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Linux Users of Victoria (LUV) Announce: LUV Main December 2015 Meeting: Maxima / holiday gifts

Fri, 2016-01-29 00:30
Start: Dec 1 2015 18:30 End: Dec 1 2015 20:30 Start: Dec 1 2015 18:30 End: Dec 1 2015 20:30 Location: 

6th Floor, 200 Victoria St. Carlton VIC 3053

Link:  http://luv.asn.au/meetings/map

Speakers:

• Chelton Evans, Maxima

• Andrew Pam, Holiday gift suggestions for Linux lovers

200 Victoria St. Carlton VIC 3053 (formerly the EPA building)

Late arrivals, please call (0490) 049 589 for access to the venue.

Before and/or after each meeting those who are interested are welcome to join other members for dinner. We are open to suggestions for a good place to eat near our venue. Maria's on Peel Street in North Melbourne is currently the most popular place to eat after meetings.

LUV would like to acknowledge Red Hat for their help in obtaining the venue and VPAC for hosting.

Linux Users of Victoria Inc. is an incorporated association, registration number A0040056C.

December 1, 2015 - 18:30

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Linux Users of Victoria (LUV) Announce: LUV Beginners November Meeting: Security scanning with Nmap

Fri, 2016-01-29 00:30
Start: Nov 21 2015 12:30 End: Nov 21 2015 16:30 Start: Nov 21 2015 12:30 End: Nov 21 2015 16:30 Location: 

RMIT Building 91, 110 Victoria Street, Carlton South

Link:  http://luv.asn.au/meetings/map

Scott Junner will offer a basic run through of the main functions of Nmap with some explanations of the background of what Nmap is doing and why it gets some of the results it gets. He will talk about why you would want to use Nmap and give an example of a few scans he did on his own network to show the kind of information that others could collect. Or you could collect on others - depending on which way you lean.

LUV would like to acknowledge Red Hat for their help in obtaining the Trinity College venue and VPAC for hosting.

Linux Users of Victoria Inc., is an incorporated association, registration number A0040056C.

November 21, 2015 - 12:30

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Linux Users of Victoria (LUV) Announce: LUV Main November 2015 Meeting: Computer Science and SELinux / Parallel Programming

Fri, 2016-01-29 00:30
Start: Nov 4 2015 18:30 End: Nov 4 2015 20:30 Start: Nov 4 2015 18:30 End: Nov 4 2015 20:30 Location: 

6th Floor, 200 Victoria St. Carlton VIC 3053

Link:  http://luv.asn.au/meetings/map

Please note that due to the Melbourne Cup this month's meeting is on Wednesday

Speakers:

• Russell Coker, Computer Science and SELinux

• Lev Lafayette, Parallel Programming

200 Victoria St. Carlton VIC 3053 (formerly the EPA building)

Late arrivals, please call (0490) 049 589 for access to the venue.

Before and/or after each meeting those who are interested are welcome to join other members for dinner. We are open to suggestions for a good place to eat near our venue. Maria's on Peel Street in North Melbourne is currently the most popular place to eat after meetings.

LUV would like to acknowledge Red Hat for their help in obtaining the venue and VPAC for hosting.

Linux Users of Victoria Inc. is an incorporated association, registration number A0040056C.

November 4, 2015 - 18:30

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Linux Users of Victoria (LUV) Announce: LUV Beginners October Meeting: Mail server installation training

Fri, 2016-01-29 00:30
Start: Oct 17 2015 12:30 End: Oct 17 2015 16:30 Start: Oct 17 2015 12:30 End: Oct 17 2015 16:30 Location: 

RMIT Building 91, 110 Victoria Street, Carlton South

Link:  http://luv.asn.au/meetings/map

This event is a hands-on lesson in installing a MTA (Mail Transfer Agent). It would be best to have a laptop, tablet, or phone with MUA (Mail User Agent) software installed. A basic knowledge of system administration is required. The work will probably be done in groups as it's likely that the number of people attending will exceed the number of virtual machines.

Russell Coker has done lots of Linux development over the years, mostly involved with Debian.

LUV would like to acknowledge Red Hat for their help in obtaining the Trinity College venue and VPAC for hosting.

Linux Users of Victoria Inc., is an incorporated association, registration number A0040056C.

October 17, 2015 - 12:30

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Linux Users of Victoria (LUV) Announce: Submission on Trans-Pacific Partnership

Fri, 2016-01-29 00:30

Status of the Submission



As of August 15 the Department of Foreign Affairs and Trade of the Commonwealth of Australia stated that it "continues to welcome public submissions and comments on Australia's participation in TPP negotiations: (http://dfat.gov.au/trade/agreements/tpp/submissions/Pages/submissions.aspx).

