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I had a problem with my mouse. The slippery plastic bits on the bottom weren’t glued on well and came off, which then gave more friction when moving on the desk. After asking advice on a mailing list the best suggestion was Teflon sticky tape. I bought a few meters of such tape (a lifetime supply for mouse repair) and used an 8cm strip on each side of the bottom of my mouse which made it slippery enough.
Ebay seems like a good place to buy that, most of the offers are well below $20 for a reel of tape including postage. One thing to note is that they also sell non-adhesive teflon tape. I made the mistake of investigating the capabilities of teflon tape then buying the cheapest one on offer which turned out to be “plumber’s tape” which doesn’t have adhesive, fortunately it was well below $10. I now have a lifetime supply of plumber’s tape if I can ever find a use for it.
Based on a comment from my previous post [1] I have named the new FOSS group for Australia and NZ Flounder. Here is the link to the agenda for the first meeting [2].
I am currently using a DNS name in my own domain for the group, but in the near future I’ll move it to somewhere else under a zone I don’t control. My aim is not to have personal control but to create an organisation for the community. But at the moment I’m just doing things in the fastest way possible, I will setup HTTP redirects when I get a better DNS name.
Washington Post has an interesting article on how gender neutral language is developing in different countries [1].
pimaker has an interesting blog post about how they wrote a RISCV CPU emulator to boot a Linux kernel in a pixel shader in the VR Chat platform [2].
ZD has an interesting article about the new Solo Bumblebee platform for writing EBPF programs to run inside the Linux kernel [3]. EBPF is an interesting platform and it’s good to have new tools to help people develop for it.
Big Think has an interesting article about augmented reality suggesting that it could be worse than social media for driving disputes [4]. Some people would want tags of racial status on all people they see.
Vice has an insightful article making the case for 8 hours of work per week [5].
The Guardian has an insightful article about how our attention is being stolen by modern technology [6].
Interesting article about the Ilobleed rootkit that targets the HP ILO server management system [7], it’s apparently designed for persistent attacks as it bypasses the firmware upgrade process and updates only the version number so anyone who thinks that a firmware update will fix it is horribly mislead.
Nick Bostrom wrote an insightful and disturbing article for Aeon titles None of Our Technologies has Managed to Destroy Humanity Yet [8] about the existential risk of new technologies and how they might be mitigated, much of which involves authoritarian governments unlike any we have seen before. As a counterpoint the novel A Deepness in the Sky claims that universal surveillance would be as damaging to the future of a society as planet-buster bombs.
Euronews has an informative article about eco-fascism [9]. The idea that the solution to ecological problems is to have less people in the world and particularly less non-white people is a gateway from green politics to fascism.
The developer of the colors and faker npm libraries (for NodeJS) recently uploaded corrupted versions of those libraries as a protest against companies that use them without paying him [10]. This is the wrong way to approach the issue, but it does demonstrate a serious problem with systems like NPM that allow automatic updates. It gives a better result to just use software packaged by a distribution which has QA checks applied including on security updates.
VentureBeat has an interesting article on the way that AI is taking over jobs [11]. Lots of white collar jobs can be replaced by machine learning systems, we need to plan for the ways this will change the economy.
The Atlantic has an interesting article about tapeworms that infect some ants [12]. The tapeworms make the ants live longer and produce pheromones to make the other ants serve them. This increases the chance that the ants will be eaten by birds which is the next stage in the tapeworm lifecycle.
I am going to start a new Linux focused FOSS online meeting for people in Australia and nearby areas. People can join from anywhere but the aim will be to support people in nearby areas.
To cover the time zone range for Australia this requires a meeting on a weekend, I’m thinking of the first Saturday of the month at 1PM Melbourne/Sydney time, that would be 10AM in WA and 3PM in NZ. We may have corner cases of daylight savings starting and ending on different days, but that shouldn’t be a big deal as I think those times can vary by an hour either way without being too inconvenient for anyone.
Note that I describe the meeting as Linux focused because my plans include having a meeting dedicated to different versions of BSD Unix and a meeting dedicated to the HURD. But those meetings will be mainly for Linux people to learn about other Unix-like OSs.
One focus I want to have for the meetings is hands-on work, live demonstrations, and short highly time relevant talks. There are more lectures on YouTube than anyone could watch in a lifetime (see the Linux.conf.au channel for some good ones [1]). So I want to run events that give benefits that people can’t gain from watching YouTube on their own.
