Older blog entries for etbe (starting at number 1143)

Being Obviously Wrong About Autism

I’m watching a Louis Theroux documentary about Autism (here’s the link to the BBC web site [1]). The main thing that strikes me so far (after watching 7.5 minutes of it) is the bad designed of the DLC-Warren school for Autistic kids in New Jersey [2].

A significant portion of people on the Autism Spectrum have problems with noisy environments, whether most Autistic people have problems with noise depends on what degree of discomfort is considered a problem. But I think it’s most likely to assume that the majority of kids on the Autism Spectrum will behave better in a quiet environment. So any environment that is noisy will cause more difficult behavior in most Autistic kids and the kids who don’t have problems with the noise will have problems with the way the other kids act. Any environment that is more prone to noise pollution than is strictly necessary is hostile to most people on the Autism Spectrum and all groups of Autistic people.

The school that is featured in the start of the documentary is obviously wrong in this regard. For starters I haven’t seen any carpet anywhere. Carpeted floors are slightly more expensive than lino but the cost isn’t significant in terms of the cost of running a special school (such schools are expensive by private-school standards). But carpet makes a significant difference to ambient noise.

Most of the footage from that school included obvious echos even though they had an opportunity to film when there was the least disruption – presumably noise pollution would be a lot worse when a class finished.

It’s not difficult to install carpet in all indoor areas in a school. It’s also not difficult to install rubber floors in all outdoor areas in a school (it seems that most schools are doing this already in play areas for safety reasons). For a small amount of money spent on installing and maintaining noise absorbing floor surfaces the school could achieve better educational results. The next step would be to install noise absorbing ceiling tiles and wallpaper, that might be a little more expensive to install but it would be cheap to maintain.

I think that the hallways in a school for Autistic kids should be as quiet as the lobby of a 5 star hotel. I don’t believe that there is any technical difficulty in achieving that goal, making a school look as good as an expensive hotel would be expensive but giving it the same acoustic properties wouldn’t be difficult or expensive.

How do people even manage to be so wrong about such things? Do they never seek any advice from any adult on the Autism Spectrum about how to run their school? Do they avoid doing any of the most basic Google searches for how to create a good environment for Autistic people? Do they just not care at all and create an environment that looks good to NTs? If they are just trying to impress NTs then why don’t they have enough pride to care that people like me will know how bad they are? These aren’t just rhetorical questions, I’d like to know what’s wrong with those people that makes them do their jobs in such an amazingly bad way.

Related posts:

  1. Autism, Food, etc James Purser wrote “Stop Using Autism to Push Your Own...
  2. Autism and a Child Beauty Contest Fenella Wagener wrote an article for the Herald Sun about...
  3. Autism Awareness and the Free Software Community It’s Autism Awareness Month April is Autism Awareness month, there...

Syndicated 2014-08-09 16:01:46 from etbe - Russell Coker

Booting GPT

I’m installing new 4TB disks on an older Dell server, it’s a PowerEdge T110 with a G6950 CPU so it’s not really old, but it’s a couple of generations behind the latest Dell servers.

I tried to enable UEFI booting, but when I turned that option on the system locked up during the BIOS process (wouldn’t boot from the CD or take keyboard input). So I had to make it boot with a BIOS compatible MBR and a GPT partition table.

Number  Start (sector)    End (sector)  Size      Code  Name
  1            2048            4095  1024.0 KiB  EF02  BIOS boot partition
  2            4096        25169919  12.0 GiB    FD00  Linux RAID
  3        25169920      7814037134  3.6 TiB    8300  Linux filesystem

After spending way to much time reading various web pages I discovered that the above partition table works. The 1MB partition is for GRUB code and needs to be enabled by a parted command such as the following:

parted /dev/sda set 1 bios_grub on

/dev/sda2 is a RAID-1 array used for the root filesystem. If I was installing a non-RAID system I’d use the same partition table but with a type of 8300 instead of FD00. I have a RAID-1 array over sda2 and sdb2 for the root filesystem and sda3, sdb3, sdc3, sdd3, and sde3 are used for a RAID-Z array. I’m reserving space for the root filesystem on all 5 disks because it seems like a good idea to use the same partition table and the 12G per disk that is unused on sdc, sdd, and sde isn’t worth worrying about when dealing with 4TB disks.