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Linux Users of Victoria (LUV) Announce: LUV Main October 2015 Meeting: Networking Fundamentals / High Performance Open Source Storage

Fri, 2016-01-29 00:30
Start: Oct 6 2015 18:30 End: Oct 6 2015 20:30 Start: Oct 6 2015 18:30 End: Oct 6 2015 20:30 Location: 

6th Floor, 200 Victoria St. Carlton VIC 3053

Link:  http://luv.asn.au/meetings/map

Speakers:

• Fraser McGlinn, Networking Fundamentals, Troubleshooting and Packet Analysis

• Sam McLeod, High Performance, Open Source Storage

200 Victoria St. Carlton VIC 3053 (formerly the EPA building)

Before and/or after each meeting those who are interested are welcome to join other members for dinner. We are open to suggestions for a good place to eat near our venue. Maria's on Peel Street in North Melbourne is currently the most popular place to eat after meetings.

LUV would like to acknowledge Red Hat for their help in obtaining the venue and VPAC for hosting.

Linux Users of Victoria Inc. is an incorporated association, registration number A0040056C.

October 6, 2015 - 18:30

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Linux Users of Victoria (LUV) Announce: Adjourned 2015 LUV Annual General Meeting

Fri, 2016-01-29 00:30
Start: Sep 19 2015 15:30 End: Sep 19 2015 16:15 Start: Sep 19 2015 15:30 End: Sep 19 2015 16:15 Location: 

Boardroom, Electron Workshop, 31 Arden Street, North Melbourne

Link:  http://www.electronworkshop.com.au/

Confirmation of adjourned LUV 2015 AGM

This notice is to confirm that Linux Users of Victoria Inc. will be holding the adjournment of its Annual General Meeting, on Saturday 19th September 2015. The meeting will be held in the Boardroom of Electron Workshop at 3.30pm.

Electron Workshop is on the south side of Arden Street, about half way between Errol Street and Leveson Street. Public transport: 57 tram, nearest stop at corner of Errol and Queensberry Streets; 55 and 59 trams run a few blocks away along Flemington Road; 402 bus runs along Arden Street, but nearest stop is on Errol Street. On a Saturday afternoon, some car parking should be available on nearby streets.

LUV would like to thank Electron Workshop for making their boardroom available for this meeting, also Red Hat for their help in obtaining the Trinity College venue and VPAC for hosting.

Linux Users of Victoria Inc., is an incorporated association, registration number A0040056C.

September 19, 2015 - 15:30

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Linux Users of Victoria (LUV) Announce: Software Freedom Day Meeting 2015

Fri, 2016-01-29 00:30
Start: Sep 19 2015 11:00 End: Sep 19 2015 16:00 Start: Sep 19 2015 11:00 End: Sep 19 2015 16:00 Location: 

Electron Workshop 31 Arden Street, North Melbourne.

Link:  http://www.sfd.org.au/melbourne/

There will not be a regular LUV Beginners workshop for the month of September. Instead, you're going to be in for a much bigger treat!

This month, Free Software Melbourne[1], Linux Users of Victoria[2] and Electron Workshop[3] are joining forces to bring you the local Software Freedom Day event for Melbourne.

The event will take place on Saturday 19th September between 11am and 4pm at:

Electron Workshop

31 Arden Street, North Melbourne.

Map: http://www.sfd.org.au/melbourne/

Electron Workshop is on the south side of Arden Street, about half way between Errol Street and Leveson Street. Public transport: 57 tram, nearest stop at corner of Errol and Queensberry Streets; 55 and 59 trams run a few blocks away along Flemington Road; 402 bus runs along Arden Street, but nearest stop is on Errol Street. On a Saturday afternoon, some car parking should be available on nearby streets.

LUV would like to acknowledge Red Hat for their help in obtaining the Trinity College venue and VPAC for hosting.

Linux Users of Victoria Inc., is an incorporated association, registration number A0040056C.

September 19, 2015 - 11:00

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Ben Martin: CNC Control with MQTT

Thu, 2016-01-28 21:22
I recently upgraded a 3040 CNC machine by replacing the parallel port driven driver board with a smoothieboard. This runs a 100Mhz Cortex-M mcu and has USB and ethernet interfaces, much more modern. This all lead me to coming up with a new controller to move the cutting head, all without needing to update the controller box or recompile or touch the smoothieboard firmware.







