Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 6393 invoked from network); 6 Aug 2010 21:15:26 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 6 Aug 2010 21:15:26 -0000 Received: (qmail 7539 invoked by uid 500); 6 Aug 2010 21:15:24 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 7490 invoked by uid 500); 6 Aug 2010 21:15:24 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 7482 invoked by uid 99); 6 Aug 2010 21:15:24 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 06 Aug 2010 21:15:24 +0000 X-ASF-Spam-Status: No, hits=4.3 required=10.0 tests=FS_REPLICA,RCVD_IN_DNSWL_NONE,SPF_NEUTRAL X-Spam-Check-By: apache.org Received-SPF: neutral (nike.apache.org: local policy) Received: from [74.125.82.44] (HELO mail-ww0-f44.google.com) (74.125.82.44) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 06 Aug 2010 21:15:18 +0000 Received: by wwj40 with SMTP id 40so11221136wwj.25 for ; Fri, 06 Aug 2010 14:14:57 -0700 (PDT) MIME-Version: 1.0 Received: by 10.216.45.6 with SMTP id o6mr1328829web.74.1281129297875; Fri, 06 Aug 2010 14:14:57 -0700 (PDT) Received: by 10.216.234.219 with HTTP; Fri, 6 Aug 2010 14:14:57 -0700 (PDT) In-Reply-To: References: <288143.1574.qm@web65705.mail.ac4.yahoo.com> <261267.8094.qm@web65707.mail.ac4.yahoo.com> <340977.98034.qm@web65704.mail.ac4.yahoo.com> <710037.14824.qm@web65712.mail.ac4.yahoo.com> Date: Fri, 6 Aug 2010 14:14:57 -0700 Message-ID: Subject: Re: set ReplicationFactor and Token at Column Family/SuperColumn level. From: Benjamin Black To: user@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Virus-Checked: Checked by ClamAV on apache.org "Additional keyspaces have very little overhead (unlike CFs)." On Fri, Aug 6, 2010 at 9:42 AM, Zhong Li wrote: > > If I create 3-4 keyspaces, will this impact performance and resources (es= p. > memory and disk I/O) too much? > > Thanks, > > Zhong > > On Aug 5, 2010, at 4:52 PM, Benjamin Black wrote: > >> On Thu, Aug 5, 2010 at 12:59 PM, Zhong Li wrote: >>> >>> The big thing bother me is initial ring token. We have some Column >>> Families. >>> It is very hard to choose one token suitable for all CFs. Also some >>> Column >>> Families need higher Consistent Level and some don't. If we set >> >> Consistency Level is set by clients, per request. =A0If you require >> different _Replication Factors_ for different CFs, then just put them >> in different keyspaces. =A0Additional keyspaces have very little >> overhead (unlike CFs). >> >>> ReplicationFactor too high, it is too costy for crossing datacenter, >>> especially in otherside the world. >>> >>> I know we can setup multiple rings, but it costs more hardware. >>> >>> if Cassandra can implement =A0Ring,Token and RF on the CF level, or eve= n >>> SuperColumn level, it will make design much easier and more efficiency. >>> >>> Is it possible? >>> >> >> The approach I described above is what you can do. =A0The rest of what >> you asked is not happening. >> >> >> >> b > >