Related posts:

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  3. Resizing the Root Filesystem Uwe Hermann has described how to resize a root filesystem...

Syndicated 2014-08-06 06:53:34 from etbe - Russell Coker

More BTRFS Fun

I wrote a BTRFS status report yesterday commenting on the uneventful use of BTRFS recently [1].

Early this morning the server that stores my email (which had 93 days uptime) had a filesystem related problem. The root filesystem became read-only and then the kernel message log filled with unrelated messages so there was no record of the problem. I’m now considering setting up rsyslogd to log the kernel messages to a tmpfs filesystem to cover such problems in future. As RAM is so cheap it wouldn’t matter if a few megs of RAM were wasted by that in normal operation if it allowed me to extract useful data when something goes really wrong. It’s really annoying to have a system in a state where I can login as root but not find out what went wrong.

After that I tried 2 kernels in the 3.14 series, both of which had kernel BUG assertions related to Xen networking and failed to network correctly, I filed Debian Bug #756714. Fortunately they at least had enough uptime for me to run a filesystem scrub which reported no errors.

Then I reverted to kernel 3.13.10 but the reboot to apply that kernel change failed. Systemd was unable to umount the root filesystem (maybe because of a problem with Xen) and then hung the system instead of rebooting, I filed Debian Bug #756725. I believe that if asked to reboot a system there is no benefit in hanging the system with no user space processes accessible. Here are some useful things that systemd could have done:

  1. Just reboot without umounting (like “reboot -nf” does).
  2. Pause for some reasonable amount of time to give the sysadmin a possibility of seeing the error and then rebooting.
  3. Go back to a regular runlevel, starting daemons like sshd.
  4. Offer a login prompt to allow the sysadmin to login as root and diagnose the problem.

Options 1, 2, and 3 would have saved me a bit of driving. Option 4 would have allowed me to at least diagnose the problem (which might be worth the drive).

Having a system on the other side of the city which has no remote console access just hang after a reboot command is not useful, it would be near the top of the list of things I don’t want to happen in that situation. The best thing I can say about systemd’s operation in this regard is that it didn’t make the server catch fire.

Now all I really know is that 3.14 kernels won’t work for my server, 3.13 will cause problems that no-one can diagnose due to lack of data, and I’m now going to wait for it to fail again. As an aside the server has ECC RAM and it’s hardware is known to be good, so I’m sure that BTRFS is at fault.

Related posts:

  1. BTRFS Status March 2014 I’m currently using BTRFS on most systems that I can...
  2. BTRFS Status April 2014 Since my blog post about BTRFS in March [1] not...
  3. BTRFS vs LVM For some years LVM (the Linux Logical Volume Manager) has...

Syndicated 2014-08-01 10:41:30 from etbe - Russell Coker

Links July 2014

Dave Johnson wrote an interesting article for Salon about companies ripping off the tax system by claiming that all their income is produced in low tax countries [1].

Seb Lee-Delisle wrote an insightful article about how to ask to get paid to speak [2]. I should do that.

Daniel Pocock wrote an informative article about the reConServer simple SIP conferencing server [3]. I should try it out, currently most people I want to conference with are using Google Hangouts, but getting away from Google is a good thing.

François Marier wrote an informative post about hardening ssh servers [4].

S. E. Smith wrote an interesting article “I Am Tired of Hearing Programmers Defend Gender Essentialism [5].

Bert Archer wrote an insightful article about lazy tourism [6]. His initial example of “love locks” breaking bridges was a bit silly (it’s not difficult to cut locks off a bridge) but his general point about lazy/stupid tourism is good.

Daniel Pocock wrote an insightful post about new developments in taxis, the London Taxi protest against Uber, and related changes [7]. His post convinced me that Uber is a good thing and should be supported. I checked the prices and unfortunately Uber is more expensive than normal taxis for my most common journey.

Cory Doctorow wrote an insightful article for The Guardian about the moral issues related to government spying [8].