I built a small controller box with 12 buttons on it and shoved an esp8266 into that box with a MCP23017 chip to allow access to 16 gpio over TWI from the esp mcu. The firmware is fairly simple on the esp, it enables the internal pull ups on all gpio pins on the 23017 chip and sends an MQTT message when each button is pressed and released. The time since MCU boot in milliseconds is sent as the MQTT payload. This way, one can work out if this is a short or longer button press and move the cutting head a proportional distance.



The web interface for smoothie provides a pronterface like interface for manipulating where the cutting head is on the board and the height it is at. So lucky that it's open source firmware so I can see the non obfuscated javascript that the web interface uses. Then work out the correct POST method to send gcode commands directly to the smoothieboard on the CNC.



The interesting design here is using software on the server to make the controller box meet the smoothieboard. On the server MQTT messages are turned into POST requests using mqtt-launcher. The massive benefit here is that I can change what each button does on the CNC without needing to reprogram the controller or modify the cnc firmware. Just change the mqtt-launcher config file and all is well. So far MQTT is the best "IoT" tech I've had the privilege to use.







I'll probably build another controller for controlling 3d printers. Although most 3d printers just home each axis there is sometimes some pesky commands that must be run at startup, to help home z-axis for example. Having physical buttons to move the x axis down by 4mm, 1mm and 0.1mm makes it so much less likely to fat finger the web interface and accidentally crash the bed by initiating a larger z-axis movement than one had hoped for.

Russell Coker: Using LetsEncrypt

Thu, 2016-01-28 00:26

Lets Encrypt is a new service to provide free SSL keys [1]. I’ve just set it up on a few servers that I run.

Issues

The first thing to note is that the client is designed to manage your keys and treat all keys on a server equally with a single certificate. It shouldn’t be THAT difficult to do things in other ways but it would involve extra effort. The next issue that can make things difficult is that it is designed that the web server will have a module to negotiate new keys automatically. Automatically negotiating new keys will be really great when we get that all going, but as I didn’t feel like installing a slightly experimental Apache module on my servers that meant I had to stop Apache while I got the keys – and I’ll have to do that again every 3 months as the keys have a short expiry time.

There are some other ways of managing keys, but the web servers I’m using Lets Encrypt with at the moment aren’t that important and a couple of minutes of downtime is acceptable.

When you request multiple keys (DNS names) for one server to make it work without needless effort you have to get them all in the one operation. That gives you a single key file for all DNS names which is very convenient for services that don’t support getting the hostname before negotiating SSL. But it could be difficult if you wanted to have one of the less common configurations such as having a mail server and a web server on the same IP addess but using different keys

How To Get Keys

deb http://mirror.internode.on.net/pub/debian/ testing main

The letsencrypt client is packaged for Debian in Testing but not in Jessie. Adding the above to the /etc/apt/sources.list file for a Jessie system allows installing it and a few dependencies from Testing. Note that there are problems with doing this, you can’t be certain that all the other apps installed will be compatible with the newer versions of libraries that are installed and you won’t get security updates.

letsencrypt certonly --standalone-supported-challenges tls-sni-01

The above command makes the letsencrypt client listen on port 443 to talk to the Lets Encrypt server. It prompts you for server names so if you want to minimise the downtime for your web server you could specify the DNS names on the command-line.

If you run it on a SE Linux system you need to run “setsebool allow_execmem 1” before running it and “setsebool allow_execmem 0” afterwards as it needs execmem access. I don’t think it’s a problem to temporarily allow execmem access for the duration of running this program, if you use KDE then you will be forced to allow such access all the time for the desktop to operate correctly.

How to Install Keys

[ssl:emerg] [pid 9361] AH02564: Failed to configure encrypted (?) private key www.example.com:443:0, check /etc/letsencrypt/live/www.example.com/fullchain.pem

The letsencrypt client suggests using the file fullchain.pem which has the key and the full chain of certificates. When I tried doing that I got errors such as the above in my Apache error.log. So I gave up on that and used the separate files. The only benefit of using the fullchain.pem file is to have a single line in a configuration file instead of 3. Trying to debug issues with fullchain.pem took me a lot longer than copy/paste for the 3 lines.

Under /etc/letsencrypt/live/$NAME there are symlinks to the real files. So when you get new keys the old keys will be stored but the same file names can be used.

