28 January 2017

28th of January

Its still hot here in Sydney. We've had a few cool days where I have managed to run some Einstein or Seti work. The Einstein CPU tasks take about 16 hours so I am tending to run Seti as they're somewhere between 1 and 3 hours depending on the work unit.

I purchased another 5 port USB charger which I am using to power four Raspberry Pi2's. Its an Astrotek brand with a part number of AT-UPS-008B. Provided you only use 4 out of the 5 ports its fine. I have another one running four of the Pi3's. It might actually be able to run five (it reduces power output to each port when you plug in a 5th device) but I haven't tried five.

17 January 2017

17th of January

Its summer here in Sydney and its hot. Today was 32 degrees (C). The only things running on the farm are the Raspberry Pi's.

I got another 5 port USB charger. The ones I'm using to run the Pis are an Astrotek brand. Its a 5 port 8 amp unit. If you only plug 4 devices into it it can provide 2 amps per port. If you plug a 5th one in it drops the available power so I normally run four. The second charger is running the four Pi2's that have been sitting around gathering dust. I get a RAC (recent average credit) on Einstein BRP4 of about 300 from a Pi2's and 515 from a Pi3.

There are some rumours of a Pi4. There is nothing official at the moment but historically the Raspberry Pi foundation announce new models in February. The suggestion is it will have an ARM Cortex A53 processor at 1.8Ghz and 2Gb of memory. There are contrary suggestions that there won't be a new one for a few years as the foundation ordered 600,000 Pi3's and would need to sell these first.

31 December 2016

New Years Eve 2016

My last post for 2016.

Its hot here in Sydney so everything is off apart from the Raspberry Pi's that don't seem to mind the hot weather. I need to find somewhere else to put the computers. Somewhere air conditioned.

To recap this year, the farm has grown a bit in size and therefore the compute capability. I have a lot of old hardware to sell off to make some room and fund future upgrades. The farm at the end of this year consists of:
2 x i7-5820k (6 core/12 thread) machines with a GTX1060 each
8 x i7-6700 (4 core/8 thread) machines
2 x i3-6100T with a GTX970 each
9 x Raspberry Pi3's

I am also looking at moving away from Windows due to on-going issues with windows update and Microsoft's insistence in maintaining my computers for me.  I will probably move the Intel GPU part of the farm across to Linux initially.

I also want to get the Alphaserver going. I have had it running before but got caught by the hobbyist license running out each year. I have renewed it twice. There is a move to port OpenVMS onto the x86 architecture that could offer another alternative to Windows.

Next years "to do" list:
1. Get air conditioned location for computers
2. Sell off old hardware
3. Move away from Windows
4. Probable multi-core CPU upgrades (Ryzen)
5. Probable networking upgrades
6. Get BOINC-MPI going
7. Get AlphaServer going
8. More GPU upgrades

As you can see quite a few things to get done next year. All the best for 2017.

23 December 2016

Add jessie-backports repository for Rpi

The Raspberry Pi running Raspbian is as I write this on the Jessie release. This is what is known as a long-term release so while there will be some security and bug fixes no new versions of software are added. If you want to get later versions of software you can compile your own, use a testing/unstable release or add the jessie-backports repository.

Unfortunately the Raspberry Pi foundation don't have a jessie-backports repository. Debian however maintain one. Debian support the ARMv7 and later so this will work for the Raspberry Pi2 and Pi3. Don't use this on the Pi Zero, B+ or older (ARMv6) Raspberry Pi.

I use the command line for accessing my Pi's so these commands are done in a terminal window.


Add to sources.list
The first step is to add the jessie-backports to our sources.list file so that apt can include it. To do this we need to edit the file and add an extra entry. Type following commands:

cd /etc/apt
sudo nano sources.list

We need to add the following line after the Jessie entry
deb http://httpredir.debian.org/debian jessie-backports main contrib non-free

Save the file by doing Ctrl-O and when prompted for the filename press the Enter key. To exit do a Ctrl-X. That is hold the Control key down and press the letter.

The httpredir entry is a special entry that tells it to get the files from the fastest available Debian mirror. The jessie-backports part tells it which release.


Add gpg keys
Now we've added jessie-backports we need to get the latest list of program versions. Type the following command:

sudo apt-get update

This will give 2 error messages about missing gpg keys. We'll need to add them with the following commands. Check the keys given in the error message match the ones below and if not replace the key values with the ones from the error message.

gpg --keyserver pgpkeys.mit.edu --recv-key  8B48AD6246925553     
gpg -a --export 8B48AD6246925553 | sudo apt-key add -
gpg --keyserver pgpkeys.mit.edu --recv-key  7638D0442B90D010     
gpg -a --export 7638D0442B90D010 | sudo apt-key add -

Don't forget the hyphen on the end of the apt-key add lines. Now lets try that again.

sudo apt-get update

Which should work this time and will check more repositories. I have received some errors where apt is unable to get the files but retrying the command a few minutes later works fine.

To tell apt we want a version from the jessie-backports repository we need to include -t jessie-backports to the install command, otherwise it simply picks the version from the jessie repository. For example:

sudo apt-get install –t jessie-backports boinc-client

This tells apt we want to install the boinc-client package from jessie-backports.