Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id BCD302009F8 for ; Fri, 3 Jun 2016 23:23:00 +0200 (CEST) Received: by cust-asf.ponee.io (Postfix) id BB795160A50; Fri, 3 Jun 2016 21:23:00 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 3EBFD160A3B for ; Fri, 3 Jun 2016 23:23:00 +0200 (CEST) Received: (qmail 38804 invoked by uid 500); 3 Jun 2016 21:22:59 -0000 Mailing-List: contact issues-help@drill.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@drill.apache.org Delivered-To: mailing list issues@drill.apache.org Received: (qmail 38786 invoked by uid 99); 3 Jun 2016 21:22:59 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 03 Jun 2016 21:22:59 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id 334762C1F5D for ; Fri, 3 Jun 2016 21:22:59 +0000 (UTC) Date: Fri, 3 Jun 2016 21:22:59 +0000 (UTC) From: "Jacques Nadeau (JIRA)" To: issues@drill.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (DRILL-4706) Fragment planning causes Drillbits to read remote chunks when local copies are available MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 archived-at: Fri, 03 Jun 2016 21:23:00 -0000 [ https://issues.apache.org/jira/browse/DRILL-4706?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15314839#comment-15314839 ] Jacques Nadeau commented on DRILL-4706: --------------------------------------- Drill tries to balance parallelism and distribution. The factor that influences this is called planner.affinity_factor. It doesn't guarantee locality but varying it will impact the balance. HDFS does not currently implement a required locality concept. > Fragment planning causes Drillbits to read remote chunks when local copies are available > ---------------------------------------------------------------------------------------- > > Key: DRILL-4706 > URL: https://issues.apache.org/jira/browse/DRILL-4706 > Project: Apache Drill > Issue Type: Bug > Components: Query Planning & Optimization > Affects Versions: 1.6.0 > Environment: CentOS, RHEL > Reporter: Kunal Khatua > Labels: performance, planning > > When a table (datasize=70GB) of 160 parquet files (each having a single rowgroup and fitting within one chunk) is available on a 10-node setup with replication=3 ; a pure data scan query causes about 2% of the data to be read remotely. > Even with the creation of metadata cache, the planner is selecting a sub-optimal plan of executing the SCAN fragments such that some of the data is served from a remote server. -- This message was sent by Atlassian JIRA (v6.3.4#6332)