The Verge has an interesting review of the latest Lytro Lightbox camera [9]. Not nearly ready for me to use, but interesting technology.

Prospect has an informative article by Kathryn Joyce about the Protestant child sex abuse scandal in the US [10]. Billy Graham’s grandson is leading the work to reform churches so that they protect children instead of pedophiles. Prospect also has an article by Kathryn Joyce about Christians home-schooling kids to try and program them to be zealots and how that hurts kids [11].

The Daily Beast has an interesting article about the way that the extreme right wing in the US are trying to kill people, it’s the right wing death panel [12].

Jay Michaelson wrote an informative article for The Daily Beast about right-wing hate groups in the US who promote the extreme homophobic legislation in Russia and other countries [13]. It also connects to the Koch brothers who seem to be associated with most evil. Elias Isquith wrote an insightful article for Salon about the current right-wing obsession with making homophobic discrimination an issue of “religious liberty” will hurt religious people [14]. He also describes how stupid the right-wing extremists are in relation to other issues too.

EconomixComix.com has a really great comic explaning the economics of Social Security in the US [15]. They also have a comic explaining the TPP which is really good [16]. They sell a comic book about economics which I’m sure is worth buying. We need to have comics explaining all technical topics, it’s a good way of conveying concepts. When I was in primary school my parents gave me comic books covering nuclear physics and other science topics which were really good.

Mia McKenzie wrote an insightful article for BlackGirlDangerous.com about dealing with racist white teachers [17]. I think that it would be ideal to have a school dedicated to each minority group with teachers from that group.

Related posts:

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  3. Links June 2014 Russ Albery wrote an insightful blog post about trust, computer...

Syndicated 2014-07-31 13:38:53 from etbe - Russell Coker

BTRFS Status July 2014

My last BTRFS status report was in April [1], it wasn’t the most positive report with data corruption and system hangs. Hacker News has a brief discussion of BTRFS which includes the statement “Russell Coker’s reports of his experiences with BTRFS give me the screaming heebie-jeebies, no matter how up-beat and positive he stays about it” [2] (that’s one of my favorite comments about my blog).

Since April things have worked better. Linux kernel 3.14 solves the worst problems I had with 3.13 and it’s generally doing everything I want it to do. I now have cron jobs making snapshots as often as I wish (as frequently as every 15 minutes on some systems), automatically removing snapshots (removing 500+ snapshots at once doesn’t hang the system), balancing, and scrubbing. The fact that I can now expect that a filesystem balance (which is a type of defragment operation for BTRFS that frees some “chunks”) from a cron job and expect the system not to hang means that I haven’t run out of metadata chunk space. I expect that running out of metadata space can still cause filesystem deadlocks given a lack of reports on the BTRFS mailing list of fixes in that regard, but as long as balance works well we can work around that.

My main workstation now has 35 days of uptime and my home server has 90 days of uptime. Also the server that stores my email now has 93 days uptime even though it’s running Linux kernel 3.13.10. I am rather nervous about the server running 3.13.10 because in my experience every kernel before 3.14.1 had BTRFS problems that would cause system hangs. I don’t want a server that’s an hour’s drive away to hang…

The server that runs my email is using kernel 3.13.10 because when I briefly tried a 3.14 kernel it didn’t work reliably with the Xen kernel 4.1 from Debian/Wheezy and I had a choice of using the Xen kernel 4.3 from Debian/Unstable to match the Linux kernel or use an earlier Linux kernel. I have a couple of Xen servers running Debian/Unstable for test purposes which are working well so I may upgrade my mail server to the latest Xen and Linux kernels from Unstable in the near future. But for the moment I’m just not doing many snapshots and never running a filesystem scrub on that server.

Scrubbing

In kernel 3.14 scrub is working reliably for me and I have cron jobs to scrub filesystems on every system running that kernel. So far I’ve never seen it report an error on a system that matters to me but I expect that it will happen eventually.