SSLCertificateFile "/etc/letsencrypt/live/www.example.com/cert.pem"

SSLCertificateChainFile "/etc/letsencrypt/live/www.example.com/chain.pem"

SSLCertificateKeyFile "/etc/letsencrypt/live/www.example.com/privkey.pem"

The above commands are an example for configuring Apache 2.

smtpd_tls_cert_file = /etc/letsencrypt/live/smtp.example.com/cert.pem

smtpd_tls_key_file = /etc/letsencrypt/live/smtp.example.com/privkey.pem

smtpd_tls_CAfile = /etc/letsencrypt/live/smtp.example.com/chain.pem

Above is an example of Postfix configuration.

ssl_cert = </etc/letsencrypt/live/smtp.example.com/cert.pem

ssl_key = </etc/letsencrypt/live/smtp.example.com/privkey.pem

ssl_ca = </etc/letsencrypt/live/smtp.example.com/chain.pem

Above is an example for Dovecot, it goes in /etc/dovecot/conf.d/10-ssl.conf in a recent Debian version.

Conclusion

At this stage using letsencrypt is a little fiddly so for some commercial use (where getting the latest versions of software in production is difficult) it might be a better option to just pay for keys. However some companies I’ve worked for have had issues with getting approval for purchases which would make letsencrypt a good option to avoid red tape.

When Debian/Stretch is released with letsencrypt I think it will work really well for all uses.

No related posts.

Lev Lafayette: Can processes survive after shutdown?

Wed, 2016-01-27 22:29

I had a process in a "uninterruptible sleep" state. Trying to kill it is, unsurprisingly, unhelpful. All the literature on the subject will say that it cannot be killed, and they're right. It's called "uninterruptible" for a reason. An uninterruptable process is in a system call that cannot be interrupted by a signal (such as a SIGKILL, SIGTERM etc).

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OpenSTEM: History and Geography for Primary program

Wed, 2016-01-27 14:30

OpenSTEM’s History and Geography for Primary program provides an integrated curriculum implementation, which aims to provide holistic learning for students in both Key Learning Areas. By integrating History and Geography, not only is the level of engagement higher, as students are able to gain a more rounded understanding of processes in places through time, but the time needed for teaching is optimised.

With complete lesson plans!

Australian Curriculum

The program is tailored exactly to the requirements of the Australian Curriculum so that all curriculum strands in both curricula are addressed efficiently. The focus is on providing a broad overview of global events and then focussing in on specific issues. A particular focal point, as determined by the Australian Curriculum, is Australian History, with Aboriginal History, sustainability and the environment as important foci as well.

Our Approach

Student engagement is the primary aim of this curriculum implementation and a range of activities ensure that learning takes place in a very hands-on and multimodal way.

Scientific research has identified that children are more engaged, with better retention of information, when a range of input stimuli are provided. In particular, visual and kinaesthetic methods of input have the broadest range of uptake of information in pre-puberty age groups. OpenSTEM’s blend of activities and resources addresses these methods directly.

The material is designed so as to provide for flexibility in use. Teachers can choose to utilise the individual resources within their own teaching framework, or they can choose to use the detailed weekly lesson plans as laid out in the Teacher Handbook. A Student Workbook is also provided, with a continual assessment option, to complete the package.

OpenSTEM uses particular techniques (such as coloured words within the text) which address a range of learning styles and have been shown to increase focus for students with concentration challenges.

Availability

The term 1 teacher units and supporting resources are now available, and already in use by some schools. Additional units and resources are made available progressively during this first year of this program, and updated thereafter.

You may purchase individual teacher units and resource PDFs, or subscribe (from an individual teacher or family to an entire school) and get the teacher units at half price and the resource PDFs for free!

You can also download some sample PDFs (at no cost, no login/details required) so that you are able to see and assess the quality of our materials. 

If you need more information and for any questions you may have, please contact us.

Cross-curricular options

OpenSTEM’s History and Geography program provides a range of cross-curricular options. In particular Science extensions are provided to address the Science curriculum. Some aspects of the Mathematics curriculum also follow naturally from this material.

These cross-curricular components help students apply newly learnt concepts and skills in a broader context.

Multi-Year-Level

OpenSTEM materials are designed to be adapted for use in multi-year level classrooms. Suggested implementations for multi-year level classes are provided in the Teacher Handbook for each unit.

In some cases the same resources and topics are used by different year levels and it is the depth of understanding and analysis required which is all that changes between the year levels. The Student Workbook for each unit reflects the differing requirements for different year levels. Using this structure, the teacher is not trying to teach different material simultaneously in order to meet the requirements of the National Curriculum.

Homeschoolers

Homeschooling parents also have great flexibility in their use of this material. The program is designed to be easily adaptable for the homeschooling situation. Parents can choose to use the resources within their own program, or allow the student to explore the material as their interest leads them. Alternatively, the parent can use the Teacher Handbook and Student Workbook to provide a series of lessons, knowing they will thus match all the curriculum requirements.

