30% overhead is pretty brutal. I think this is basic support for it, and not necessarily a recommendation to use it.
From http://www.datastax.com/documentation/datastax_enterprise/4.6/datastax_enterprise/ana/anaNdeOps.html?scroll=anaNdeOps__implicationsVnodes *DataStax does not recommend turning on vnodes *for other Hadoop use cases *or for Solr nodes*, but you can use vnodes for any Cassandra-only cluster, or a Cassandra-only data center in a mixed Hadoop/Solr/Cassandra deployment. If you have enabled virtual nodes on Hadoop nodes, disable virtual nodes before using the cluster. On Mon, Feb 23, 2015 at 9:34 AM, Jack Krupansky <jack.krupan...@gmail.com> wrote: > DSE 4.6 improved Solr vnode performance dramatically, so that vnodes for > Search workloads is now no longer officially discouraged. As per the > official doc for improvements, : "*Ability to use virtual nodes (vnodes) > in Solr nodes. Recommended range: 64 to 256 (overhead increases by > approximately 30%)*". A vnode token count of 64 or 32 would reduce that > overhead further. And... the new 4.6 feature of being able to direct a Solr > query to a specific partition essentially eliminates that overhead entirely. > > -- Jack Krupansky > > On Mon, Feb 23, 2015 at 11:23 AM, Eric Stevens <migh...@gmail.com> wrote: > >> Vnodes is officially disrecommended for DSE Solr integration (though a >> small number isn't ruinous). That might be why they still don't enable them >> by default. >> On Feb 21, 2015 3:58 PM, "mck" <m...@apache.org> wrote: >> >>> At least the problem of hadoop and vnodes described in CASSANDRA-6091 >>> doesn't apply to spark. >>> (Spark already allows multiple token ranges per split). >>> >>> If this is the reason why DSE hasn't enabled vnodes then fingers crossed >>> that'll change soon. >>> >>> >>> > Some of the DataStax videos that I watched discussed how the Cassandra >>> Spark connecter has >>> > optimizations to deal with vnodes. >>> >>> >>> Are these videos public? if so got any link to them? >>> >>> ~mck >>> >> >
