believe that Toyota is going to improve this in the near future. Let’s assume for the sake of discussion that a hypothetical turbo-Diesel Prius based on the yet to be released new Toyota hybrid drive-train would take 3L of Diesel fuel per 100Km (Diesel engines are more efficient and Toyota is continuing to improve their technology). The Prius weighs about 1300Kg so let’s assume for the sake of discussion that 1L of Diesel fuel can move 1500Kg (vehicle plus driver and cargo) a distance of 33Km.
So the question becomes, how long would it take 35 strong people to move 1500Kg a distance of 33Km? 1500/35 gives a mass of 42Kg per person – any strong person can lift 42Kg with ease (it’s less than the mass of a good Trinitron monitor). 5 * 40 hour working weeks gives 200 hours of work, 33Km in 200 hours means an average of 165 meters per hour. I think that I could carry a 42Kg mass more than 165 meters per hour without excessive effort. If I was allowed to use some form of trolley then I could take it a lot further – I have moved monitors much faster than that while balanced on a wheeled chair!
It seems that the Bicycle Rickshaw [2] is one of the most efficient ways of moving passengers and cargo on roads. According to the reports I’ve heard a 100Kg passenger who comes from a first-world country (and can therefore pay well) will be welcomed as a rickshaw passenger. I think it’s reasonable to assume that a rickshaw driver can transport a passenger more than 33Km in one day. So if you had 35 strong rickshaw drivers working for a day they should be able to transport 3,500Kg of passengers and cargo for a distance that is greater than 33Km as opposed to a hypothetical future-technology Prius which can transport 1500Kg for 33Km while using a liter of Diesel fuel!
Now if we consider the fact that the 1500Kg that the Prius moves is comprised of 1300Kg of car and 200Kg of passengers and cargo we have 1 liter of oil in the Prius moving 200Kg a distance of 33Km vs 35 strong people working for a day and moving 3500Kg the same distance.
According to the Human Powered Transport Wikipedia page [3] someone who is “in shape” can produce 200W of cycling energy for more than an hour – that is 720KJ/hour. I wonder how many hours they could do that for in a day. It seems reasonable that a full 8 hour day of work would comprise at least the equivalent of 4 hours work, so that would be 2.88MJ per day or 72MJ for five 40 hour weeks. Therefore for 35 people it would be 2.52GJ of cycling energy over five 40 hour working weeks!
According to the Wikipedia page on Fuel Efficiency [4] one liter of Diesel fuel contains 38.6MJ of energy. If the energy in one liter of Diesel fuel was converted to motion with 100% efficiency then it might be equivalent to one strong person cycling for 13.4 days.
According to the Wikipedia page on Thermal Efficiency [5] the most thermally efficient engine is the Wärtsilä-Sulzer_RTA96-C [6] which can run at 51.7% efficiency which gives 163g of fuel used per KWh. So the RTA96-C could produce just over 22MJ of usable energy for 1 liter of fuel. That’s about equal to one person cycling for 7.6 days. Also note that the RTA96-C is an engine for a very large cargo ship, smaller engines are much less efficient.
There is no doubt that petro-chemicals are a concentrated source of fuel. I can carry a jerry-can which contains usable energy equivalent to more than 6 months of work by a laborer (according to my rough calculations). But there is no way I could carry enough food to keep someone alive and working for 6 months.
I look forward to watching Rob’s talk when it is available for download, I don’t think that getting one point spectacularly wrong reduces the value of his work. The Transition Towns [7] concept has many benefits to offer, even beyond Rob’s initial plans.
The first couple of times I tried to setup Bittorrent I had a lot of trouble. Here is a basic summary of what you need to do:
btmakemetafile.bittorrent test.iso http://server.example.com:8000/announce
The above command will create a metafile named test.iso.torrent. Note that the server name (in this example server.example.com can be an IP address and any TCP port can be used (it’s generally best to use a port above 1024 to run as non-root). The “/announce” at the end of the string is vitally important, it won’t work without it – and you won’t get any usable error message! I have filed Debian bug report #511181 about this [1].
bttrack.bittorrent --port 8000 --dfile dfile
The above command starts a tracker listening on port 8000 and uses the file named dfile to store the recent downloader information. By default it will only allow downloads for .torrent files in the current directory, the --allowed_dir option allows you to specify another directory and the --parse_allowed_interval option allows you to specify the length of time in minutes between checking for changes to the list of torrent files.
In Debian you can edit the file /etc/default/bittorrent if you want the tracker to start on boot. There is no configuration for starting a btdownload program on boot (for seeding the data). In most cases it’s probably best to just run a couple of seed btdownload processes via screen on different servers and rely on the fact that you can login to restart them if the servers are rebooted.
btdownloadcurses.bittorrent test.iso.torrent
The above command needs to be run on a machine that has the complete test.iso file in the current directory to seed the torrent. Probably most people will use the same machine for creating the metafile, running the tracker, and running the seed download program. But these can all be done from different machines. This is the curses version which works from screen, there is also a btdownloadheadless.bittorrent program that is designed to be run from scripts.
Once all that is done any machine on the net can start downloading via the above command.
