In G1 large objects are always allocated in the old generation, requiring a complete heap liveness analysis (full gc, marking) to reclaim them.
This is far from ideal for many transaction based enterprise applications that create large objects that are only live until a (typically short-lived) transaction is not completed (e.g. in a ResultSet of a JDBC query that generates a large result).
This results in the heap filling up relatively quickly, typically leading to unnecessary marking cycles just to reclaim them.
Investigate options to reclaim these objects more quickly; options found so far are:
a) logically keep LOBs in young gen, doing in-place aging
b) keep LOBs in the old gen, but use the remembered set and information from young collection to determine LOB liveness