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 01B9210446 for ; Fri, 6 Dec 2013 15:54:40 +0000 (UTC) Received: (qmail 60638 invoked by uid 500); 6 Dec 2013 15:54:37 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 60622 invoked by uid 500); 6 Dec 2013 15:54:37 -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 60591 invoked by uid 99); 6 Dec 2013 15:54:37 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 06 Dec 2013 15:54:37 +0000 Date: Fri, 6 Dec 2013 15:54:37 +0000 (UTC) From: "Jonathan Ellis (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (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.atla= ssian.jira.plugin.system.issuetabpanels:all-tabpanel ] Jonathan Ellis updated CASSANDRA-6268: -------------------------------------- Fix Version/s: 2.0.4 1.2.13 > 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 > Fix For: 1.2.13, 2.0.4 > > Attachments: 6268-src-1.2.txt, 6268-src-2.0.txt, 6268-thrift-1.2.= txt, 6268-thrift-2.0.txt > > > 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. Splits ar= e generated from the results of describe_ring, which returns a huge number = of ranges anyways, and doesn't take into account that there will be huge nu= mber of consecutive ranges residing on the nodes we'd like the M/R job to b= e run. > The proposed fix: > 1. allows for specifying the DC(s) the Hadoop job should be run in (in DS= E - defaults to all Hadoop DCs) > 2. merges consecutive ranges before generating Hadoop splits, so we don't= have artificial range splitting caused by vnodes in the other DCs > For non-DSE users this feature is turned off by default and doesn't chang= e the old behaviour. -- This message was sent by Atlassian JIRA (v6.1#6144)