For the seed server the most useful option seems to be --max_upload_rate to specify the maximum transmission rate (otherwise it will eat all your transmission bandwidth).
Peter Singer wrote an interesting article for the New York Times which makes a good case for rationing health care on the basis of a ratio of the amount of money spent to the health benefits provided [1]. It’s obvious that given a finite amount of money to spend on health-care and a limited portion of the working population who can be employed in providing it there will be limits to the care that each individual can receive. Therefore it seems inevitable that some people will miss out on care that they need – sometimes to the extent of significantly decreasing the length or quality of someone’s life – at least until we can manufacture fully autonomous medical robots or other futuristic technology to greatly reduce the amount of person-time involved in providing medical care.
The majority of the article concerns the need for rationing health care. Really this is obvious, and it’s also obvious that it takes place right now all around the world. The article is mainly focussed on the US where private health insurance for everyone is being considered and people are afraid of government rationing of health care. But right now they have health care being rationed not for the purpose of saving other people but for the benefit of share-holders and executive bonuses! I wouldn’t really be thrilled if a government agency told me that instead of paying the necessary money to save my life they would rather pay the same amount of money to save two other people, but if a private company wanted to deny me treatment in order to pay the down-payment on another executive Mercedes I would totally flip out! Dr Gabriella Coleman (who is famous for her Anthropology research on “free and open source software hacking”) has written Housebreaking Your Health Insurance [2] to offer some tips for dealing with private health insurance companies in the US with the first tip being “Ideally you should tape record all conversations” – I think that single point adequately demonstrates the problem with health insurance (but there is a lot more).
In the common culture of the US, Australia, and Western Europe it is generally regarded that children are inherently more valuable than adults to such a degree that a choice between saving the life of a child or an elderly person really requires no consideration. So Peter advocates having a measure of the expected years of life remaining before determining an amount of money to be spent – this is logical, reasonable, and fits with the common moral standards in our society.
Peter then goes a bit off track when talking about putting seat belts in buses. One significant thing to consider is that there is a world of difference between preventing an injury and curing it. If you cure an injury then there will be some pain and suffering during the process and the result probably won’t be a full recovery. Being able to walk away from a crash because of a seatbelt is a really good thing (been there, done that).
But things really go awry when he starts talking about medical treatment for the disabled. Firstly he mentions quadriplegia as an extreme case, but to differentiate on the basis of disability you would have to categorise the various disabilities in order of severity. Then of course there are awkward issues such as comparing a quadriplegic who is employed in the computer industry (such as a former colleague of mine) and someone who is apparently fully capable but sleeps on a park bench.
He expressed the idea that someone who would give up a year of their life to cure a disability assigns a lower value to their life. By using that logic anyone who undertakes cosmetic surgery (which has a non-zero probability of a fatal outcome and therefore statistically decreases the life expectancy of the patients) would also assign a lower value to their life, as would anyone who enjoys hobbies such as bungee-jumping and parachuting. But if someone would not be prepared to have their life shortened in exchange for curing a disability that doesn’t mean that there is no value in trying to cure the disability.
I think that the greatest problem in this area is that of making excessive attempts to reach some absolute standard of fairness. No matter what you do someone will end up not having the budget for their health care and they WILL consider it to be unfair. If the amount of money to be spent was strictly based on age then it would be a simpler system to operate which if nothing else would save on administrative expenses and therefore allow more money to be used on providing health care.
I believe that the health care problem is the biggest economic problem that first-world countries face (little things like a mortgage crisis are temporary while health care that is provided now will affect tax revenues in 40 years time). Even if you regard people as being merely assets which are owned by the government then you would have to consider such valuable assets to be worth protecting – particularly children as you never know which ones are valuable until about the age of 21!
I find that in such discussions it’s not uncommon for the more right-wing Americans to advocate allowing people to die if they haven’t taken out appropriate insurance – it’s supposedly their fault. There are two major problems with this, one is that children who are unfortunate enough to have parents who are too poor or unwise to get appropriate insurance will lose. Another is that most people have no ability to understand probability (everyone who has purchased a lottery ticket has demonstrated their inability to make good decisions on such matters). It seems to me that some minimal level of health insurance for everyone along with comprehensive health insurance for children aimed at preventing problems should be provided by the government from tax revenue, the moral and economical justifications for this are both independently compelling.
For the more selfish readers, even if you don’t care about other people becoming sick or dying and you don’t believe that economic benefits will help you there is still the issue of disease transmission. Every time you are in a city area and find yourself downwind of a beggar you have to hope that either they don’t sneeze or that decent health-care is available to everyone. Extremely drug resistant Tuberculosis sounds nasty…
ZDNet has an interesting article about Amazon unselling books to Kindle owners [1]. Apparently the books Animal Farm and 1984 were added to the Kindle list by unauthorised people (Engaget has the original story [2]). So Amazon decided to just remove the books from the Kindles and refund the purchase price.
Amazon has stated a plan to not unsell books in such situations in future – although they will apparently reserve the right to do so if they wish.
