Return-Path: X-Original-To: apmail-spark-issues-archive@minotaur.apache.org Delivered-To: apmail-spark-issues-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id B3097173C6 for ; Fri, 7 Nov 2014 02:05:35 +0000 (UTC) Received: (qmail 22730 invoked by uid 500); 7 Nov 2014 02:05:35 -0000 Delivered-To: apmail-spark-issues-archive@spark.apache.org Received: (qmail 22548 invoked by uid 500); 7 Nov 2014 02:05:35 -0000 Mailing-List: contact issues-help@spark.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Delivered-To: mailing list issues@spark.apache.org Received: (qmail 22413 invoked by uid 99); 7 Nov 2014 02:05:35 -0000 Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 07 Nov 2014 02:05:35 +0000 Date: Fri, 7 Nov 2014 02:05:35 +0000 (UTC) From: "Aaron Davidson (JIRA)" To: issues@spark.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Commented] (SPARK-2468) Netty-based block server / client module 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/SPARK-2468?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14201432#comment-14201432 ] Aaron Davidson commented on SPARK-2468: --------------------------------------- [~zzcclp] I believe it is close to merging. [~rxin] is finishing up his review. > Netty-based block server / client module > ---------------------------------------- > > Key: SPARK-2468 > URL: https://issues.apache.org/jira/browse/SPARK-2468 > Project: Spark > Issue Type: Improvement > Components: Shuffle, Spark Core > Reporter: Reynold Xin > Assignee: Reynold Xin > Priority: Critical > Fix For: 1.2.0 > > > Right now shuffle send goes through the block manager. This is inefficient because it requires loading a block from disk into a kernel buffer, then into a user space buffer, and then back to a kernel send buffer before it reaches the NIC. It does multiple copies of the data and context switching between kernel/user. It also creates unnecessary buffer in the JVM that increases GC > Instead, we should use FileChannel.transferTo, which handles this in the kernel space with zero-copy. See http://www.ibm.com/developerworks/library/j-zerocopy/ > One potential solution is to use Netty. Spark already has a Netty based network module implemented (org.apache.spark.network.netty). However, it lacks some functionality and is turned off by default. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org For additional commands, e-mail: issues-help@spark.apache.org