Return-Path: Delivered-To: apmail-incubator-cassandra-user-archive@minotaur.apache.org Received: (qmail 49124 invoked from network); 14 Jul 2009 15:25:47 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 14 Jul 2009 15:25:47 -0000 Received: (qmail 94598 invoked by uid 500); 14 Jul 2009 15:25:56 -0000 Delivered-To: apmail-incubator-cassandra-user-archive@incubator.apache.org Received: (qmail 94587 invoked by uid 500); 14 Jul 2009 15:25:56 -0000 Mailing-List: contact cassandra-user-help@incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: cassandra-user@incubator.apache.org Delivered-To: mailing list cassandra-user@incubator.apache.org Received: (qmail 94578 invoked by uid 99); 14 Jul 2009 15:25:56 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 14 Jul 2009 15:25:56 +0000 X-ASF-Spam-Status: No, hits=1.2 required=10.0 tests=FS_REPLICA,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of jbellis@gmail.com designates 209.85.219.223 as permitted sender) Received: from [209.85.219.223] (HELO mail-ew0-f223.google.com) (209.85.219.223) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 14 Jul 2009 15:25:47 +0000 Received: by ewy23 with SMTP id 23so3093454ewy.12 for ; Tue, 14 Jul 2009 08:25:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=dELwgGBBdYKg9YpUXGzH3IYRja9Xr3sYkRivDv/p7bM=; b=g1LTm5ACiWnjNd7YJvv0CXm1A0V3AEmmnlqypFvRodcX7CL+YHhsOBbXCoKzaydo48 Z31HajcYONkzhgjDJEL+zhJwTN0IBTE5AMnMbIPp7J9A94uGVj1zPK7cvJk0IXeXP+4X CD34DxhMstMV5zbIF+/tyH4wWD4YKewKiMJvo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=LmTq0izsNJ516ViiQ+BxGSwrwb1Qgm8Jipj29XI326xgyz+v9Mq/uUxOaV1jWDx+n+ XepMx5hXBFUKQimkD1bOqI1GG0g7GIkWc2aD8Rw8kJAWV+moS3lnAlrtkP7I2+/EDsr/ 98opf56uAKZ1TEAzfAIl9MLC4wPZfpydFIJ9Y= MIME-Version: 1.0 Received: by 10.216.11.7 with SMTP id 7mr1766267wew.125.1247585126248; Tue, 14 Jul 2009 08:25:26 -0700 (PDT) In-Reply-To: References: Date: Tue, 14 Jul 2009 10:25:26 -0500 Message-ID: Subject: Re: replica on in the beginning or added later From: Jonathan Ellis To: cassandra-user@incubator.apache.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org Note that for N=2, quorum write is the same as block-for-all. That is why N=3 is more popular, because it allows for one node to be down but still give you a quorum for any key. -Jonathan On Tue, Jul 14, 2009 at 10:22 AM, wrote: > starting with replica count 2 is more prudent thanks > > On Tue, Jul 14, 2009 at 8:21 AM, Jonathan Ellis wrote: >> >> although the repair code Stu is working on >> (https://issues.apache.org/jira/browse/CASSANDRA-193) could handle >> increasing the replica count, IMO there's little sense in relying any >> more on features that don't yet exist than necessary. :) >> >> On Tue, Jul 14, 2009 at 10:17 AM, wrote: >> > as a followup question >> > the items we are storing are extremely valuable and we are using >> > cassandra >> > as a sql replacement tool.. ie no more postgres and all data from >> > cassandra, >> > given cassandra scalability >> > as we hit limits on postgres and found pgpool-II horizontal partitioning >> > too >> > clunky and skype, plproxy requires too much rewiring the client code. >> > should we start with a replica factor 1 and then increase replica factor >> > to >> > 2 >> > or is is prudent to start with a replica factor of 2 >> > Can cassandra replicate even after running for a long time with a >> > replica >> > factor of 1, if we change the replica factor to say 2 after 2months when >> > we >> > add more nodes and figure there is enough space now to replicate >> > thanks >> > >> > -- >> > Bidegg worlds best auction site >> > http://bidegg.com >> > > > > > -- > Bidegg worlds best auction site > http://bidegg.com >