Also huge memtables will increase your recovery time. Which may not be something you want.
A lot of churn is hard on Cassandra because of
http://wiki.apache.org/cassandra/DistributedDeletes, but Cassandra is
so fast that it may make up for that depending on your needs.
It's not designed to eliminate i/o entirely, no. But if you set
RowsCached=100% in 0.6 you'll get something pretty close to that.
(That is a better approach than huge Memtables.)
On Thu, Mar 4, 2010 at 9:44 PM, Bill Au <firstname.lastname@example.org> wrote:
> I am running on a machine with 16 GB of memory. I am thinking that the
> bigger MemtableSizeIbMB, the more data will be kept in memory so there will
> be less disk I/O. Can I eliminate disk I/O all together if all my data fits
> inside Memtable? My application is constantly inserting new data and remove
> old ones. Will keeping everything in Memtable generate so much garbage
> collection activity that it would impact performance?