It seems to me that Amazon management are amazingly stupid. One thing we need to consider is that Amazon employs a large number of people, some of whom will be criminals and some will act in irrational ways for various reasons. Of the Amazon employees who won’t consistently act in an honest and reliable way on behalf of their employer some will have access to the database which controls the content that is permitted on Kindles. The Journalspace fiasco should be sufficient proof of this problem [3].
If a rogue employee wiped the database of sales in progress it would really hurt the Amazon business model, but if a rogue employee also unsold the existing works (stole property from customers) then it would be much worse.
The “features” of the Kindle would be useful to anyone who wants to make some money shorting Amazon stock. This should be of concern to the directors of Amazon.
Fandom is something that has never made sense to me. If a sport such as football interested me then I would play it. Being good at something is not a requirement for participation, in fact my observation is that amateurs who kick a ball around for fun (without even keeping score) appear to enjoy it more than professional players. Also there are a huge number of support roles, anyone who really wants to support a professional sports team can apply for work – a sports team is a medium size corporation and they have all manner of jobs available.
I have had a few people try to convince me that I am somehow missing out on an important experience by not attending sporting events. But the fact is that there is more than enough fandom in and around the computer industry, so if I was interested in fandom then I could get it without going anywhere near a stadium.
One of the advantages of the free software community is the minimal amount of fandom. There are many opposing opinions which get some degree of fan attention (EG GPL vs BSD license, Linux vs FreeBSD vs OpenBSD, and GNOME vs KDE). But this is smaller than it might be due to the fact that free software development and support are activities that tend to drag in everyone who has interest and skill. When you have been involved in software development or support it becomes difficult to sustain the level of prejudice that is required to be a real fan.
This is not to say that there is a lack of strong advocacy. When a project has received contributions from hundreds of people and support from thousands of others there will be a huge number of people who feel that they have some degree of ownership of the project and therefore react strongly when it is criticised. But I think that there is a vast difference between someone who defends a project that they have worked on and someone who merely barracks for a team that doesn’t include them.
I am continually disappointed by Microsoft fans. Anyone who really wants to support Microsoft knows where they can send their CV. I can’t understand why someone would want to barrack for a team that rejects them – such as people who are unable to get employed by MS but who are still fans.
In the free software community every person who contributes is a member of the team. That includes all contributions, a large portion of which do not include patches to source code.
Currently there is an ongoing debate about a joke that was made during a lecture about free software. I have previously written about why I think it’s inappropriate with regard to children in the audience [1]. For those who are interested in following this mess Matthew Garrett has written an interesting follow-up post with some useful links and a lively comment section [2].
I think that to some extent this is a symptom of a larger problem. That of speakers who take their audience for granted and don’t show them adequate respect. This is an easy trap to fall into, after giving many lectures which are well received it’s easy to become too egotistical and think of an audience as your right – rather than as a privilege that is earned by doing good technical work and explaining it in a clear and respectful manner.
Making jokes for a multi-national audience is difficult at the best of times, often jokes that work well in one culture will fall flat with an audience from a different cultural background. If you give a lecture that contains jokes then some of them won’t work, usually they merely fail by not getting any laughs but sometimes they cause offense. If you tell a joke in a lecture and no-one laughs then it’s probably a good idea to not follow up with any further jokes on that topic, if your speaking skills are not sufficient to allow you to make such a change to your talk in response to audience reaction then it’s best not to plan for a series of jokes. Regardless of the topic of the jokes it’s not a good situation if the majority of the audience is not amused.
Art is also subjectively interpreted in ways that vary according to the local culture and the definition of porn is even more subjective. In my post about appropriate talks about porn [3] the only situation I could imagine where showing a picture related to porn during a lecture about computer science was in regard to Lena and the history of computer graphics (the famous picture of Lena is cropped so that it is not pornographic), and that post did not receive a comment with any other suggestion. We could have a debate about where exactly the line should be drawn. But there are some situations where a line has been clearly crossed, such as a presentation about flash development which included a frontal view of a woman wearing semi-transparent underpants [4].
If you are going to give a lecture about art then there are valid reasons for showing pictures which may be considered to be porn by some people (I can’t imagine a lecture about Greek or Roman statues not having some serious nudity). But if the topic of your lecture is computer science then anything which significantly distracts the audience from that is a failure – even if it’s not offensive.
Presenting material that you find entertaining but which doesn’t interest the audience is self-indulgent. A small amount of self-indulgence will be accepted by the audience, but it needs to be short and forgettable.
If you respect the audience you have to respect feedback. For example if your wife or girlfriend thinks that your talk is great but women in the audience are offended then you need to take note of the feedback. If your presentation is designed to appeal to your friends and relatives then again you are making it all about you not about the audience.
Also when giving a public lecture you have to keep in mind the fact that even if you are famous in some field the majority of the audience won’t know much about you. The majority of the audience are not friends who have some background knowledge which helps them interpret your actions, and they aren’t people who have seen your previous lectures. Your lecture has to stand alone. Any defense of a talk which is badly received which involves a phrase such as “if you knew him better” or “if you had seen his other talks” is a weak defense. In almost all cases the audience should be expected to have no prior knowledge of the speaker.
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