Bullshit
" A typical Java heap size is on the order of 2GB, with sometimes 4GB or 6GB sizes; beyond that and Java's memory management starts to thrash."
Is this a sponsored story? This is pure weapons grade balonium. First post I could find here, it's old and they happily settled on a 100Gb heap on a large server ->
http://troyjsd.blogspot.co.uk/2009/05/holy-shit-100gb-heap-50-new-gen-less.html
Very old JVMs where heap fragmentation was an issue and this would be true (untuned) - I'd guess pretty much any modern JVM and this is simply untrue.