The paper “An Analysis of Data Corruption in the Storage Stack” from the University of Wisconsin (based on NetApp data) [3] shows that “nearline” disks (IE any disks I can afford) have an incidence of checksum errors (occasions when the disk returns bad data but claims it to be good) of about 0.42%. There are 18 disks running in systems I personally care about (as opposed to systems where I am paid to care) so with a 0.42% probability of a disk experiencing data corruption per year that would give a 7.3% probability of having such corruption on one disk in any year and a greater than 50% chance that it’s already happened over the last 10 years. Of the 18 disks in question 15 are currently running BTRFS. Of the 15 running BTRFS 10 are scrubbed regularly (the other 5 are systems that don’t run 24*7 and the system running kernel 3.13.10).

Newer Kernels

The discussion on the BTRFS mailing list about kernel 3.15 is mostly about hangs. This is correlated with some changes to improve performance so I presume that it has exposed race conditions. Based on those discussions I haven’t felt inclined to run a 3.15 kernel. As the developers already have some good bug reports I don’t think that I could provide any benefit by doing more testing at this time. I think that there would be no benefit to me personally or the Linux community in testing 3.15.

I don’t have a personal interest in RAID-5 or RAID-6. The only systems I run that have more data than will fit on a RAID-1 array of cheap SATA disks are ones that I am paid to run – and they are running ZFS. So the ongoing development of RAID-5 and RAID-6 code isn’t an incentive for me to run newer kernels. Eventually I’ll test out RAID-6 code, but at the moment I don’t think they need more bug reports in this area.

I don’t have a great personal interest in filesystem performance at this time. There are some serious BTRFS performance issues. One problem is that a filesystem balance and subtree removal seem to take excessive amounts of CPU time. Another is that there isn’t much support for balancing IO to multiple devices (in RAID-1 every process has all it’s read requests sent to one device). For large-scale use of a filesystem these are significant problems. But when you have basic requirements (such as a mail server for dozens of users or a personal workstation with a quad-core CPU and fast SSD storage) it doesn’t make much difference. Currently all of my systems which use BTRFS have storage hardware that exceeds the system performance requirements by such a large margin that nothing other than installing Debian packages can slow the system down. So while there are performance improvements in newer versions of the BTRFS kernel code that isn’t an incentive for me to upgrade.

It’s just been announced that Debian/Jessie will use Linux 3.16, so I guess I’ll have to test that a bit for the benefit of Debian users. I am concerned that 3.16 won’t be stable enough for typical users at the time that Jessie is released.

Related posts:

  1. BTRFS Status March 2014 I’m currently using BTRFS on most systems that I can...
  2. BTRFS Status April 2014 Since my blog post about BTRFS in March [1] not...
  3. Starting with BTRFS Based on my investigation of RAID reliability [1] I have...

Syndicated 2014-07-31 10:45:10 from etbe - Russell Coker

Android Screen Saving

Just over a year ago I bought a Samsung Galaxy Note 2 [1]. About 3 months ago I noticed that some of the Ingress menus had burned in to the screen. Back in ancient computer times there were “screen saver” programs that blanked the screen to avoid this, then the “screen saver” programs transitioned to displaying a variety of fancy graphics which didn’t really fulfill the purpose of saving the screen. With LCD screens I have the impression that screen burn wasn’t an issue, but now with modern phones we have LED displays which have the problem again.

Unfortunately there doesn’t seem to be a free screen-saver program for Android in the Google Play store. While I can turn the screen off entirely there are some apps such as Ingress that I’d like to keep running while the screen is off or greatly dimmed. Now I sometimes pull the notification menu down when I’m going to leave Ingress idle for a while, this doesn’t stop the screen burning but it does cause different parts to burn which alleviates the problem.

It would be nice if apps were designed to alleviate this. A long running app should have an option to change the color of it’s menus, it would be ideal to randomly change the color on startup. If the common menus such as the “COMM” menu would appear in either red, green, or blue (the 3 primary colors of light) in a ratio according to the tendency to burn (blue burns fastest so should display least) then it probably wouldn’t cause noticable screen burn after 9 months. The next thing that they could do is to slightly vary the position of the menus, instead of having a thin line that’s strongly burned into the screen there would be a fat line lightly burned in which should be easier to ignore.

It’s good when apps have an option of a “dark” theme, that involves less light coming from the screen that should reduce battery use and screen burn. A dark theme should be at least default and probably mandatory for long running apps, a dark theme is fortunately the only option for Ingress.

I am a little disappointed with my phone. I’m not the most intensive Ingress player so I think that the screen should have lasted for more than 9 months before being obviously burned.

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Syndicated 2014-07-29 12:28:51 from etbe - Russell Coker

Happiness and Lecture Questions

I just attended a lecture about happiness comparing Australia and India at the Australia India Institute [1]. The lecture was interesting but the “questions” were so bad that it makes a good case for entirely banning questions from public lectures. Based on this and other lectures I’ve attended I’ve written a document about how to recognise worthless questions and cut them off early [2].

As you might expect from a lecture on happiness there were plenty of stupid comments from the audience about depression, as if happiness is merely the absence of depression.

Then they got onto stupidity about suicide. One “question” claimed that Australia has a high suicide rate, Wikipedia however places Australia 49th out of 110 countries, that means Australia is slightly above the median for suicide rates per country. Given some of the dubious statistics in the list (for example the countries claiming to have no suicides and the low numbers reported by some countries with extreme religious policies) I don’t think we can be sure that Australia would be above the median if we had better statistics. Another “question” claimed that Sweden had the highest suicide rate in Europe, while Greenland, Belgium, Finland, Austria, France, Norway, Denmark, Iceland, and most of Eastern Europe are higher on the list.

But the bigger problem in regard to discussing suicide is that the suicide rate isn’t about happiness. When someone kills themself because they have a terminal illness that doesn’t mean that they were unhappy for the majority of their life and doesn’t mean that they were any unhappier than the terminally ill people who don’t do that. Some countries have a culture that is more positive towards suicide which would increase the incidence, Japan for example. While people who kill themselves in Japan are probably quite unhappy at the time I don’t think that there is any reason to believe that they are more unhappy than people in other countries who only keep living because suicide is considered to be wrong.

It seems to me that the best strategy when giving or MCing a lecture about a potentially contentious topic is to plan ahead for what not to discuss. For a lecture about happiness it would make sense to rule out all discussion of suicide, anti-depressants, and related issues as they aren’t relevant to the discussion and can’t be handled in an appropriate manner in question time.

Related posts:

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Syndicated 2014-07-29 10:57:37 from etbe - Russell Coker

Public Lectures About FOSS

Eventbrite

I’ve recently started using the Eventbrite Web site [1] and the associated Eventbrite Android app [2] to discover public events in my area. Both the web site and the Android app lack features for searching (I’d like to save alerts for my accounts and have my phone notify me when new events are added to their database) but it is basically functional. The main issue is content, Eventbrite has a lot of good events in their database (I’ve got tickets for 6 free events in the next month). I assume that Eventbrite also has many people attending their events, otherwise the events wouldn’t be promoted there.

At this time I haven’t compared Eventbrite to any similar services, Eventbrite events have taken up much of my available time for the next 6 weeks (I appreciate the button on the app to add an entry to my calendar) so I don’t have much incentive to find other web sites that list events. I would appreciate comments from users of competing event registration systems and may write a post in future comparing different systems. Also I have only checked for events in Melbourne, Australia as I don’t have any personal interest in events in other places. For the topic of this post Eventbrite is good enough, it meets all requirements for Melbourne and I’m sure that if it isn’t useful in other cities then there are competing services.

I think that we need to have free FOSS events announced through Eventbrite. We regularly have experts in various fields related to FOSS visiting Melbourne who give a talk for the Linux Users of Victoria (and sometimes other technical groups). This is a good thing but I think we could do better. Most people in Melbourne probably won’t attend a LUG meeting and if they did they probably wouldn’t find it a welcoming experience.

Also I recommend that anyone who is looking for educational things to do in Melbourne visit the Eventbrite web site and/or install the Android app.

Accessible Events

I recently attended an Eventbrite event where a professor described the work of his research team, it was a really good talk that made the topic of his research accessible to random members of the public like me. Then when it came to question time the questions were mostly opinion pieces disguised as questions which used a lot of industry specific jargon and probably lost the interest of most people in the audience who wasn’t from the university department that hosted the lecture. I spent the last 15 minutes in that lecture hall reading Wikipedia and resisted the temptation to load an Android game.

