Here's a nice preliminary number with the FST, 50 million dates of the form yyyyMMddHHmmssSSS, with each incremented by one millisecond. The FST is 984 bytes, with an incrementing long to point to the presumably MMap'd value data. This's a bit crazy.
Perhaps we should try other increments as well? Given that HBase keys especially are probably close increments of each other, I think the FST can always be loaded into RAM with pointers out to the actual values.
