cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Terje Marthinussen <tmarthinus...@gmail.com>
Subject Re: Re : get_range_slices result
Date Thu, 30 Jun 2011 15:35:20 GMT
It should of course be noted that how hard it is to load balance depends a
lot on your dataset....

Some datasets load balances reasonably well even when ordered and use of the
OPP is not a big problem at all (on the contrary) and in quite a few use
cases with current HW, read performance really isn't your problem in any
case.

You may for instance find it more useful to simplify adding nodes for
growing data capacity to the "end" of the token range using OPP than getting
extra performance you don't really need.

Terje

On Fri, Jun 24, 2011 at 7:16 PM, Sylvain Lebresne <sylvain@datastax.com>wrote:

> On Fri, Jun 24, 2011 at 10:21 AM, karim abbouh <karim_rbt@yahoo.fr> wrote:
> > i want get_range_slices() function returns records sorted(orded)  by the
> > key(rowId) used during the insertion.
> > is it possible?
>
> You will have to use the OrderPreservingPartitioner. This is no
> without inconvenience however.
> See for instance
> http://wiki.apache.org/cassandra/StorageConfiguration#line-100 or
>
> http://ria101.wordpress.com/2010/02/22/cassandra-randompartitioner-vs-orderpreservingpartitioner/
> that give more details on the pros and cons (the short version being
> that the main advantage of
> OrderPreservingPartitioner is what you're asking for, but it's main
> drawback is that load-balancing
> the cluster will likely be very very hard).
>
> In general the advice is to stick with RandomPartitioner and design a
> data model that avoids needing
> range slices (or at least needing that the result is sorted). This is
> very often not too hard and more
> efficient, and much more simpler than to deal with the load balancing
> problems of OrderPreservingPartitioner.
>
> --
> Sylvain
>
> >
> > ________________________________
> > De : aaron morton <aaron@thelastpickle.com>
> > À : user@cassandra.apache.org
> > Envoyé le : Jeudi 23 Juin 2011 20h30
> > Objet : Re: get_range_slices result
> >
> > Not sure what your question is.
> > Does this help ? http://wiki.apache.org/cassandra/FAQ#range_rp
> > Cheers
> > -----------------
> > Aaron Morton
> > Freelance Cassandra Developer
> > @aaronmorton
> > http://www.thelastpickle.com
> > On 23 Jun 2011, at 21:59, karim abbouh wrote:
> >
> > how can get_range_slices() function returns sorting key ?
> > BR
> >
> >
> >
> >
>

Mime
View raw message