Hi, This is arena allocation of memtables. See here for more infos : http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-performance
De : graham sanderson <gra...@vast.com> A : dev@cassandra.apache.org, Date : 16/05/2014 14:03 Objet : Things that are about 1M big So just throwing this out there for those for whom this might ring a bell. I?m debugging some CMS memory fragmentation issues on 2.0.5 - and interestingly enough most of the objects giving us promotion failures are of size 131074 (dwords) - GC logging obviously doesn?t say what those are, but I?d wager money they are either 1M big byte arrays, or less likely 256k entry object arrays backing large maps So not strictly critical to solving my problem, but I was wondering if anyone can think of any heap allocated C* objects which are (with no significant changes to standard cassandra config) allocated in 1M chunks. (It would save me scouring the code, or a 9 gig heap dump if I need to figure it out!) Thanks, Graham
