With a little delay, right on a first week of December why not to share 2 speeches that our guys had during RubyShift 2012
conference. Here you go!
Deadsimple JRuby troubleshooting by Sergey Boiko. RubyShift 2012
And a presentation:
PostgreSQL in Highload Projects by Alexey Vasiliev. RubyShift 2012
And a nice visualisation: