Gojko Adzic reports [1] on Twitter developer Evan Weavers presentation [2],"Improving Running Components", at QCon London 2009 [3] in March. In his talk Evan Weaver covers the strategy they adopted to radically improve performance and scaling whilest at the same time maintaining 100% availability of the service. There are facinating statistics on the Twitter loads, their strategy and mention of the important part Scala played in this challenging upgrade. See the report here [1] and the slides here [2]
Links:
[1] http://gojko.net/2009/03/16/qcon-london-2009-upgrading-twitter-without-service-disruptions/
[2] http://blog.evanweaver.com/articles/2009/03/13/qcon-presentation/
[3] http://qconlondon.com/london-2009/