Based on this lecture (and many other lectures I’ve seen) I get the impression that when the speaker or the MC addresses a member of the audience by name (EG “John Smith has a question”) then it’s strongly correlated with a low quality question. See my previous post about the Length of Conference Questions for more on this topic [3].

It seems to me that when running a lecture everyone involved has to agree about whether it’s a public lecture (IE one that is for any random people) as opposed to a society meeting (which while free for anyone to attend in the case of a LUG is for people with specific background knowledge). For a society meeting (for want of a better term) it’s OK to assume a minimum level of knowledge that rules out some people. If 5% of the audience of a LUG don’t understand a lecture that doesn’t necessarily mean it’s a bad lecture, sometimes it’s not possible to give a lecture that is easily understood by those with the least knowledge that also teaches the most experienced members of the audience.

For a public lecture the speaker has to give a talk for people with little background knowledge. Then the speaker and/or the MC have to discourage or reject questions that are for a higher level of knowledge.

As an example of how this might work consider the case of an introductory lecture about how an OS kernel works. When one of the experienced Linux kernel programmers visits Melbourne we could have an Eventbrite event organised for a lecture introducing the basic concepts of an OS kernel (with Linux as an example). At such a lecture any questions about more technical topics (such as specific issues related to compilers, drivers, etc) could be met with “we are having a meeting for more technical people at the Linux Users of Victoria meeting tomorrow night” or “we are having coffee at a nearby cafe afterwards and you can ask technical questions there”.

Planning Eventbrite Events

When experts in various areas of FOSS visit Melbourne they often offer a talk for LUV. For any such experts who read this post please note that most lectures at LUV meetings are by locals who can reschedule, so if you are only in town for a short time we can give you an opportunity to speak at short notice.

I would like to arrange to have some of those people give a talk aimed at a less experienced audience which we can promote through Eventbrite. The venue for LUV talks (Melbourne University 7PM on the first Tuesday of the month) might not work for all speakers so we need to find a sponsor for another venue.

I will contact Linux companies that are active in Melbourne and ask whether they would be prepared to sponsor the venue for such a talk. The fallback option would be to have such a lecture at a LUV meeting.

I will talk to some of the organisers of science and technology events advertised on Eventbrite and ask why they chose the times that they did. Maybe they have some insight into which times are best for getting an audience. Also I will probably get some idea of the best times by just attending many events and observing the attendance. I think that the aim of an Eventbrite event is to attract delegates who wouldn’t attend other meetings, so it is a priority to choose a suitable time and place.

Finally please note that while I am a member of the LUV committee I’m not representing LUV in this post. My aim is that community feedback on this post will help me plan such events. I will discuss this with the LUV committee after I get some comments here.

Please comment if you would like to give such a public lecture, attend such a lecture, or if you just have any general ideas.

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Syndicated 2014-07-22 08:22:17 from etbe - Russell Coker

Improving Computer Reliability

In a comment on my post about Taxing Inferior Products [1] Ben pointed out that most crashes are due to software bugs. Both Ben and I work on the Debian project and have had significant experience of software causing system crashes for Debian users.

But I still think that the widespread adoption of ECC RAM is a good first step towards improving the reliability of the computing infrastructure.

Currently when software developers receive bug reports they always wonder whether the bug was caused by defective hardware. So when bugs can’t be reproduced (or can’t be reproduced in a way that matches the bug report) they often get put in a list of random crash reports and no further attention is paid to them.

When a system has ECC RAM and a filesystem that uses checksums for all data and metadata we can have greater confidence that random bugs aren’t due to hardware problems. For example if a user reports a file corruption bug they can’t repeat that occurred when using the Ext3 filesystem on a typical desktop PC I’ll wonder about the reliability of storage and RAM in their system. If however the same bug report came from someone who had ECC RAM and used the ZFS filesystem then I would be more likely to consider it a software bug.