Non-linear learners can approach the student workbook in a non-linear fashion, referring to the matching resources as required in order to engage with the material. Using this material, the parent can tailor the learning to match the speed, abilities and particular challenges of each student.

The potential for extension and acceleration will suit students with those particular needs, whilst the shift between broad and narrow focus in the resources will provide consolidation for those students who need more time to work through learning material.

James Purser: A call out for People who science!

Tue, 2016-01-26 17:30

Right, there is just over two weeks to go until the inaugeral episode of Lunchtime Science and I am looking for People Who Science to interview for the show.

What I am looking to do is a ten minute segment where we introduce the Person Who Sciences and the project they are currently working on. We'll record it using Skype, either skype to skype or skype to phone, or in rare occasions, in real life.

So if you know anyone who's doing science and you think they would be worth talking to, please let me know. Ping me via the following:

  • @purserj on Twitter
  • James Purser on Facebook
  • james AT angrybeanie DOT com

Bring on the science :)

Blog Catagories: forscience! lunchtimescience podcasting

Dave Hall: Per Environment Config in Drupal 8

Mon, 2016-01-25 20:30

One of the biggest improvements in Drupal 8 is the new configuration management system. Config is now decoupled from code and the database. Unlike Drupal 6 and 7, developers no longer have to rely on the features module for moving configuration around.

Most large Drupal sites, and some smaller ones, require per environment configuration. Prior to Drupal 8 this was usually achieved using a combination of hard coding config variables and features. Drupal 8 still allows users to put config variables in the settings.php file, but putting config in code feels like a backward step given D8 emphasis on separating concerns.

For example we may have a custom module which calls a RESTful API of a backend service. There are dev, stage and production endpoints that we need to configure. We also keep our config out of docroot and use drush to import the config at deployment time. We have the following structure in our git repo:

/ +- .git/ | +- .gitignore | +- README.md | +- config/ | | | +- README.md | | | +- base/ | | | +- dev/ | | | +- prod/ | | | +- stage/ | +- docroot/ | +- scripts/ | +- and-so-on/

When a developer needs to export the config for the site they run drush config-export --destination=/path/to/project/config/base. This exports all of the configuration to the specified path. To override the API endpoint for the dev environment, the developer would make the config change and then export just that piece of configuration. That can be done by runing drush config-get mymodule.endpoint > /path/to/project/config/dev/mymodule.endpoint.yml.

Drupal 8 and drush don't allow you to import the 2 config sets at the same time, so we need to run 2 drush commands to import our config. drush config-import --partial --source=/path/to/project/config/base && drush config-import --partial --source=/path/to/project/config/dev. The first command imports the base config and the second applies any per environment overrides. The --partial flag prevents drush deleting any missing config. In most cases this is ok, but watch out if you delete a view or block placement.

Best practices are still emerging for managing configuration in Drupal 8. While I have this method working, I'm sure others have different approaches. Please leave a comment if you have an alternative method.

OpenSTEM: Introducing Aunt Madge’s Suitcase Activity

Mon, 2016-01-25 19:30

Oh no! Aunt Madge has gone off on her holiday around the world and left one of her suitcases behind!

She has sent a note to you to please bring her the suitcase, she has also sent a ticket so that you can fly after her to take her the suitcase.

School students need to help Aunt Madge by taking her suitcase to her. She has left a clue to where she is.

This Activity Resource consists of 3 PDFs with instructions, colour photos of locations around the world, a custom map for each location, and detailed descriptions.

Suitable for all school age year levels. We recommend using a globe in the classroom in addition to the OpenSTEM blackline world map so children get used to different projections. For home use, you can also use an atlas or other wall map, of course.

Also used in OpenSTEM’s Integrated History & Geography Program, this is a practical and fun activity to get kids relating to geography and learning about the world. There’s unlimited scope for building on, with (for instance) the child’s own friends and family members travelling or living overseas.

The Aunt Madge’s Suitcase Activity resource is available FREE for OpenSTEM Subscribers ($25+GST for non-subscribers). You can also download samples of some of our resources, to see and assess the quality of OpenSTEM materials for yourself before subscribing.

BlueHackers: Science on High IQ, Empathy and Social Anxiety | Feelguide.com

Sat, 2016-01-23 12:13

http://www.feelguide.com/2015/04/22/science-links-anxiety-to-high-iqs-sentinel-intelligence-social-anxiety-to-very-rare-psychic-gift/

Although Western medicine has radically transformed our world for the better, and given rise to some of the most remarkable breakthroughs in human history, in some ways it is still scratching at the lower slopes of the bigger picture. Only recently have our health systems begun to embrace the healing power of some ancient Eastern traditions such as meditation, for example. But overall, nowhere across the human health spectrum is Western medicine more unknowledgeable than in the realm of mental health. The human brain is the most complex biological machine in the known Universe, and our understanding of its inner workings is made all the more challenging when we factor in the symbiotic relationship of the mind-body connection.

