On Wed, Feb 16, 2011 at 11:22 AM, Victor Kabdebon <victor.kabde...@gmail.com> wrote: > Thanks robert, and do you know if there is a way to control the maximum > likely number of memtables ? (I'd like to cap it at 2)
That "likely number of memtables" is the number of memtables which : a) have been created b) may or may not have hit a flush threshold c) have not been flushed d) and therefore are resident in memory The only way to keep the number of resident memtables at or around 2 is to never write to your node significantly faster than you can flush. Given other consumers of system I/O like compaction and the implications of multiple CFs which all contend to flush, this can be non-trivial in practice. "3" in my calculation here is a "safety ceiling" type value, in that you would really have to be pushing your node or have a small number of high-write CFs to actually have 3 memtables per CF resident across all CFs on a node. =Rob