From user-return-26790-apmail-cassandra-user-archive=cassandra.apache.org@cassandra.apache.org Thu Jun 7 09:41:55 2012 Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 21B32C8BA for ; Thu, 7 Jun 2012 09:41:55 +0000 (UTC) Received: (qmail 96585 invoked by uid 500); 7 Jun 2012 09:41:52 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 96562 invoked by uid 500); 7 Jun 2012 09:41:52 -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 96553 invoked by uid 99); 7 Jun 2012 09:41:52 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Jun 2012 09:41:52 +0000 X-ASF-Spam-Status: No, hits=2.2 required=5.0 tests=FSL_RCVD_USER,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a91.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Jun 2012 09:41:46 +0000 Received: from homiemail-a91.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a91.g.dreamhost.com (Postfix) with ESMTP id 31888AE079 for ; Thu, 7 Jun 2012 02:41:23 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; q=dns; s=thelastpickle.com; b=lDlbAsdUFC LycK+GgH20QFQZaz5ynYaFB1tXG8x6S9YJ70vS0qNze8zV/faDnm/DGP45Q7aX/4 cdakv24H6HAnF9nEHnq3tE4RGyoqm3v0YmT+bL3qUjObuQKw0e8k+7VRebImXZuT 2CKPUWVWmlgfpHJGpxVNYbqCQUDcMgXao= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; s=thelastpickle.com; bh=pI2MBlY3aewvTZVh oX/5KsDyUmY=; b=R0PPCSeq5TAciHE1r4eS4L/ZL+jPjWAFlhgXz+As9Qlsr+GP qYrfJBW33MEEE9Oi7rwVDZIcc/W0X9y1AYxr5YixfkMX24Yb1LDAGDmgwP/MedyE 55DkIqDUk8r/18Kqce/qPUF30x7DwvOnLC4LKBleiss5uxyna5dFMcfAQ8I= Received: from [172.16.1.4] (unknown [203.86.207.101]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a91.g.dreamhost.com (Postfix) with ESMTPSA id A5437AE075 for ; Thu, 7 Jun 2012 02:41:22 -0700 (PDT) From: aaron morton Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: multipart/alternative; boundary="Apple-Mail=_58EA130F-84F3-422B-B4D8-78BBF3520D27" Subject: Re: Secondary Indexes, Quorum and Cluster Availability Date: Thu, 7 Jun 2012 21:41:19 +1200 In-Reply-To: To: user@cassandra.apache.org References: Message-Id: X-Mailer: Apple Mail (2.1278) --Apple-Mail=_58EA130F-84F3-422B-B4D8-78BBF3520D27 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Sounds good. Do you want to make the change ?=20 Thanks for taking the time.=20 ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 7/06/2012, at 7:54 AM, Jim Ancona wrote: > On Tue, Jun 5, 2012 at 4:30 PM, Jim Ancona = wrote: > It might be a good idea for the documentation to reflect the tradeoffs = more clearly. >=20 > Here's a proposed addition to the Secondary Index FAQ at = http://wiki.apache.org/cassandra/SecondaryIndexes >=20 > Q: How does choice of Consistency Level affect cluster availability = when using secondary indexes? > A: Because secondary indexes are distributed, you must have CL level = nodes available for all token ranges in the cluster in order to complete = a query. For example, with RF =3D 3, when two out of three consecutive = nodes in the ring are unavailable, all secondary index queries at CL =3D = QUORUM will fail, however secondary index queries at CL =3D ONE will = succeed. This is true regardless of cluster size. >=20 > Comments? >=20 > Jim --Apple-Mail=_58EA130F-84F3-422B-B4D8-78BBF3520D27 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii
http://www.thelastpickle.com

On 7/06/2012, at 7:54 AM, Jim Ancona wrote:

On Tue, = Jun 5, 2012 at 4:30 PM, Jim Ancona <jim@anconafamily.com> wrote:
It might be a good idea for the documentation to reflect the tradeoffs = more clearly.

Here's a proposed addition to the = Secondary Index FAQ at http://wiki.apa= che.org/cassandra/SecondaryIndexes

Q: How does choice of Consistency = Level affect cluster availability when using secondary indexes?
A: = Because secondary indexes are distributed, you must have CL level nodes = available for all token ranges in the cluster in order to = complete a query. For example, with RF =3D 3, when two out of three = consecutive nodes in the ring are unavailable, all secondary = index queries at CL =3D QUORUM will fail, however secondary index = queries at CL =3D ONE will succeed. This is true regardless of cluster = size.

Comments?

Jim

= --Apple-Mail=_58EA130F-84F3-422B-B4D8-78BBF3520D27--