When it comes to the wide range of diagnoses in the mental health spectrum, anxiety is the most common — affecting 40 million adults in the United States age 18 and older (18% of U.S. population). And although anxiety can manifest in extreme and sometimes crippling degrees of intensity, Western doctors are warming up to the understanding that a little bit of anxiety could be incredibly beneficial in the most unexpected ways. One research study out of Lakehead University discovered that people with anxiety scored higher on verbal intelligence tests. Another study conducted by the Interdisciplinary Center Herzliya in Israel found that people with anxiety were superior than other participants at maintaining laser-focus while overcoming a primary threat as they are being bombarded by numerous other smaller threats, thereby significantly increasing their chances of survival. The same research team also discovered that people with anxiety showed signs of “sentinel intelligence”, meaning they were able to detect real threats that were invisible to others (i.e. test participants with anxiety were able to detect the smell of smoke long before others in the group).

Another research study from the SUNY Downstate Medical Center in New York involved participants with generalized anxiety disorder (GAD). The findings revealed that people with severe cases of GAD had much higher IQ’s than those who had more mild cases. The theory is that “an anxious mind is a searching mind,” meaning children with GAD develop higher levels of cognitive ability and diligence because their minds are constantly examining ideas, information, and experiences from multiple angles simultaneously.

But perhaps most fascinating of all is a research study published by the National Institutes of Health and the National Center for Biotechnology Information involving participants with social anxiety disorder (i.e. social phobia). The researchers embarked on their study with the following thesis: “Individuals with social phobia (SP) show sensitivity and attentiveness to other people’s states of mind. Although cognitive processes in SP have been extensively studied, these individuals’ social cognition characteristics have never been examined before. We hypothesized that high-socially-anxious individuals (HSA) may exhibit elevated mentalizing and empathic abilities.” The research methods were as follows: “Empathy was assessed using self-rating scales in HSA individuals (n=21) and low-socially-anxious (LSA) individuals (n=22), based on their score on the Liebowitz social anxiety scale. A computerized task was used to assess the ability to judge first and second order affective vs. cognitive mental state attributions.”

Remarkably, the scientists found that a large portion of people with social anxiety disorder are gifted empaths — people whose right-brains are operating significantly above normal levels and are able to perceive the physical sensitivities, spiritual urges, motivations, and intentions of other people around them (see Dr. Jill Bolte Taylor’s TED Talk below for a powerful explanation of this ability). The team’s conclusion reads: “Results support the hypothesis that high-socially-anxious individuals demonstrate a unique profile of social-cognitive abilities with elevated cognitive empathy tendencies and high accuracy in affective mental state attributions.” To understand more about the traits of an empath you can CLICK HERE. And to see if you align with the 22 most common traits of an empath CLICK HERE.

Empaths who have fully embraced their abilities are able to function on a purely intuition-based level. As Steve Jobs once said, “[Intuition] is more powerful than intellect,” and in keeping with this appreciation, writer Carolyn Gregoire recently penned a fascinating feature entitled “10 Things Highly Intuitive People Do Differently” and you can read it in full by visiting HuffingtonPost.com. And to learn why Western medicine may be misinterpreting mental illness at large, be sure to read the fascinating account of Malidoma Patrice Somé, Ph.D. — a shaman and a Western-trained doctor. “In the shamanic view, mental illness signals the birth of a healer, explains Malidoma Patrice Somé. Thus, mental disorders are spiritual emergencies, spiritual crises, and need to be regarded as such to aid the healer in being born.” You can read the full story by reading “What A Shaman Sees In A Mental Hospital”. For more great stories about the human brain be sure to visit The Human Brain on FEELguide. (Sources: Business Insider, The Mind Unleashed, Huffington Post, photo courtesy of My Science Academy).

Lev Lafayette: Deleting "Stuck" Compute Jobs

Fri, 2016-01-22 15:30

Often on a cluster a user launches a compute job only to discover that they have some need to delete it (e.g., the data file is corrupt, there was an error in their application commands or PBS script). In TORQUE/PBSPro/OpenPBS etc this can be carried out by the standard PBS command, qdel.



[compute-login ~] qdel job_id

Sometimes however that simply doesn't work. An error message like the following is typical: "qdel: Server could not connect to MOM". I think I've seen this around a hundred times in the past few years.

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Chris Samuel: Mount Burnett Observatory Open Day – 23rd February 2016 – noon until late!