Russell Stuart and I have been kicking around ideas for this for a while. I think that the solution is to just do it. I know that Saturday won’t work for everyone (no day will) but it will work for many people. I am happy to discuss changing the start time by an hour or two if that seems likely to get more people. But I’m not particularly interested in trying to make it convenient for people in Hawaii or India, my idea is for an Australia/NZ focused event. I would be more than happy to share lecture notes etc with people in other countries who run similar events. As an aside I’d be happy to give a talk for an online meeting at a Hawaiian LUG as the timezone is good for me.
Please pencil in 1PM Melbourne time on the 5th of Feb for the first meeting. The meeting requirements will be a PC with good Internet access running a recent web browser and a ssh client for the hands-on stuff. A microphone or webcam is NOT required, any questions you wish to ask can be done with text if that’s what you prefer.
Suggestions for the name of the group are welcome.
I previously wrote about the issue of swap potentially breaking SSD [1]. My conclusion was that swap wouldn’t be a problem as no normally operating systems that I run had swap using any significant fraction of total disk writes. In that post the most writes I could see was 128GB written per day on a 120G Intel SSD (writing the entire device once a day).
My post about swap and SSD was based on the assumption that you could get many thousands of writes to the entire device which was incorrect. Here’s a background on the terminology from WD [2]. So in the case of the 120G Intel SSD I was doing over 1 DWPD (Drive Writes Per Day) which is in the middle of the range of SSD capability, Intel doesn’t specify the DWPD or TBW (Tera Bytes Written) for that device.
The most expensive and high end NVMe device sold by my local computer store is the Samsung 980 Pro which has a warranty of 150TBW for the 250G device and 600TBW for the 1TB device [3]. That means that the system which used to have an Intel SSD would have exceeded the warranty in 3 years if it had a 250G device.
My current workstation has been up for just over 7 days and has averaged 110GB written per day. It has some light VM use and the occasional kernel compile, a fairly typical developer workstation. It’s storage is 2*Crucial 1TB NVMe devices in a BTRFS RAID-1, the NVMe devices are the old series of Crucial ones and are rated for 200TBW which means that they can be expected to last for 5 years under the current load. This isn’t a real problem for me as the performance of those devices is lower than I hoped for so I will buy faster ones before they are 5yo anyway.
My home server (and my wife’s workstation) is averaging 325GB per day on the SSDs used for the RAID-1 BTRFS filesystem for root and for most data that is written much (including VMs). The SSDs are 500G Samsung 850 EVOs [4] which are rated at 150TBW which means just over a year of expected lifetime. The SSDs are much more than a year old, I think Samsung stopped selling them more than a year ago. Between the 2 SSDs SMART reports 18 uncorrectable errors and “btrfs device stats” reports 55 errors on one of them. I’m not about to immediately replace them, but it appears that they are well past their prime.
The server which runs my blog (among many other things) is averaging over 1TB written per day. It currently has a RAID-1 of hard drives for all storage but it’s previous incarnation (which probably had about the same amount of writes) had a RAID-1 of “enterprise” SSDs for the most written data. After a few years of running like that (and some time running with someone else’s load before it) the SSDs became extremely slow (sustained writes of 15MB/s) and started getting errors. So that’s a pair of SSDs that were burned out.
Conclusion
The amounts of data being written are steadily increasing. Recent machines with more RAM can decrease storage usage in some situations but that doesn’t compare to the increased use of checksummed and logged filesystems, VMs, databases for local storage, and other things that multiply writes. The amount of writes allowed under warranty isn’t increasing much and there are new technologies for larger SSD storage that decrease the DWPD rating of the underlying hardware.
For the systems I own it seems that they are all going to exceed the rated TBW for the SSDs before I have other reasons to replace them, and they aren’t particularly high usage systems. A mail server for a large number of users would hit it much earlier.
RAID of SSDs is a really good thing. Replacement of SSDs is something that should be planned for and a way of swapping SSDs to less important uses is also good (my parents have some SSDs that are too small for my current use but which work well for them). Another thing to consider is that if you have a server with spare drive bays you could put some extra SSDs in to spread the wear among a larger RAID-10 array. Instead of having a 2*SSD BTRFS RAID-1 for a server you could have 6*SSD to get a 3* longer lifetime than a regular RAID-1 before the SSDs wear out (BTRFS supports this sort of thing).
Based on these calculations and the small number of errors I’ve seen on my home server I’ll add a 480G SSD I have lying around to the array to spread the load and keep it running for a while longer.
