Re: Solr and vnodes anyone?

[Eric Stevens]

IIRC in DSE 4.6 using vnodes is basically always a bad idea in your Solr
datacenter.  The overhead was more than you could reasonably want to pay
unless your vnode count was low enough that you lost all the advantage.

Around 4.7 there were significant performance improvements for vnodes in
DSE Solr.  In that era we experimented with several vnode counts, and 64
was where we settled as the best tradeoff between performance degradation
(increase in fanouts in the read path) and cluster management.

I believe there were even more improvements in 4.8, but we have not re-run
our earlier experiments; we're still running at scale with 64 vnodes.

On Mon, Mar 28, 2016 at 8:59 PM Jack Krupansky 
wrote:

> Somebody recently asked me for advice on the use of Solr (DSE Search) and
> vnodes, so I was wondering... is anybody here actually using Solr/DSE
> Search with vnodes enabled? If so, with what token count? The default of
> 256 would result in somewhat suboptimal query performance, so the question
> is whether 64 or even 32 would deliver acceptable query performance?
> Anybody here have any practical experience on this issue, either testing or
> even better, in production?
>
> Absent any further input, my advice would be to limit DSE Search/Solr to a
> token count of 64 per node.
>
> -- Jack Krupansky
>

Solr and vnodes anyone?

[Jack Krupansky]

Somebody recently asked me for advice on the use of Solr (DSE Search) and
vnodes, so I was wondering... is anybody here actually using Solr/DSE
Search with vnodes enabled? If so, with what token count? The default of
256 would result in somewhat suboptimal query performance, so the question
is whether 64 or even 32 would deliver acceptable query performance?
Anybody here have any practical experience on this issue, either testing or
even better, in production?

Absent any further input, my advice would be to limit DSE Search/Solr to a
token count of 64 per node.

-- Jack Krupansky