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 D03ABD782 for ; Thu, 3 Jan 2013 13:32:41 +0000 (UTC) Received: (qmail 23237 invoked by uid 500); 3 Jan 2013 13:32:39 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 23220 invoked by uid 500); 3 Jan 2013 13:32:39 -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 23199 invoked by uid 99); 3 Jan 2013 13:32:38 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 03 Jan 2013 13:32:38 +0000 X-ASF-Spam-Status: No, hits=-2.3 required=5.0 tests=RCVD_IN_DNSWL_MED,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [192.174.58.134] (HELO XEDGEA.nrel.gov) (192.174.58.134) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 03 Jan 2013 13:32:32 +0000 Received: from XHUBA.nrel.gov (10.20.4.58) by XEDGEA.nrel.gov (192.174.58.134) with Microsoft SMTP Server (TLS) id 8.3.245.1; Thu, 3 Jan 2013 06:32:10 -0700 Received: from MAILBOX2.nrel.gov ([fe80::19a0:6c19:6421:12f]) by XHUBA.nrel.gov ([::1]) with mapi; Thu, 3 Jan 2013 06:32:11 -0700 From: "Hiller, Dean" To: "user@cassandra.apache.org" Date: Thu, 3 Jan 2013 06:32:11 -0700 Subject: Re: Multi threads updating single row Thread-Topic: Multi threads updating single row Thread-Index: Ac3ptruc8xpt7DxMQLKeKe8AghMYrA== Message-ID: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Microsoft-MacOutlook/14.2.5.121010 acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Virus-Checked: Checked by ClamAV on apache.org Multiple nodes could be a problem but multiple threads is probably just fin= e. If you have two threads write to the same column, the last one wins tho= ugh so I hope your timestamps are unique even across threads so you don't l= ose data ;). Dean From: Jay Svc > Reply-To: "user@cassandra.apache.org" > Date: Wednesday, January 2, 2013 4:55 PM To: "user@cassandra.apache.org" > Subject: Multi threads updating single row Happy New Year Everyone..! In the situation, there are multiple client thread updating or adding new c= olumns in a same row. These new columns is a time series data. My Question is - Would multiple threads able to add columns to the same row= ? Do you see any performance issues since there is a comparator and has to = sort columns as they get added. Do you see any loss of data or conflict due= to mulitple thread updating data? I am expecting high volumn of data comin= g on each one of those threads. Thanks in advance. Jay