I’ve just done a tech check for my LCA lecture. I had initially planned to do what I had done before and use my phone for recording audio and video and my PC for other stuff. The problem is that I wanted to get an external microphone going and plugging in a USB microphone turned off the speaker in the phone (it seemed to direct audio to a non-existent USB audio output). I tried using bluetooth headphones with the USB microphone and that didn’t work. Eventually a viable option seemed to be using USB headphones on my PC with the phone for camera and microphone. Then it turned out that my phone (Huawei Mate 10 Pro) didn’t support resolutions higher than VGA with Chrome (it didn’t have the “advanced” settings menu to select resolution), this is probably an issue of Android build features. So the best option is to use a webcam on the PC, I was recommended a Logitech C922 but OfficeWorks only has a Logitech C920 which is apparently OK.
The free connection test from freeconference.com [1] is good for testing out how your browser works for videoconferencing. It tests each feature separately and is easy to run.
After buying the C920 webcam I found that it sometimes worked and sometimes caused a kernel panic like the following (partial panic log included for the benefit of people Googling this Logitech C920 problem):
[95457.805417] BUG: kernel NULL pointer dereference, address: 0000000000000000
[95457.805424] #PF: supervisor read access in kernel mode
[95457.805426] #PF: error_code(0x0000) - not-present page
[95457.805429] PGD 0 P4D 0
[95457.805431] Oops: 0000 [#1] SMP PTI
[95457.805435] CPU: 2 PID: 75486 Comm: v4l2src0:src Not tainted 5.15.0-2-amd64 #1 Debian 5.15.5-2
[95457.805438] Hardware name: HP ProLiant ML110 Gen9/ProLiant ML110 Gen9, BIOS P99 02/17/2017
[95457.805440] RIP: 0010:usb_ifnum_to_if+0x3a/0x50 [usbcore]
...
[95457.805481] Call Trace:
[95457.805484]
[95457.805485] usb_hcd_alloc_bandwidth+0x23d/0x360 [usbcore]
[95457.805507] usb_set_interface+0x127/0x350 [usbcore]
[95457.805525] uvc_video_start_transfer+0x19c/0x4f0 [uvcvideo]
[95457.805532] uvc_video_start_streaming+0x7b/0xd0 [uvcvideo]
[95457.805538] uvc_start_streaming+0x2d/0xf0 [uvcvideo]
[95457.805543] vb2_start_streaming+0x63/0x100 [videobuf2_common]
[95457.805550] vb2_core_streamon+0x54/0xb0 [videobuf2_common]
[95457.805555] uvc_queue_streamon+0x2a/0x40 [uvcvideo]
[95457.805560] uvc_ioctl_streamon+0x3a/0x60 [uvcvideo]
[95457.805566] __video_do_ioctl+0x39b/0x3d0 [videodev]
It turns out that Ubuntu Launchpad bug #1827452 has great information on this problem [2]. Apparently if the device decides it doesn’t have enough power then it will reconnect and get a different USB bus device number and this often happens when the kernel is initialising it. There’s a race condition in the kernel code in which the code to initialise the device won’t realise that the device has been detached and will dereference a NULL pointer and then mess up other things in USB device management. The end result for me is that all USB devices become unusable in this situation, commands like “lsusb” hang, and a regular shutdown/reboot hangs because it can’t kill the user session because something is blocked on USB.
One of the comments on the Launchpad bug is that a powered USB hub can alleviate the problem while a USB extension cable (which I had been using) can exacerbate it. Officeworks currently advertises only one powered USB hub, it’s described as “USB 3” but also “maximum speed 480 Mbps” (USB 2 speed). So basically they are selling a USB 2 hub for 4* the price that USB 2 hubs used to sell for.
When debugging this I used the “cheese” webcam utility program and ran it in a KVM virtual machine. The KVM parameters “-device qemu-xhci -usb -device usb-host,hostbus=1,hostaddr=2” (where 1 and 2 are replaced by the Bus and Device numbers from “lsusb”) allow the USB device to be passed through to the VM. Doing this meant that I didn’t have to reboot my PC every time a webcam test failed.
For audio I’m using the Sades Wand gaming headset I wrote about previously [3].
The Tom Clancy book Debt of Honor published in August 1994 first introduced the concept of a heavy passenger aircraft being used as a weapon by terrorists against a well defended building. In April 1994 there was an attempt to hijack and deliberately crash FedEx flight 705. It’s possible for a book to be changed 4 months before publication, but it seems unlikely that a significant plot point in a series of books was changed in such a small amount of time so it’s likely that Tom Clancy got the idea first. There have been other variations on that theme, such as the Yokosuka_MXY-7 Kamakazi flying bomb (known by the Allies as “Baka” which is Japanese for idiot). But Tom Clancy seemed to pioneer the idea of a commercial passenger jet being subverted for the purpose of ground attack.
