> > I have a patch for trunk which I just have to get time to test a bit before I submit. > It is for super columns and will use the super columns timestamp as the base and only store variant encoded offsets in the underlying columns. >
Could you please measure how much real benefit it brings (in real RAM consumption by JVM). It is hard to tell will it give noticeable results or not. AFAIK memory structures used for memtable consume much more memory. And 64-bit JVM allocates memory aligned to 64-bit word boundary. So 37% of memory consumption reduction looks doubtful.
