Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id C3637101B8 for ; Tue, 29 Oct 2013 19:53:25 +0000 (UTC) Received: (qmail 88030 invoked by uid 500); 29 Oct 2013 19:53:25 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 88009 invoked by uid 500); 29 Oct 2013 19:53:25 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 88000 invoked by uid 99); 29 Oct 2013 19:53:25 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 29 Oct 2013 19:53:25 +0000 Date: Tue, 29 Oct 2013 19:53:25 +0000 (UTC) From: "Jonathan Ellis (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CASSANDRA-6268) Poor performance of Hadoop if any DC is using VNodes MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-6268?page=3Dcom.atlas= sian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=3D= 13808368#comment-13808368 ]=20 Jonathan Ellis commented on CASSANDRA-6268: ------------------------------------------- We closed CASSANDRA-6124 in favor of adding LOCAL_ONE; I can't think of a c= ase where you'd want to span more than one DC but less than all. > Poor performance of Hadoop if any DC is using VNodes > ---------------------------------------------------- > > Key: CASSANDRA-6268 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6268 > Project: Cassandra > Issue Type: Improvement > Components: Hadoop > Reporter: Piotr Ko=C5=82aczkowski > Assignee: Piotr Ko=C5=82aczkowski > Attachments: 0001-DSP-2572-Adds-ability-to-set-target-DCs-where-a= -Hado.patch > > > Some customers are complaining about huge number of splits in Hadoop caus= ed by VNodes. Disabling vnodes only in Hadoop DC does not fix it, because s= plits are generated from the results of describe_ring, which returns a huge= number of ranges.=20 > The proposed fix: > - allows for specifying the DCs the Hadoop job should be run > - merges the consecutive ranges before generating Hadoop splits, so we do= n't have artificial range splitting caused by vnodes in the other DCs -- This message was sent by Atlassian JIRA (v6.1#6144)