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ATLAS@Home native app on Ubuntu Bionic


In case you haven't heard: the ATLAS@Home app is available for download in Linux. This app normally runs inside a Virtualbox VM, which is a good way to get things working with different operating systems, but adds the overhead of a virtual machine. This can be avoided when ATLAS@Home is running on your Ubuntu Bionic computer by following the steps outlined below.

First, let's make sure you have the essentials:

sudo apt update && sudo apt -y dist-upgrade
sudo apt install attr autofs curl boinc-client fuse gawk gdb lsb-release perl psmisc python2.7 singularity-container uuid-dev uuid wget

Next step is to add the repositories and install cvmfs.

wget https://ecsft.cern.ch/dist/cvmfs/cvmfs-release/cvmfs-release-latest_all.deb \
http://cvmrepo.web.cern.ch/cvmrepo/apt/pool/bionic-testing/main/cvmfs-config-default_1.4-1_all.deb \
http://cvmrepo.web.cern.ch/cvmrepo/apt/pool/bionic-testing/main/cvmfs_2.5.1~1+ubuntu18.04_amd64.deb
sudo dpkg -i cvmfs*.deb

Before you continue, however, you may have noticed the following warning:

Warning: this distribution is not supported. Using Ubuntu 12.04 packages as fallback.
If you don't get this: excellent! If you do: it simply means that the repository hasn't been correctly configured for Bionic yet. The fix is simple enough:

sudo sed -i 's/precise/bionic/g' /etc/apt/sources.list.d/cernvm.list
Note that an update to the cvmfs-release package may overwrite these changes, so you'll have to do it again.
Also note that, at time of writing, the Bionic repos have not been set up correctly, which is why you need to manually download the packages. If the packages change (usually due to a version update), you can find the required packages at http://cvmrepo.web.cern.ch/cvmrepo/apt/pool/bionic-testing/main/. Once the repositories are set up properly, the packages will update as expected.

And now a few more steps:

sudo cvmfs_config setup
printf "CVMFS_REPOSITORIES=atlas.cern.ch,atlas-condb.cern.ch,grid.cern.ch\nCVMFS_HTTP_PROXY=DIRECT\n" | sudo tee /etc/cvmfs/default.local
sudo systemctl restart autofs

Finally, check everything is okie dokie:

$ cvmfs_config probe
Probing /cvmfs/atlas.cern.ch... OK
Probing /cvmfs/atlas-condb.cern.ch... OK
Probing /cvmfs/grid.cern.ch... OK

Cushty.

Notes:
  • If you have a proxy, you should use that in place of CVMFS_HTTP_PROXY=DIRECT. However, this must be set to something or it will fail.
  • If you have a lot of machines and a server which runs all the time (such as a proxy server), you will probably be better off installing cvmfs on the server, and exporting the share over NFS. This will save a lot of duplication and inbound bandwidth.
  • At time of writing, none of the LHC@Home applications run on GPU for mainly historical reasons. Given improvements in the way VMs are handled this may change in the future. If you wish to use your GPU then you will also need to install the relevant drivers and libraries.
References:
  1. https://cernvm.cern.ch/portal/filesystem/quickstart
  2. https://lhcathomedev.cern.ch/lhcathome-dev/forum_thread.php?id=348
  3. http://cvmrepo.web.cern.ch/cvmrepo/apt/pool/
  4. https://twiki.cern.ch/twiki/bin/view/CvmFS/ClientSetupCERN

The Ghost in the Machine

A great number of years ago a CRT monitor I was using gave up. It had served its master well for many years. My father (yes I was still a child!), just out of interest, rang the company he bought the original equipment from. To our surprise they sent us a replacement LCD screen. It works just as well as the original CRT and had the same sort of specs so we were more than happy with the result.

The monitor itself has no identifying marks other than a model number: M15EWA. A Google search suggests two brand names but neither may be the original manufacturer.

I discovered that using a very simple procedure I can get a rather unusual effect from the monitor.



The monitor presents to me its evil eye. If you are a little worse for wear and sat in the dark when this happens, then staring into the eye is quite an experience.