Thu, 2016-01-21 21:26

If you’re around Melbourne, interested in astronomy and fancy visiting a community powered astronomical observatory that has a very active outreach and amateur astronomy focus then can I interest you in the Mount Burnett Observatory open day this Saturday (January 23rd) from noon onwards?

We’re going to have all sorts of things going on – talks, telescopes, radio astronomy, tours of the observatory dome (originally built by Monash University), lots of enthusiastic volunteers!

We’re fundraising to build a new accessible modern dome to complement the existing facilities so please come and help us out.

This item originally posted here:



Mount Burnett Observatory Open Day – 23rd February 2016 – noon until late!

Russell Coker: Finding Storage Performance Problems

Thu, 2016-01-21 14:26

Here are some basic things to do when debugging storage performance problems on Linux. It’s deliberately not an advanced guide, I might write about more advanced things in a later post.

Disk Errors

When a hard drive is failing it often has to read sectors several times to get the right data, this can dramatically reduce performance. As most hard drives aren’t monitored properly (email or SMS alerts on errors) it’s quite common for the first notification about an impending failure to be user complaints about performance.

View your kernel message log with the dmesg command and look in /var/log/kern.log (or wherever your system is configured to store kernel logs) for messages about disk read errors, bus resetting, and anything else unusual related to the drives.

If you use an advanced filesystem like BTRFS or ZFS there are system commands to get filesystem information about errors. For BTRFS you can run “btrfs device stats MOUNTPOINT” and for ZFS you can run “zpool status“.

Most performance problems aren’t caused by failing drives, but it’s a good idea to eliminate that possibility before you continue your investigation.

One other thing to look out for is a RAID array where one disk is noticeably slower than the others. For example if you have a RAID-5 or RAID-6 array every drive should have almost the same number of reads and writes, if one disk in the array is at 99% performance capacity and the other disks are at 5% then it’s an indication of a failing disk. This can happen even if SMART etc don’t report errors.

Monitoring IO

The iostat program in the Debian sysstat package tells you how much IO is going to each disk. If you have physical hard drives sda, sdb, and sdc you could run the command “iostat -x 10 sda sdb sdc” to tell you how much IO is going to each disk over 10 second periods. You can choose various durations but I find that 10 seconds is long enough to give results that are useful.

By default iostat will give stats on all block devices including LVM volumes, but that usually gives too much data to analyse easily.

The most useful things that iostat tells you are the %util (the percentage utilisation – anything over 90% is a serious problem), the reads per second “r/s“, and the writes per second “w/s“.

The parameters to iostat for block devices can be hard drives, partitions, LVM volumes, encrypted devices, or any other type of block device. After you have discovered which block devices are nearing their maximum load you can discover which of the partitions, RAID arrays, or swap devices on that disk are causing the load in question.

The iotop program in Debian (package iotop) gives a display that’s similar to that of top but for disk io. It generally isn’t essential (you can run “ps ax|grep D” to get most of that information), but it is handy. It will tell you which programs are causing IO on a busy filesystem. This can be good when you have a busy system and don’t know why. It isn’t very useful if you have a system that is used for one task, EG a database server that is known to be busy doing database stuff.

It’s generally a good idea to have sysstat and iotop installed on all systems. If a system is experiencing severe performance problems you might not want to wait for new packages to be installed.

In Debian the sysstat package includes the sar utility which can give historical information on system load. One benefit of using sar for diagnosing performance problems is that it shows you the time of day that has the most load which is the easiest time to diagnose performance problems.

Swap Use

Swap use sometimes confuses people. In many cases swap use decreases overall disk use, this is the design of the Linux paging algorithms. So if you have a server that accesses a lot of data it might swap out some unused programs to make more space for cache.

When you have multiple virtual machines on one system sharing the same disks it can be difficult to determine the best allocation for RAM. If one VM has some applications allocating a lot of RAM but not using it much then it might be best to give it less RAM and force those applications into swap so that another VM can cache all the data it accesses a lot.

The important thing is not the amount of swap that is allocated but the amount of IO that goes to the swap partition. Any significant amount of disk IO going to a swap device is a serious problem that can be solved by adding more RAM.

Reads vs Writes

The ratio of reads to writes depends on the applications and the amount of RAM. Some applications can have most of their reads satisfied from cache. For example an ideal configuration of a mail server will have writes significantly outnumber reads (I’ve seen ratios of 5:1 for writes to reads on real mail servers). Ideally a mail server will cache all new mail for at least an hour and as the most prolific users check their mail more frequently than that most mail will be downloaded before it leaves the cache. If you have a mail server with reads outnumbering writes then it needs more RAM. RAM is cheap nowadays so if you don’t want to compete with Gmail it should be cheap to buy enough RAM to cache all recent mail.

