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From Avinash Lakshman <avinash.laksh...@gmail.com>
Subject Re: Memtable size and garbage collection in JVM
Date Fri, 05 Mar 2010 04:53:59 GMT
Also huge memtables will increase your recovery time. Which may not be
something you want.

Avinash

On Thu, Mar 4, 2010 at 8:50 PM, Jonathan Ellis <jbellis@gmail.com> wrote:

> 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.)
>
> -Jonathan
>
> On Thu, Mar 4, 2010 at 9:44 PM, Bill Au <bill.w.au@gmail.com> 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?
> > Bill
> >
> >
>

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