The current situation is that every part of a typical PC is unreliable. When a bug can be attributed to one of several pieces of hardware, the OS kernel and even malware (in the case of MS Windows) it’s hard to know where to start in tracking down a bug. Most users have given up and accepted that crashing periodically is just what computers do. Even experienced Linux users sometimes give up on trying to track down bugs properly because it’s sometimes very difficult to file a good bug report. For the typical computer user (who doesn’t have the power that a skilled Linux user has) it’s much worse, filing a bug report seems about as useful as praying.

One of the features of ECC RAM is that the motherboard can inform the user (either at boot time, after a NMI reboot, or through system diagnostics) of the problem so it can be fixed. A feature of filesystems such as ZFS and BTRFS is that they can inform the user of drive corruption problems, sometimes before any data is lost.

My recommendation of BTRFS in regard to system integrity does have a significant caveat, currently the system reliability decrease due to crashes outweighs the reliability increase due to checksums at this time. This isn’t all bad because at least when BTRFS crashes you know what the problem is, and BTRFS is rapidly improving in this regard. When I discuss BTRFS in posts like this one I’m considering the theoretical issues related to the design not the practical issues of software bugs. That said I’ve twice had a BTRFS filesystem seriously corrupted by a faulty DIMM on a system without ECC RAM.

Related posts:

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Syndicated 2014-07-11 04:51:55 from etbe - Russell Coker

A Linux Conference as a Ritual

Sociological Images has an interesting post by Jay Livingston PhD about a tennis final as a ritual [1]. The main point is that you can get a much better view of the match on your TV at home with more comfort and less inconvenience, so what you get for the price of the ticket (and all the effort of getting there) is participating in the event as a spectator.

It seems to me that the same idea applies to community Linux conferences (such as LCA) and some Linux users group meetings. In terms of watching a lecture there are real benefits to downloading it after the conference so that you can pause it and study related web sites or repeat sections that you didn’t understand. Also wherever you might sit at home to watch a video of a conference lecture you will be a lot more comfortable than a university lecture hall. Some people don’t attend conferences and users’ group meetings because they would rather watch a video at home.

Benefits of Attending (Apart from a Ritual)

One of the benefits of attending a lecture is the ability to ask questions. But that seems to mostly apply to the high status people who ask most questions. I’ve previously written about speaking stacks and my observations about who asks questions vs the number that can reasonably be asked [2].

I expect that most delegates ask no questions for the entire conference. I created a SurveyMonkey survey to discover how many questions people ask [3]. I count LCA as a 3 day conference because I am only counting the days where there are presentations that have been directly approved by the papers committee, approving a mini-conf (and thus delegating the ability to approve speeches) is different.

Another benefit of attending is the so-called “hallway track” where people talk to random other people. But that seems to be of most benefit to people who have some combination of high status in the community and good social skills. In the past I’ve attended the “Professional Delegates Networking Session” which is an event for speakers and people who pay the “Professional” registration fee. Sometimes at such events there has seemed to be a great divide between speakers (who mostly knew each other before the conference) and “Professional Delegates” which diminishes the value of the event to anyone who couldn’t achieve similar benefits without it.

How to Optimise a Conference as a Ritual

To get involvement of people who have the ritualistic approach one could emphasise the issue of being part of the event. For example to get people to attend the morning keynote speeches (which are sometimes poorly attended due to partying the night before) one could emphasise that anyone who doesn’t attend the keynote isn’t really attending the conference.

Conference shirts seem to be strongly correlated with the ritual aspect of conferences, the more “corporate” conferences don’t seem to offer branded clothing to delegates. If an item of branded schwag was given out before each keynote then that would increase the attendance by everyone who follows the ritual aspect (as well as everyone who just likes free stuff).

Note that I’m not suggesting that organisers of LCA or other conferences go to the effort of giving everyone schwag before the morning keynote, that would be a lot of work. Just telling people that anyone who misses the keynote isn’t really attending the conference would probably do.

I’ve always wondered why conference organisers want people to attend the keynotes and award prizes to random delegates who attend them. Is a keynote lecture a ritual that is incomplete if the attendance isn’t good enough?

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Syndicated 2014-07-10 08:00:28 from etbe - Russell Coker

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