The ratio of reads to writes is important because it’s one way of quickly determining if you have enough RAM and adding RAM is often the cheapest way of improving performance.

Unbalanced IO

One common performance problem on systems with multiple disks is having more load going to some disks than to others. This might not be a problem (EG having cron jobs run on disks that are under heavy load while the web server accesses data from lightly loaded disks). But you need to consider whether it’s desirable to have some disks under more load than others.

The simplest solution to this problem is to just have a single RAID array for all data storage. This is also the solution that gives you the maximum available disk space if you use RAID-5 or RAID-6.

A more complex option is to use some SSDs for things that require performance and disks for things that don’t. This can be done with the ZIL and L2ARC features of ZFS or by just creating a filesystem on SSD for the data that is most frequently accessed.

What Did I Miss?

I’m sure that I missed something, please let me know of any other basic things to do – or suggestions for a post on more advanced things.

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Craig Sanders: lm-sensors configs for Asus Sabertooth 990FX and M5A97 R2.0

Wed, 2016-01-20 23:26

I had to replace a motherboard and CPU a few days ago (bought an Asus M5A97 R2.0), and wanted to get lm-sensors working properly on it. Got it working eventually, which was harder than it should have been because the lm-sensors site is MIA, seems to have been rm -rf -ed.

For anyone else with this motherboard, the config is included below.

This inspired me to fix the config for my Asus Sabertooth 990FX motherboard. Also included below.

To install, copy-paste to a file under /etc/sensors.d/ and run sensors -s to make sensors evaluate all of the set statemnents.

# Asus M5A97 R2.0 # based on Asus M5A97 PRO from http://blog.felipe.lessa.nom.br/?p=93 chip "k10temp-pci-00c3" label temp1 "CPU Temp (rel)" chip "it8721-*" label in0 "+12V" label in1 "+5V" label in2 "Vcore" label in2 "+3.3V" ignore in4 ignore in5 ignore in6 ignore in7 ignore fan3 compute in0 @ * (515/120), @ / (515/120) compute in1 @ * (215/120), @ / (215/120) label temp1 "CPU Temp" label temp2 "M/B Temp" set temp1_min 30 set temp1_max 70 set temp2_min 30 set temp2_max 60 label fan1 "CPU Fan" label fan2 "Chassis Fan" label fan3 "Power Fan" ignore temp3 set in0_min 12 * 0.95 set in0_max 12 * 1.05 set in1_min 5 * 0.95 set in1_max 5 * 1.05 set in3_min 3.3 * 0.95 set in3_max 3.3 * 1.05 ignore intrusion0 #Asus Sabertooth 990FX # modified from the version at http://www.spinics.net/lists/lm-sensors/msg43352.html chip "it8721-isa-0290" # Temperatures label temp1 "CPU Temp" label temp2 "M/B Temp" label temp3 "VCORE-1" label temp4 "VCORE-2" label temp5 "Northbridge" # I put all these here as a reference since the label temp6 "DRAM" # Asus Thermal Radar tool on my Windows box displays label temp7 "USB3.0-1" # all of them. label temp8 "USB3.0-2" # lm-sensors ignores all but the CPU and M/B temps. label temp9 "PCIE-1" # If that is really what they are. label temp10 "PCIE-2" set temp1_min 0 set temp1_max 70 set temp2_min 0 set temp2_max 60 ignore temp3 # Fans label fan1 "CPU Fan" label fan2 "Chassis Fan 1" label fan3 "Chassis Fan 2" label fan4 "Chassis Fan 3" # label fan5 "Chassis Fan 4" # lm-sensor complains about this ignore fan2 ignore fan3 set fan1_min 600 set fan2_min 600 set fan3_min 600 # Voltages label in0 "+12V" label in1 "+5V" label in2 "Vcore" label in3 "+3.3V" label in5 "VDDA" compute in0 @ * (50/12), @ / (50/12) compute in1 @ * (205/120), @ / (205/120) set in0_min 12 * 0.95 set in0_max 12 * 1.05 set in1_min 5 * 0.95 set in1_max 5 * 1.05 set in2_min 0.80 set in2_max 1.6 set in3_min 3.20 set in3_max 3.6 set in5_min 2.2 set in5_max 2.8 ignore in4 ignore in6 ignore in7 ignore intrusion0 chip "k10temp-pci-00c3" label temp1 "CPU Temp"

lm-sensors configs for Asus Sabertooth 990FX and M5A97 R2.0 is a post from: Errata