The answer of course is that the monitor is possessed by a dæmon intent on bringing destruction to the world. First by making me switch the monitor on and off. Oh, the seconds I have wasted doing this! It could even be a full minute by now.

Other options are that this is either and Easter egg, albeit an unusual one, or a firmware issue. It is far from being a major issue but I did find it interesting.

To trigger this behaviour:
  1. Switch off the monitor.
  2. Allow the computer to put the graphics card to sleep.
  3. Simultaneously switch the monitor back on and wake the computer.
It looks as if waking the computer during the monitor's POST gets it a little confused, and makes it do pretty things. The same thing occurs on any computer I test it on. Or it's a djinn.

Raspberry Pi 3 on sale now

RASPBERRY PI 3 ON SALE NOW AT $35

In celebration of our fourth birthday, we thought it would be fun to release something new. Accordingly, Raspberry Pi 3 is now on sale for $35 (the same price as the existing Raspberry Pi 2), featuring:

  • A 1.2GHz 64-bit quad-core ARM Cortex-A53 CPU (~10x the performance of Raspberry Pi 1)
  • Integrated 802.11n wireless LAN and Bluetooth 4.1
  • Complete compatibility with Raspberry Pi 1 and 2
Raspberry Pi 3 Model B
Raspberry Pi 3 Model B

BCM2837, BCM43438 AND RASPBERRY PI 3

For Raspberry Pi 3, Broadcom have supported us with a new SoC, BCM2837. This retains the same basic architecture as its predecessors BCM2835 and BCM2836, so all those projects and tutorials which rely on the precise details of the Raspberry Pi hardware will continue to work. The 900MHz 32-bit quad-core ARM Cortex-A7 CPU complex has been replaced by a custom-hardened 1.2GHz 64-bit quad-core ARM Cortex-A53. Combining a 33% increase in clock speed with various architectural enhancements, this provides a 50-60% increase in performance in 32-bit mode versus Raspberry Pi 2, or roughly a factor of ten over the original Raspberry Pi.

James Adams spent the second half of 2015 designing a series of prototypes, incorporating BCM2837 alongside the BCM43438 wireless “combo” chip. He was able to fit the wireless functionality into very nearly the same form-factor as the Raspberry Pi 1 Model B+ and Raspberry Pi 2 Model B; the only change is to the position of the LEDs, which have moved to the other side of the SD card socket to make room for the antenna. Roger Thornton ran the extensive (and expensive) wireless conformance campaign, allowing us to launch in almost all countries simultaneously. Phil Elwell developed the wireless LAN and Bluetooth software.

All of the connectors are in the same place and have the same functionality, and the board can still be run from a 5V micro-USB power adapter. This time round, we’re recommending a 2.5A adapter if you want to connect power-hungry USB devices to the Raspberry Pi.

You’ll need a recent NOOBS or Raspbian image from our downloads page. At launch, we are using the same 32-bit Raspbian userland that we use on other Raspberry Pi devices; over the next few months we will investigate whether there is value in moving to 64-bit mode.

Find a Raspberry Pi 3:

Blogger Template Designer does not apply web font selections

The Blogger Template Designer offers a quick and easy way to (re-)design your blog without having to faff around with the template code.

Blogger Template Designer

...except that it doesn't work properly.

Header is not using the selected font

Why?

Well, it would appear that when you open the BTD it nicely downloads all the web fonts so that you can preview them easily. The problem is that once you have made your selection the only part of the template code that is changed is the font name. There is nothing to instruct the browser that it needs to download the font in order to render it. Sadly, you will have to faff around with the template code.

The first thing to do is to find the font you wanted over at Google Fonts. In my case it is Gruppo: https://www.google.com/fonts/specimen/Gruppo. There should be a link that takes you into Google Fonts where you can play around with the fonts of your choice, and the styles of your choice. The buttons along the bottom will take you to a page that shows you what code you need to add to your page. In my case this was:

<link href='https://fonts.googleapis.com/css?family=Gruppo' rel='stylesheet' type='text/css' />

And now your selection should work. The BTD should have inserted enough into the template at this point to allow the browser to render your font correctly. If not... 😕.

Note: Things may not work nicely in Internet Explorer. That's tough luck - don't use Internet Explorer.
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