7 years after Tom Clancy’s book was published the 911 hijackings happened.
The TV series Black Mirror first aired in 2011, and the first episode was about terrorists kidnapping a princess and demanding that the UK PM perform an indecent act with a pig for her release. While the plot was a little extreme (the entire series is extreme) the basic concept of sexual extortion based on terrorist acts is something that could be done in real life, and if terrorists were inspired by this they are taking longer than expected to do it.
Most democracies seem to end up with two major parties that are closely matched. Even if a government was strict about not negotiating with terrorists it seems likely that terrorists demanding that a politician perform an unusual sex act on TV would change things, supporters would be divided into groups that support and oppose negotiating. Discussions wouldn’t be as civil as when the negotiation involves money or freeing prisoners. If an election result was perceived to have been influenced by such terrorism then supporters of the side that lost would claim it to be unfair and reject the result. If the goal of terrorists was to cause chaos then that would be one way of achieving it, and they have had over 10 years to consider this possibility.
Are we overdue for a terror attack inspired by Black Mirror?
Recently a relative who owned a 50″ Plasma TV asked me for advice on getting a new TV. Looking at the options all the TVs seem to be smart TVs (running Android with built in support for YouTube and Netflix) and most of them seem to be 4K resolution. 4K doesn’t provide much benefit now as most people don’t have BlueRay DVD players and discs, there aren’t a lot of 4K YouTube videos, and most streaming services don’t offer 4K resolution. But as 4K doesn’t cost much more it doesn’t make sense not to get it.
I gave my relative a list of good options from Kogan (the Australian company that has the cheapest consumer electronics) and they chose a 65″ 4K Smart TV from Kogan. That only cost $709 plus delivery which is reasonably affordable for something that will presumably last for a long time and be used by many people.
Netflix on a web browser won’t do more than FullHD resolution unless you use Edge on Windows 10. But Netflix on the smart tv has a row advertising 4K shows which indicates that 4K is supported. There are some 4K videos on YouTube but not a lot at this time.
Size
It turns out that 65″ is very big. It didn’t fit on the table that had been used for the 50″ Plasma TV.
Rtings.com has a good article about TV size vs distance [1]. According to their calculations if you want to sit 2 meters away from a TV and have a 30 degree field of view (recommended for “mixed” use) then a 45″ TV is ideal.
According to their calculations on pixel sizes, if you have a FullHD display (or the common modern case a FullHD signal displayed on a 4K monitor) that is between 1.8 and 2.5 meters away from you then a 45″ TV is the largest that will be useful. To take proper advantage of a monitor larger than 45″ at a distance of 2 meters you need a 4K signal. If you have a 4K signal then you can get best results by having a 45″ monitor less than 1.8 meters away from you. As most TV watching involves less than 3 people it shouldn’t be inconvenient to be less than 1.8 meters away from the TV.
The 65″ TV weighs 21Kg according to the specs, that isn’t a huge amount for something small, but for something a large and inconvenient as a 65″ TV it’s impossible for one person to safely move. Kogan sells 43″ TVs that weigh 6KG, that’s something that most adults could move with one hand. I think that a medium size TV that can be easily moved to a convenient location would probably give an equivalent viewing result to an extremely large TV that can’t be moved at all. I currently have a 40″ LCD TV, the only reason I have that is because a friend didn’t need it, the previous 32″ TV that I used was adequate for my needs. Most of my TV viewing is on a 28″ monitor, which I find adequate for 2 or 3 people. So I generally wouldn’t recommend a 65″ TV for anyone.
Android for TVs
Android wasn’t designed for TVs and doesn’t work that well on them. Having buttons on the remote for Netflix and YouTube is handy, but it would be nice if there were programmable buttons for other commonly used apps or a way to switch between the last few apps (like ALT-TAB on a PC).
One good feature of Android for TV is that it can display a set of rows of shows (similar to the Netflix method of displaying) where each row is from a different app. The apps I’ve installed on that TV which support the row view are Netflix, YouTube, YouTube Music, ABC iView (that’s Australian ABC), 7plus, 9now, and SBS on Demand. That’s nice, now we just need channel 10’s app to support that to have coverage for all Australian free TV stations in the Android TV interface.
