Open bioLab Graz Austria – Offenes Labortreffen 28.02.2016

Buntes Treiben und nein, es ist nicht Faschingsdienstag im OLGA.

Nicht nur, dass wieder viele Leute uns die Ehre erteilt haben uns am Anfang des Semesters zu besuchen und sich das Open bioLab Graz Austria anzusehen, auch wenn aufgrund von Umbau-Arbeiten wenig Platz vorhanden war.

Für diesem Zweck haben wir Serratia und Pseudomonas- Kulturen aus dem Kühlschrank geholt und damit LB Medium beimpft, die ONC haben sich nice verfärbt.

ONC

 

Aus den Kulturen wurden dann Glycerol-Stocks hergestellt und bei -20°C gelagert, für Arbeiten im kommenden Semester. Die anderen Stämme vom OLGA werden dem selben Vorgang unterzogen.

Was für wissenschaftliche Arbeiten stets voraus gestellt wird und dem nichts-ahnendem Forscher immer ein Ärgernis erspart sind Kontrollen. Hier sind vier unterschiedliche Kulturen auf MacConkey-Agar ausgestrichen worden:

MacConkey

 

Links oben: E. coli K12          Rechts oben: Pseudomonas sp.
Links unten: E. coli XL1        Rechts unten: Serratia marcescens

Bis auf eine sind sämtliche Kulturen in Ordnung, nur E. coli XL1 muss erneut begutachtet werden bevor die Glyc-Stocks erstellt werden. Die Platten, von denen Bakterien zum Inokulieren entnommen wurden, sind immerhin den ganzen Februar ungeachtet im Kühlschrank gelegen.

Im Labor ist es derzeit etwas eng und chaotisch, da wir noch dabei sind die Lüftungsanlage fertig zusammen zu bauen, aber hilfsbereite Arbeitskräfte sind stets gern gesehen ;)

Python Usergroup @ realraum

On February 1 there was once again the monthly Python Usergroup Graz meeting.
This time it didn’t take place at the Spektral, though, as at the
last second (well, a week in advance…) a schedule collision happened and the
nice folks behind spektral had to use that room for themselves. Luckily,
within a couple of hours a new venue for that evening was found at the
Realraum! Big thanks to Michael and everyone else who helped here!

So, what happened? We had two talks! Horst gave a short tour through some of
nice string-formatting mechanisms you have with Python, something he had already
written about here a couple of weeks ago. If you want to learn more, simply
read that post and visit pyformat.info, which contains many more examples 😉

Right after that, we had a quick introduction into some of the awesome things
you can do with Pandas. Big thanks to Moritz for that 😊 You can find his
slides on our mailinglist.

We also had three visitors from the Vienna Python usergroup who come by
every once in a while and who have their next meetup incl. a coding dojo
on February 17 at the Metalab 😊

The next meetup in Graz will be on March 1 most likely again at the
Spektral. Official announcement will be made soonish on Meetup.com,
our website and all the other nice places you can find us 😃

Report on membershipmeeting Feb2016

This months membership meetup was more cozy than usual. Also a lot more productive, judging on what happened the days after ;-)

The highlights:

  • Easterhegg 2016. Originally we wanted to help out with cool lighting and take part as a big realraum delegation from Graz. Unfortunately tickets were quite suddenly and unexpectadly sold out. So there will be no realraum @ Easterhegg 2016 Salzburg. Too bad. Very sad. Some of us are going to Revision16 instead though.
  • Lasercutter exhaustvent and OLGA vents. Is finally going to be built. See upcoming post with pictures.
  • Curtain: Will finally happen. New curtain rod installation was finished on Wednsday and Curtain is scheduled for hanging on Friday.
  • mur.at: The future of our internet uplink is in flux. Interessting stuff will happen 2016/2017.
  • Finances: Over the next months we will test and then maybe introduce a new formal system for financing stuff in realraum.

Light in realraum is now faster

licht.realraum.at, went FTLw today. That is… it became much Faster Than Last week. :-)

Since the Raspbian image upgrade and move to a bigger (but slower) SDcard, licht.realraum.at had become truly sluggish. To the point that pressing a button to turn on the light or change the stereo volume could take up to 6 seconds until something happened. (Obviously we disabled the swap-file long ago.)

The problem was quickly identified. Processes don’t load quickly enough.
The fact that the whole systems was a dunghill of bashscript cgi-scripts and python helper scripts also did not help. At all.

First attempt to rectify this: rewrite the python helper rf433ctl.py. Formerly it was a simple script that would be called by the cgi-script and send the appropriate bytes down to the teensy.
Each call to it, however now took forever. So. I rewrote it as a daemon that would constantly stay in memory and be nudged by other instances of it via RPC. The idea being, if it’s already completely in memory, loading a second instance should be faster. Right? Wrong!. Unfortunately that did not work out at all.

Second attempt to rectify this: Remove the kiosk functionality and thus memory-hog midori from licht. Thankfully a very nice person gifted us a RaspberryPi per (almost) anonymous letter, so we had the necessary hardware on-hand to split the functionality onto two separate boxes: licht.realraum.at and smallkiosk.realraum.at
Unfortunately, even freeing up 60% of memory did not even put a dent into the problem.

So.. third and last attempt. Hit it with go ;-> In a 3 hour session, I rewrote the whole dunghill as a monolithic golang daemon/webserver/tty-handler which, once loaded, always stays in memory. Then I got rid of lighthttpd and the python scripts. Result… Speedup from 6s to <=0.05s !! Should have done this right away really…