Return-Path: X-Original-To: apmail-crunch-dev-archive@www.apache.org Delivered-To: apmail-crunch-dev-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 396651832B for ; Thu, 10 Dec 2015 06:43:12 +0000 (UTC) Received: (qmail 10660 invoked by uid 500); 10 Dec 2015 06:43:11 -0000 Delivered-To: apmail-crunch-dev-archive@crunch.apache.org Received: (qmail 10616 invoked by uid 500); 10 Dec 2015 06:43:11 -0000 Mailing-List: contact dev-help@crunch.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@crunch.apache.org Delivered-To: mailing list dev@crunch.apache.org Received: (qmail 10586 invoked by uid 500); 10 Dec 2015 06:43:11 -0000 Delivered-To: apmail-incubator-crunch-dev@incubator.apache.org Received: (qmail 10582 invoked by uid 99); 10 Dec 2015 06:43:11 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 10 Dec 2015 06:43:11 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id C9F392C14F7 for ; Thu, 10 Dec 2015 06:43:11 +0000 (UTC) Date: Thu, 10 Dec 2015 06:43:11 +0000 (UTC) From: "Jeffrey Quinn (JIRA)" To: crunch-dev@incubator.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (CRUNCH-580) FileTargetImpl#handleOutputs Inefficiency on S3NativeFileSystem MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CRUNCH-580?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15050186#comment-15050186 ] Jeffrey Quinn commented on CRUNCH-580: -------------------------------------- Thanks Josh! > FileTargetImpl#handleOutputs Inefficiency on S3NativeFileSystem > --------------------------------------------------------------- > > Key: CRUNCH-580 > URL: https://issues.apache.org/jira/browse/CRUNCH-580 > Project: Crunch > Issue Type: Bug > Components: Core, IO > Affects Versions: 0.13.0 > Environment: Amazon Elastic Map Reduce > Reporter: Jeffrey Quinn > Assignee: Josh Wills > Fix For: 0.14.0 > > Attachments: CRUNCH-580.patch, CRUNCH-580.patch > > > We have run in to a pretty frustrating inefficiency inside of org.apache.crunch.io.impl.FileTargetImpl#handleOutputs. > This method loops over all of the partial output files and moves them to their ultimate destination directories, calling org.apache.hadoop.fs.FileSystem#rename(org.apache.hadoop.fs.Path, org.apache.hadoop.fs.Path) on each partial output in a loop. > This is no problem when the org.apache.hadoop.fs.FileSystem in question is HDFS where #rename is a cheap operation, but when an implementation such as S3NativeFileSystem is used it is extremely inefficient, as each iteration through the loop makes a single blocking S3 API call, and this loop can be extremely long when there are many thousands of partial output files. -- This message was sent by Atlassian JIRA (v6.3.4#6332)