Conclusion
It’s a nice TV and it generally works well. Android is OK for TV use but far from great. It is running Android version 9, maybe a newer version of Android works better on TVs.
It’s too large for reasonable people to use in a home. I’ve seen smaller TVs used for 20 people in an office in a video conference. It’s cheap enough that most people can afford it, but it’s easier and more convenient to have something smaller and lighter.
I have recently signed up for the Curiosity Stream [1] documentary site, this is designed to be like Netflix but for non-fiction content only. The service costs $US15 per annum or $52US per annum for 4K (I think the 4K service was about $US120 per annum when I signed up). The extra price for 4K seems excessive, while it is in line with the bandwidth requirements a large portion of the costs of the service would be about user support and running the service reliably for which 4K makes little difference.
My aim in subscribing was to just get a service like Netflix with new documentary content as I have watched every documentary I want to watch on Netflix (I think I’ve watched over 1000 hours of Netflix documentaries). So naturally I compare the service to Netflix and I found that it doesn’t compare well. Curiosity Stream (CS) has no button to skip the intro and has a problem with using the right arrow to skip forward (seems to only work once and then I have to use the mouse), this costs me about 30 seconds for each episode which adds up when watching documentaries at 1.5* speed. The method of controlling the viewing is a little clunky, sometimes the popup menu at the bottom of the screen to control playback doesn’t disappear by itself until you mouse over it and space bar doesn’t select pause instead it selects the last action. CS allows selecting individual episodes for your watch list instead of entire series, this could be useful for some people but I just find it annoying, it might be good for classroom use. The method of searching for new shows to watch isn’t as good as the Netflix method or the way things are displayed on Android TV (which seems to have an API for multiple video providers to show a list of shows with one row per provider). Some of these things might seem OK if you haven’t used other services, but if you are used to Netflix and Amazon Prime then it will seem clunky.
The amount of content on Curiosity Stream doesn’t seem that large, I don’t know how to get a full measure of it, but when I search for things I seem to get less results than on Netflix. That could be something to do with what I’m searching for.
In terms of value for money $US15 per annum for the content that CS provides is a good deal. Netflix overall offers better value for home users having fiction as well as non-fiction in large quantities. But for documentary content $US15 per annum is pretty cheap. I recommend signing up for CS, but for most people signing up for Netflix first will be a good option.
- [1] https://curiositystream.com/
Wired magazine has many short documentary films on YouTube, this one about How Photography is Affecting Our Brains is particularly good [1].
Matt Blaze wrote an informative blog post about Faraday cages for phones [2]. It seems that the commercial shielded bags are all pretty good while doing it yourself with aluminium foil may get similar results or may get much worse results with no obvious difference in the quality of the wrapping. Aluminium foil doesn’t protect that well and doesn’t protect consistently. A metal biscuit tin performed quite well and consistently, so that’s a cheap option for reducing signals.
Umair Haque wrote an insightful article about the single word that describes most of the problems the world faces right now [3].
Forbes has an informative article about the early days of the Ford company when they doubled wages, it proves that they didn’t do so to enable workders to afford cars but to avoid staff turnover (which is expensive) [4]. Also the Ford company had a fascistic approach to employees, controlling what they were allowed to do in their spare time if they wanted the bonus payment. The wages weren’t doubled, there was a bonus payment that would double the salary if the employee was eligible for the bonus. One thing that Forbes gets wrong is that they claim that it was only having higher pay than other companies that provided a benefit and that a higher minimum wage wouldn’t, the problem with that idea is that a higher minimum wage would discourage people from having multiple jobs and allow more families to not have the mother working (a condition for a man to get the Ford bonus was for his wife to not work).
The WSJ has an interesting article about Intel’s datacenter for running all the different configurations of CPUs that they have supported over the last 10 years for security tests [5]. My Thinkpad (which is less than 10yo) is vulnerable to one of the SPECTRE family of exploits as Intel hasn’t released microcode to fix it, getting fixed microcode out for all the systems from major vendors like Lenovo would be a good idea if they want to improve their security.
NPR has an interesting article about the correlation between support for Trump in counties of the US with lack of vaccination and Covid19 deaths [6]. No surprises, but it’s good to see the graphs.
Cory Doctorow wrote an interesting article on the lack of “slack” in the current American education system [7]. It’s not that bad in Australia but we are unfortunately moving in the American direction.
Teen Vogue has an insightful article about the problems with the focus on resilience [8], while resilience is good we should make it a higher priority to avoid putting people in situations where they need to be resiliant than on encouraging resilience.
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